What are the major principles of the cell theory? 1. All living things are made up of one or more cells; 2.Cells are the...
What are three common features that all cells share? 1. A boundary that separates the internal environment of the cell...
Distinguish between prokaryotes and eukaryotes. Eukaryotes have a membrane nucleus, and often other membrane bound...
Why are cells so small? Volume determines amount of chemical activities a cell can carry out . Surface area determines...
What are the major principles of the cell theory
What are three common features that all cells share
exchange across cell membrane.
Why are images more detailed in an electron microscope than in a light microscope? An electron microscope uses a beam of electrons, rather than electromagnetic radiation, to "illuminate the specimen."
Who were Antone van Leeuwenhoek and Rudolf Virchow? Leeuwenhoek was an expert at making lenses, improved the microscope. First person to see bacteria. Virchow studied diseased cells, tumor growth, the healing of wounds, and the development of...
Why are cells so small
Volume determines amount of chemical activities a cell can carry out
development of cell theory.
How does DNA differ in prokaryotes and eukaryotes? DNA in prokaryotes is found in a singular, circular loop (nucleiod) which floats freely in the cell. In the...
What are pili? Pili are threadlike structures, shorter than flagella, which project from the surfaces of some bacteria. The pili help bacteria to adhere to one...
What are the major organelles in eukaryotic cells? Organelles are important because they separate biochemical reactions from one another. Important organelles...
Why are images more detailed in an electron microscope than in a light microscope
An electron microscope uses a beam of electrons, rather than electromagnetic radiation, to "illuminate the specimen." .
Who were Antone van Leeuwenhoek and Rudolf Virchow
Leeuwenhoek was an expert at making lenses, improved the microscope
will be exported out of the cell or to other organelles.
What is the function of the Golgi apparatus (complex). Biomolecules - protein, lipids and...
Distinguish between rough and smooth ER. Rough ER. The folded membrane of the Rough ER forms...
What are ribosomes? Where are they synthesized? Ribosome synthesis begins within the nucleus,...
What two organelles in eukaryotes have their own DNA? Both the chloroplast and the mitochondria...
Distinguish between cancer cells and normal cells. Decreased density dependent growth...
How does DNA differ in prokaryotes and eukaryotes
DNA in prokaryotes is found in a singular, circular loop (nucleiod) which floats freely in the cell
What are pili
Pili are threadlike structures, shorter than flagella, which project from the surfaces of some bacteria
What are the major organelles in eukaryotic cells
Organelles are important because they separate biochemical reactions from one another
Important organelles include
Nucleus-contains the chromosomes (DNA)
membrane structures in cells, continuous with the nuclear membrane, entrance to the cell secretory system
dotted with ribosomes; proteins are synthesized on ribosomes of the rough ER
lipids and carbohydrate synthesis
packaging site for biomolecules that
unstable and often express gross chromosomal abnormalities
What are stem cells? Where do they come from? Cell with the potential for self renewal and the capacity to generate more specialized cells. SCs at different developmental stages appear to have different capacities for self-renewal and differentiation
Can a cell?s function be predicted by the types of organelles it has? Yes, often times function correlates with structure.
What two organelles in eukaryotes have their own DNA
Both the chloroplast and the mitochondria have their own DNA
Organelle membranes have the following functions: To separate substances from on another. Some membrane organelles help transform energy [mitochondrial membrane, thykaloid membrane]. Some membranes organize chemical reactions. Some membrane proteins process information.
What is meant by membrane fluidity? This means that some molecules can move laterally within the plane of the membrane.
What features of the fatty acid tails in the phospholipid bilayer control membrane fluidity? The fluidity of a membrane varies according to its lipid composition...
Distinguish between integral and peripheral membrane proteins. Integral membrane protein have hydrophobic domains and penetrate the phospholipid bilayer....
Can a cell’s function be predicted by the types of organelles it has
Yes, often times function correlates with structure
polar regions that interact with polar regions of integral membrane proteins or with polar heads of phospholipid molecules.
What are the functions of membrane carbohydrates? Distinguish between glycolipids and glycoproteins. Membrane carbohydrates are recognition sites for cells and...
Distinguish between diffusion and osmosis. Diffusion is the process of random movement towards a state of equilibrium. The net movement of particles from regions...
What factors control diffusion across the cell membrane? 1. The size (diameter) of the molecules or ion: smaller molecules defuse faster. The temperature of the...
diffusing material. The concentration gradient of the system, (the change of solute concentration in a given direction.)
Why can?t polar molecules readily diffuse across the cell membrane? The interior of the membrane, comprised of fatty acid acid tails, is nonpolar. Polar molecules tend to be excluded from nonpolar areas, and also tend to bond with polar water molecules, which prevents them from passing easily through the
membrane. However, while most polar molecules cannot pass through easily, some smaller polar molecules can pass through easily (water).
How do diffusion and facilitated diffusion differ? Diffusion refers to the random movement of particles towards a state of equilibrium. Osmosis is an example of this. Facilitated diffusion occurs when polar ions pass through the bilayer passively, either by passing through integral membrane protein channels or by
binding with a carrier protein in the membrane. When a stimulus molecule binds with a channel protein, it changes its three dimensional shape, allowing certain ions to pass through.
What is active transport? One hallmark of living things is that they can have a composition quite different from that of their environment. This requires more than passive diffusion; it requires the cell to expend energy. In order to move a substance against a concentration gradient, chemical energy must be
expended. This process is called active transport.
Distinguish between exocytosis and endocytosis. How does pinocytosis differ from phagocytosis? Endocytosis is a process of bringing large molecules into the cell, exocytosis is a process of releasing large molecules into the extracellular. Phagocytosis occurs when part of the plasma membrane engulfs a large particle or even an entire cell. The food vacuole that engulfs this molecule or cell usually fuses with a lysosome, and digestion occurs. In pinocytosis, part... (character limit exceeded)
What are tight junctions? Tight junctions are specialized structures that link adjacent epithelial cells [epithelium--tissue composed of cells that line cavities and surfaces throughout the body]. Prevent substances from moving through the spaces between cells; therefore, substances entering the body must
In the cell membrane why do the phosphate heads point outward and inward in the phospholipid bilayer
The phosphate head point towards aqueous environments (outward towards the extracellular environment and inward toward the interior of the cell) because these heads are hydrophilic (polar), and thus are attracted to H20, which is also polar
What are the functions of the cell membrane
It allows certain substances to enter the cell, while preventing others from doing so (selective permeability)
What is meant by membrane fluidity
This means that some molecules can move laterally within the plane of the membrane
What features of the fatty acid tails in the phospholipid bilayer control membrane fluidity
The fluidity of a membrane varies according to its lipid composition and temperature
What are the functions of membrane carbohydrates
Distinguish between glycolipids and glycoproteins
What factors control diffusion across the cell membrane
Why can’t polar molecules readily diffuse across the cell membrane
The interior of the membrane, comprised of fatty acid acid tails, is nonpolar
How do diffusion and facilitated diffusion differ
Diffusion refers to the random movement of particles towards a state of equilibrium
synthesizing components of microtubules that will be used to move the chromatids to opposite of the dividing cell, for example. Finally, during M phase the cell undergoes division into two daughter cells that each contain the same genetic information.
What is G0? A resting phase. Cells that enter this state do not go through the cell cycle, until special internal and external signals prompt the cell to re-enter the cell cycle.
Where are the checkpoints located in the cell cycle? What is the purpose of check points? Checkpoints are points at which the progress of the cell cycle can be monitored to determine whether the cell should move to the next step or not. For example, if DNA is
What is active transport
One hallmark of living things is that they can have a composition quite different from that of their environment
the rest of the cell cycle is normally inevitable, during the S phase, to stimulate DNA replication, and at the G2-M boundary, initiating the beginning of mitosis.
What is the function of kinase? Kinase is an enzyme that catalyzes the transfer of a phosphate group from ATP to another molecule (phosphorylation). This process changes the shape and the function of the protein by changing its electrical charges.
Where do Cyclins D and E function in the cell cycle? What is the role of cyclindependent kinase (Cdk) in the cell cycle? Cyclins D and E function to move the cell past its restriction point, after which the rest of the cell cycle is normally...
How does pinocytosis differ from phagocytosis
Endocytosis is a process of bringing large molecules into the cell, exocytosis is a process of releasing large molecules into the extracellular
enzyme that catalyzes the transfer of a phosphate group from ATP to another molecule, changing the shape and function of the protein by changing its electrical charge. When Cdks bind with cyclin, another protein, it changes shape, and it catalyzes transitions in the cell cycle.
Is phosphorylated retinoblastoma protein functional? Why or why not? No. Retinoblastoma...
What are the phases of mitosis? What are the distinguishing features of each phase? Interphase...
What are chromatids? How many chromatids does a homologous pair of chromosomes have? Chromatids...
What are homologous chromosomes? Chromosomes that bare corresponding, although generally not...
Distinguish between mitosis and meiosis. Mitosis occurs in somatic cells, and results in two...
What are tight junctions
Tight junctions are specialized structures that link adjacent epithelial cells [epithelium--tissue composed of cells that line cavities and surfaces throughout the body]
meiosis include: reducing the chromosome number from diploid to haploid, ensuring that each haploid product has a complete set of chromosomes, and promoting genetic diversity in its products.
Distinguish between anaphase I and anaphase II of meiosis. In Anaphase I, two homoogous...
If a particular cell has 24 chromosomes in G1 how many chromosomes will the cell have in G2?...
What is the role of the centrosome in cell division? The centrosome determines the plane of...
What is the role of the centromere in mitosis? The centromere holds the sister chromatids...
When do chromatids separate in mitosis? When do chromatids separate in meiosis? The chromatids...
Guanine, Cytosine, or Thymine).
What are the four major structural features of DNA? 1. It is a double-stranded helix of uniform diameter. 2. It is right-handed. (curvature is counter-clockwise) 3. It is antiparallel. (the two strands run in opposite directions) 4. The outer edges of the nitrogenous
What is G0
A resting phase
bases are exposed in the major and minor grooves.
The two strands of a DNA molecule are anti-parallel. What does that mean? In a DNA double-helix, the 5' end of one...
What is the difference between the 3? and 5? end of a DNA molecule? The 5' end of the of the polynucleotide chain...
What is Chargaff?s rule? The total number of purines (A and G) is equal to the total number of Pyrimdines (T and C)....
What is the difference between conservative, semi-conservative and dispersive replication of DNA? Semiconservative...
What is the function of kinase
Kinase is an enzyme that catalyzes the transfer of a phosphate group from ATP to another molecule (phosphorylation)
containing old and new parts, perhaps at random.
Describe Watson and Crick?s contribution to our current understanding of DNA? Watson and Crick were the first to model the general structure of DNA.
In what direction does DNA replication occur? DNA replicates in both directions from the origin of replication, forming two replication forks. DNA Polymerase...
What is a replication fork? What is the role of DNA polymerase? A replication fork forms when DNA replicates in both directions from the origin of replication...
DNA polymerase elongates both strands, adding nucleotides to the free 3' end.
A DNA template strand has the following base sequence: 5?-ATGGCTTAT-3?.What is the base sequence of the newly synthesized complementary strand? 3' TACCGAATA -5'
What is excision repair of DNA damage? Give an example of a human disease in which excision repair is defective. Excision repair is a mechanism that removes...
Distinguish between point mutations and chromosomal aberrations. Point mutations (silent, missense, nonsense, or frame-shift) result from alterations in single...
What are homologous chromosomes
Chromosomes that bare corresponding, although generally not identical, genetic material
reducing the chromosome number from diploid to haploid, ensuring that each haploid product has a complete set of chromosomes, and promoting genetic diversity in its products
If a particular cell has 24 chromosomes in G1 how many chromosomes will the cell have in G2
The cell will have 48 paired sister chromatids by G2
What is the role of the centrosome in cell division
The centrosome determines the plane of cell division
What is the role of the centromere in mitosis
The centromere holds the sister chromatids together, up until anaphase, when it is dissolved
What are the three major components of the DNA molecule
The DNA molecule is helical, which means that it is a cylindrical spiral
sequence of a polypeptide.
What are the differences between DNA and RNA? RNA is the key intermediary between DNA and polypeptide. It differs from DNA in three important ways: 1. RNA generally consists of only one polynucleotide strand. 2. The sugar molecule found in
What are the four major structural features of DNA
RNA is ribose, rather than the deoxyribose found in DNA. 3. RNA has uracil (U) rather than thymine (T).
A segment of DNA contains the following sequence: 3?-TACTGTGGAATT-5?. What is the mRNA transcript? The base sequence of the DNA strand that is transcribe is complementary and anti-parallel to the mRNA product. Therefore: 5'-
AUGACACCUUAA - 3
Describe the three stages of transcription. 1. Initiation. Requires a promoter, a special sequence of DNA to which RNA polymerase binds very tightly. Promoters provide information to the RNA polymerase as to where to start transcription, which strand of
What does that mean
In a DNA double-helix, the 5' end of one strand is paired with the 3' end of the other, and vice versa
What is the difference between the 3’ and 5’ end of a DNA molecule
The 5' end of the of the polynucleotide chain contains a free 5' phosphate group, while the 3' end contains a free 3' hydroxl group
Termination. Just as specific base pairs specify the starting point for transcription, particular bases specify its termination. There are a number of mechanisms of termination: in some cases, the newly formed transcript falls away, while in others, a helper protein pulls the transcript away.
After transcription how is the newly synthesized mRNA modified? Enzymes modify pre-mRNA before the genetic messages are dispatched to the cytoplasm. At the 5? end of the pre-mRNA molecule, a modified form of guanine is added, the 5? cap. This helps
What is Chargaff’s rule
The total number of purines (A and G) is equal to the total number of Pyrimdines (T and C)
What is the difference between conservative, semi-conservative and dispersive replication of DNA
Semiconservative replication (correct) - each parent strand serves as a template for a new strand, and the two new DNA molecules each have one old and one
also seems to facilitate the export of mRNA from the nucleus. The mRNA molecule also includes nontranslated leader and trailer segments.
What is the function of the spliceosome? Responsible for RNA splicing, the removal of a large portion of the RNA molecule. Most eukaryotic genes and their RNA transcripts have long noncoding stretches of nucleotides (introns). The final mRNA transcript
includes exons that are translated into amino acid sequences, plus the leader and trailer sequences. Spliceosomes consist of a variety of proteins and several small nuclear ribonucleoproteins (snRNPs).
Distinguish among messenger RNA (mRNA), ribosomal RNA (rRNA) and transfer RNA (tRNA). mRNA forms as a complementary copy of one DNA strand of a particular gene, then it travels from the nucleus to the cytoplasm, where it serves as a template for
Describe Watson and Crick’s contribution to our current understanding of DNA
Watson and Crick were the first to model the general structure of DNA
the synthesis of proteins at the ribosomes. tRNA is an an adapter molecule that can both bind a specific amino acid and recognize a sequence of nucleotides. tRNAs translate the language of DNA into the language of proteins. tRNAs line up on the mRNA sequence so that the amino acids are in the proper sequence for a growing polypetide chain, a process called translation. The tRNA molecule carries (is charged with) an amino acid, associates with mRNA molecules, and... (character limit exceeded)
What happens at the A site, P site and E site of the ribosome during translation? Each ribosome has a binding site for mRNA and three binding sites for tRNA...
What is post-translational modification of protein? Modifications of a protein that occur after translation has been completed. Three types. Proteolysis: Cutting...
What is the function of the promoter sequence in DNA? The presence of a promoter sequence determines which strand of the DNA helix is the template. Within the...
In what direction does DNA replication occur
DNA replicates in both directions from the origin of replication, forming two replication forks
What is excision repair of DNA damage
Give an example of a human disease in which excision repair is defective
(ethanol), which are still relatively energy-rich molecules. Because the breakdown of glucose is incomplete, much less energy is released by fermentation than by cellular respiration.
How does the cell store energy? Primarily in ATP. Energy is released when a phosphate bond is broken to form ADP.
The starting product in glycolysis is glucose. What is (are) the end product(s)? Two molecules of the the three-carbon...
Which metabolic processes do not require oxygen? Anaerobic processes do not require oxygen. Fermentation is an anaerobic...
Distinguish among electron carrier, oxidizing agent and reducing agent. The oxidizing agent is the atom, ion, or...
more electrons in a redox reaction (electron donor). Note that an agent need not only gain or lose electrons; it can gain or lose an entire hydrogen atom. Reduction reactions require an input of energy. Oxidizing reactions release energy. An electron carrier is a molecule that can accept and donate electrons from and to various enzymes; that is, it can be either a reducing or oxidizing agent. An example is the coenzyme NAD, which exists in an oxidized form (NAD+)... (character limit exceeded)
What are the major electron carriers in cellular respiration? NAD and FAD.
Can oxidation occur in the absence of reduction? Explain. No. Oxidation and reduction always occur together: as one...
What metabolic processes are carried out in mitochondria? All processes included in cellular respiration. The cytric...
Briefly describe how ATP is made from ADP using the ATP synthase process? In the electron transport chain, protons are...
movement to the synthesis of ATP, in a process called chemiosmosis. ATP synthase uses the energy of the proton diffusion to make ATP from ADP and a free phosphate atom.
What is the role of oxygen in the electron transport chain? Oxygen accepts...
Which stage of cellular respiration consumes ATP? 2 ATP are consumed in the...
How can fats and proteins be used as fuel in cellular respiration? ? Fats are...
Why are there fewer ATP/glucose produced in fermentation than in cellular...
Why is glucose metabolized in multiple steps? Were it metabolized in a single...
Do energy transformations occur during metabolic breakdown of glucose?...
What is the central dogma of molecular biology
DNA codes for the production of RNA, RNA codes for the production of proteins (polypeptide), and protein does not code for the production of protein, RNA, or DNA
What are the differences between DNA and RNA
RNA is the key intermediary between DNA and polypeptide
What is the mRNA transcript
The base sequence of the DNA strand that is transcribe is complementary and anti-parallel to the mRNA product
After transcription how is the newly synthesized mRNA modified
Enzymes modify pre-mRNA before the genetic messages are dispatched to the cytoplasm
What is the function of the spliceosome
Responsible for RNA splicing, the removal of a large portion of the RNA molecule
occur on the thylakoid membrane. Dark reactions occur in the stroma. The two pathways are linked by the exchange of ATP and ADP and of NADP+ and NADPH, and the rate of each set of reactions depends on the other.
What are the major reactants in photosynthesis? What are the major products?...
Why are photosynthesizing organisms (e.g. plants) green? Because chlorophyll...
What is a reaction center? The molecule in the antenna system that converts...
What colors of light are preferentially absorbed by chlorophyll? Red and blue.
What is the source of oxygen as a waste product of photosynthesis? Water.
What happens to an electron if it goes through photosystem I? If in noncyclic...
A gene is transcribed to produce a messenger RNA molecule complementary to one of the DNA strands
10.What happens at the A site, P site and E site of the ribosome during translation
Each ribosome has a binding site for mRNA and three binding sites for tRNA molecules.
11.What is post-translational modification of protein
Modifications of a protein that occur after translation has been completed.
photosystem II will eventually join the chlorophyll in photosystem.
What are the three major events in the Calvin-Benson cycle? The fixation of CO2. Catalyzed by the enzyme rubisco; produces 3PG. Reduction of 3PG to form glyceraldehyde 3-phosphate (G3P). This series of reactions involves a phosphorylation
Cutting the protein to allow fragments to fold into the proper shapes
Adding sugar groups which aid in targeting of proteins
Alter the shape of the protein
(using ATP made in the light reactions) and a reduction (using the NADPH made in the light reactions.) Regeneration of the CO2 acceptor, RuBP. Most of the G3P ends up as RuMP, and ATP is used to convert this compound into RUBP.
Distinguish between cyclic and non-cyclic electron flow in the light reaction? What products are produced in each pathway? Cyclic electron transport produces ATP but not NADPH. Electron passed from an excited P700 (pigment) molecule cycles back to the
What is the function of the promoter sequence in DNA
The presence of a promoter sequence determines which strand of the DNA helix is the template
same P 700 molecule. Cyclic electron transport only involves Photosystem 1. Non-cyclic electron flow produces both ADP and NADPH+H+.
How is CO2 fixed in the Calvin-Benson cycle? The initial reaction of the Calvin Benson cycle fixes one CO2 to a 5-carbon compound RUBP using RUBP carboxylase (rubisco). An intermediate 6-carbon compound is unstable and breaks down to form two
3-carbon molecules of 3PG.
What is the end product of the Calvin-Benson cycle? What happens to it? G3P. 5/6 of the G3P is recycled into RuBP. Of the remaining G3P, 1/3 ends up in polysaccharide starch, which is stored in the chloroplast. 2/3 is converted into the disaccharide sucrose, which is transported out of the leaf to other organs in the plant.
Do energy transformations occur during photosynthesis? Yes. Light energy is converted into chemical energy.
What are the major metabolic processes used to breakdown glucose
Glycolysis, cellular respiration, and fermentation
How does the cell store energy
Primarily in ATP
What is (are) the end product(s)
Two molecules of the the three-carbon product pyruvate
Which metabolic processes do not require oxygen
Anaerobic processes do not require oxygen
? But, multicellularity imposes no new types of signaling requirements on cells
Distinguish among autocrine, paracrine and hormonal signals.
What are the major electron carriers in cellular respiration
NAD and FAD
Can oxidation occur in the absence of reduction
? Paracrinesignals diffuse to and affect nearby cells.
Hormones are signals to distant cells; usually travel through the circulatory system.
What is a signal transduction pathway? A signal transduction pathway involves the interaction of a signal molecule with a receptor; the transduction of the...
Distinguish between ligands with plasma bound receptors and ligands with cytoplasmic receptors. Distinguish signal molecules for each type of receptor. Ligands...
What metabolic processes are carried out in mitochondria
All processes included in cellular respiration
Briefly describe how ATP is made from ADP using the ATP synthase process
In the electron transport chain, protons are transported against their concentration gradient, across the inner membrane of the mitochondrion into the intermembrane space
membrane, such as steroids. Ligands with plasma membrane receptors: large and/or polar molecules that can not cross, such as insulin. Receptors are usually transmembraneproteins.
How does direct transduction differ from indirect transduction? Direct transduction occurs as a function of the binding of the receptor and the ligand. Occurs at the plasma membrane. Indirect transduction is transduction that involves second...
Give an example of a second messenger. How does it work? Cyclic AMP is a common and widely used second messenger. The effector enzyme that catalyzes the formation of cAMP is located on the the cytoplasmic surface of the plasma membrane of the...
What is the role of oxygen in the electron transport chain
Oxygen accepts electrons and hydrogen
as a result. This results in a protein kinase cascade, leading to final effects on the cell. In contrast to the specificity of receptor biding, second messengers affect many processes in the cell,and allow a cell to respond to a single event at the plasma membrane with many events inside the cell.
Briefly describe the biochemical defect in cystic fibrosis. CF is due to mutation in cystic fibrosis transmembraneconductancegene (CFTR)-chloride transporter protein
How does ViagraŽ work? ? Nitroglycerin is used to relax blood vessels in the heart to increase blood flow. Nitroglycerin increases NO levels in cells, NO (nitric oxide) acts as a second messenger causing an increase in cGMP and ensuing relaxation of the smooth
Which stage of cellular respiration consumes ATP
2 ATP are consumed in the beginning of glycolysis
How can fats and proteins be used as fuel in cellular respiration
• Fats are broken down into fatty acids and glycerol by digestion ? fatty acids are oxidized in mitochondria by process of ?-oxidation that converts fatty acids to acetyl-CoA which enters citric acid cycle
muscles in the corpus cavernosum of the penis, which fills with blood, resulting in an erection.
What general effects do signals have on cell function? Signals can cause ion channels to open. Signals can inhibit or activate enzymes. Signals can initiate gene transcription.
How do membrane receptors facilitate communication with a cell?s environment
Why are there fewer ATP/glucose produced in fermentation than in cellular respiration
Oxygen is not present to accept electrons in fermentation, so the net energy yield is low
Why is glucose metabolized in multiple steps
Were it metabolized in a single step, there would be no biochemical way to harvest the burst of energy
Do energy transformations occur during metabolic breakdown of glucose
Metabolic pathways are chemical transformations that occur in separate reactions
Energy exchange between the organism and the environment often involves
Metabolism involves a step-wise breakdown of energy sources (e.g.
Where do they occur in the chloroplast
The light reactions are driven by light energy
Because chlorophyll absorbs both blue and red light, but does not absorb green light
What is a reaction center
The molecule in the antenna system that converts the absorbed light energy into chemical energy
? There are two types of cells in nervous tissues: Neurons generate and transmit electrochemical signals, and glial cells provide supporting functions for neurons.
What is meant by epithelial polarity? Give an example of polarity. Epithelial cells display polarity(distinct inner and outer surfaces), which differ in both structure and function. Apical surfaces face either the environment or the lumen. These...
What are the major subtypes of: epithelial cells: differentiated by shape of cells. Simple cuboidal, stratified columnar,
What colors of light are preferentially absorbed by chlorophyll
Red and blue
What is the source of oxygen as a waste product of photosynthesis
What happens to an electron if it goes through photosystem I
If in noncyclic electron transport, the electron will be eventually reduce NADP+
simple squamous, stratified squamous, simple columnar. muscle cells: skeletal muscle, (moves the skeleton, striated) cardiac muscle (pumps blood, striated), smooth muscle (gut, urinary tract, and blood vessels, not striated) connective tissue: adipose tissue, tendons and ligaments, connective tissue, bone, cartilage, blood nerve cells: neurons and glial cells
Distinguish among tissue, organ and organ systems. A tissue is a group of cells that perform a specific function. Organs consist of two or more tissue types (often every type) ? Organs perform specific physiological functions ? Organ systems are groups of organs
The electron in
interconnected to perform one or more function
Describe the major organ systems (including tissues and organs) and what their functions are? (See table 40.1, in lecture outline)
Give two examples of how cell structure in a tissue supports the tissue function. The stomach is: lined by a secretorygastric epithelium which produces HCl, mucous, and proteases to degrade ingested proteins supported by connective tissue ringed by smooth
What are the three major events in the Calvin-Benson cycle
The fixation of CO2
How is CO2 fixed in the Calvin-Benson cycle
The initial reaction of the Calvin Benson cycle fixes one CO2 to a 5-carbon compound RUBP using RUBP carboxylase (rubisco)
physiological parameters (blood pressure, etc.) out to remain constant. If there is deviation from expected value, this indicates some pathology.
What is the extracellular fluid compartment? The extracellular fluid compartment is comprised of areas outside of cells that contain fluid. The extracellular fluid is 80% interstitial fluid, water trapped between cells in tissues, outside of the cardiovascular
Do energy transformations occur during photosynthesis
system. It is from this fluid that cells receive nutrients and into which they excrete wastes. 20% of the EFC is blood plasma, part of the cardiovascular system.
Distinguish among diffusion, facilitated diffusion, osmosis and active transport? Diffusion is the process of random movement towards a state of equilibrium. The net movement of particles from regions of greater concentration to regions of lesser
certain ions to pass through. Active transport involves the expenditure of chemical energy to move a substance against its concentration gradient.
Distinguish between a steady-state and equilibrium condition. A steady-state condition is regulated and requires the expenditure of energy. An equilibrium condition is not regulated and does not require the expenditure of energy. An example of an equilibrium
condition. In a steady-state condition: the nutrients consumed by cellular activity must be replaced from the external environment The waste products delivered to the internal environment must be dumped into the external environment. Constancy of the internal environment is dependent on an energy-dependent exchange of materials between the internal and external environments.
Vanessa weighs 50 kg. What is her total intracellular fluid weight? In human beings, 66% of the body's water is found in the intracellular fluid, while 33% is found in the extracellular fluid . Roughly 60% of a human's body weight is water. Therefore, the total
percentage of Vanessa's intracellular fluid is (ROUGHLY): (.60)(.66) = 40%
Distinguish between negative and positive feedback control. Give an example of each. Negative feedback: Reduces deviations in a regulatory system. Minimize changes. Regulatory system seeks to reduce the margin of error between the actual state and the set
? Feed forward information changes the set point
Compartment A (50 ml) and compartment B (500 ml) are separated by a permeable membrane. Each compartment is filled to its capacity with water and contains 1000 molecules of a solute. In which direction will net diffusion of the solute occur? At
compartment has the same amount of water. So, at equilibrium, the concentration of solute to water in each compartment will be: (1000/275) = 3.64 solute molecules/ml.
What is Fick?s law? Describe the major factors that control net diffusion. Jnet = Influx -Efflux = - DA([Co-Ci] /x). D is a diffusion coefficient, and varies from substance to substance. A is the cross-sectional area through which the substance is
What is a signal transduction pathway
A signal transduction pathway involves the interaction of a signal molecule with a receptor; the transduction of the signal via a responder within the cell; and an effect on the function of the cell
diffusing. Co is the pressure in the location where efflux that is occurring, while Ci is the pressure in the location where the influx is occurring. X is the distance between the two locations. Fick's law constrains certain features of plant and animal design ? For those physiological processes driven by diffusion, the efficiency of the process (as assessed by a higher flux rate) may be increased by: Maintenance of diffusion gradients (which normally tend to run... (character limit exceeded)
Distinguish between antiports, symports and uniports. Give an example of each. Antiport - a membrane protein that moves two substances in opposite directions, one into the cell and one out of the cell. Classical example, sodium-potassium pump....
How do negative and positive feedback loops contribute to homeostasis? In the case of negative feedback systems counteracts the original change in the variable being controlled. Positive feedback results in the amplification of a weak stimulus.
How does direct transduction differ from indirect transduction
Direct transduction occurs as a function of the binding of the receptor and the ligand
How does it work
Cyclic AMP is a common and widely used second messenger
surface of a body passageway that leads to the outside of the body.
How do hormones affect cells? What is meant by a ?target? cell? Hormones bind to receptors on target cells, and this binding triggers an intraceullular reaction that changes cell function. Polar hormones bind to membrane receptors, while nonpolar hormones
activity), moving active transporters from the plasma membrane where they are no longer effective, or stimulating the rate of excretion of other hormones (trophic hormones).
Distinguish between fat-soluble and water-soluble hormones? Peptide (protein) hormones, like insulin, and most amino acid derived hormones are water soluble. Steroid hormones and thyroid hormones are fat soluble.
Where are the parathyroid glands located? On the surface of the thyroid glands (in the neck). They produce parathyroid hormone, which elevates blood calcium levels.
Where are steroid hormones produced? Steroids are produced in the adrenal cortex, as
How does Viagra® work
• Nitroglycerin is used to relax blood vessels in the heart to increase blood flow
What general effects do signals have on cell function
Signals can cause ion channels to open
well as in the ovaries or testes.
Which endocrine gland stores but does not produce hormones? The posterior pituitary gland stores hormones produced in...
Which endocrine gland is associated with the flight or fight response? the adrenal gland, just above the kidney,...
What is the function of thyroxine? Which endocrine gland produces it? Thyroxine is produced in structures called...
What hormones play a role in calcium homeostasis? Calcitonin reduces blood calcium. It does this by decreasing the...
decrease in bone calcium and a net increase in blood calcium. PTH also stimulates the kidneys to reabsorb calcium rather than excrete it, and activates vitamin D, which in turn causes the digestive tract to enhance absorption of dietary calcium.
Which tropic hormones are secreted by the anterior pituitary? Where else are tropic hormones produced? The anterior pituitary produces the following tropic hormones: thyroid stimulating hormone, follicle stimulating hormone, luteinizing hormone, and
the endocrine system. Tropic hormones are not produced anywhere else in the body.
What are some common features of steroid hormones? Steroid hormones such as testosterone and estrogen are derivatives of the steroid cholesterol. They are lipid-soluble and easily dissolve in and pass through cell membranes. Diffuse out of cells that make
them as they are synthesized. Must be bound to carrier proteins in order to be transported to target cells, because they are not soluble in blood.
What is meant by up- or down-regulation of hormone receptors? Down-regulation occurs when continuous high levels of a hormone can decrease the number of its receptors. Up-regulation occurs when the levels of hormone secretion are suppressed, and
results in an increase in the number of receptors. Sensitivity and time course of hormone response depend on many factors, including receptor numbers, properties of signal transduction pathways, other hormones, binding of the hormone to carrier proteins, and elimination of the hormone through degradation and excretion.
Why are some receptors located in the interior of cells? Receptors for water-soluble hormones are on the cell surface, and receptors for lipid-soluble hormones are inside the cell, because lipid-soluble hormones can diffuse through the phospholipid bilayer.
How does the structure of endocrine glands facilitate their function? Endocrine glands are richly vascularized (have many blood vessels), which is essential to their mode of secretion.
What is meant by epithelial polarity
Give an example of polarity
Describe the major organ systems (including tissues and organs) and what their functions are
(See table 40.1, in lecture outline) .
The stomach is
lined by a secretorygastric epithelium which produces HCl, mucous, and proteases to degrade ingested proteins supported by connective tissue ringed by smooth
with a target cell
What is meant by resting potential? What is an action potential? Membrane potential is the electric potential across the plasma membrane. The cell is in resting potential when it is at rest and not firing action potentials. An action potential...
Trace the sequence of events in the axon when an action potential is generated. Action potential is all or nothing; A stimulus-induced depolarization must reach threshold to trigger AP ? RAPID DEPOLARIZATION is caused by opening of voltage-gated Na+
channels ? REPOLARIZATION caused by closure of Na channels and delayed opening of K channels (briefly results in overshoot, at which point the cell is more polar than it was prior to the action potential, before stabalizing.
Why is the resting potential negative and not zero? Were there no gradient across the plasma membrane, it would be impossible to create an action potential by allowing ions to diffuse into the cell. Thus, the neuron would not be able to function...
Distinguish between ligand and voltage gated ion channels. Voltage-gated ion channel - open or close in response to a change in the voltage across the plasma membrane. Ligand gated ion channel - open or close depending on the presence or absence of a
What is the extracellular fluid compartment
The extracellular fluid compartment is comprised of areas outside of cells that contain fluid
particular chemical that binds to the channel protein.
What is saltatory conduction? What is its benefit? Saltatory conduction is a form of rapid impulse propagation that occurs when action potentials are transmitted along myelin-wrapped axons. An action potential is generated at a node of Ranvier, and then
Distinguish among diffusion, facilitated diffusion, osmosis and active transport
Diffusion is the process of random movement towards a state of equilibrium
quickly than in non-mylinated sheets.
How can neurotransmitter be cleared from the synapse? 1. enzymes may destroy the neurotransmitter. 2. the neurotransmitter may diffuse away from the cleft, or 3. be taken up by active transport into nearby cell membranes.
What happens if neurotransmitter is not cleared from the synapse? if a neurotransmitter remained in the synaptic cleft for an extended period of time, the postsynaptic membrane would become saturated with neurotransmitter, and receptors would be...
and would be unresponsive to short-term changes in the presynaptic cell. the more discrete each separate neuronal signal is, the more information can be processed.
Distinguish between the parasympathetic and sympathetic nervous systems. Parasympathetic nervous system - resting and digesting division. promotes nonemergency functions and energy conservation. Sympathetic nervous system - fight or
What is her total intracellular fluid weight
In human beings, 66% of the body's water is found in the intracellular fluid, while 33% is found in the extracellular fluid
Reduces deviations in a regulatory system
uterine contractions by oxytocinoxytocin; drug addiction; sex drive
In which direction will net diffusion of the solute occur
equilibrium what will be the concentration of solute (number of molecules per ml of water) in compartment B
Water will move from A to B
What is Fick’s law
Describe the major factors that control net diffusion
How do negative and positive feedback loops contribute to homeostasis
In the case of negative feedback systems counteracts the original change in the variable being controlled
Distinguish between endocrine and exocrine glands
Endocrine glands are ductless glands that secrete hormones into the intracellular fluid
Distinguish between fat-soluble and water-soluble hormones
Peptide (protein) hormones, like insulin, and most amino acid derived hormones are water soluble
Where are the parathyroid glands located
On the surface of the thyroid glands (in the neck)
Where are steroid hormones produced
Steroids are produced in the adrenal cortex, as
Which endocrine gland stores but does not produce hormones
The posterior pituitary gland stores hormones produced in the hypothalamus
Which endocrine gland is associated with the flight or fight response
the adrenal gland, just above the kidney, releases the hormone epinephrine
What hormones play a role in calcium homeostasis
Calcitonin reduces blood calcium
A few days before menstruation, the anterior pituitary begins to increase its secretion of FSH and Lh. In response, some 10 to 20 follicles being to mature in the ovaries, and increase their production of estrogen. After about a week, all but one follicle withers away. Estrogen exerts negative feedback control on the pituitary until day 12, when it exerts positive control. Causes a surge in LH and FSH, which causes follicle to rupture and release its egg, and the... (character limit exceeded)
How do birth control pills work
What are some common features of steroid hormones
Steroid hormones such as testosterone and estrogen are derivatives of the steroid cholesterol
What is meant by up- or down-regulation of hormone receptors
Down-regulation occurs when continuous high levels of a hormone can decrease the number of its receptors
? First 21 pills contain a combination of synthetic estrogen and progesterone hormones ? Pill ?tricks?the body into thinking its pregnant ? Stops ovulation, thickens cervical mucus, and prevents fertilization
How long is the normal ovarian cycle? When does ovulation occur About 28 days long, although it varies. Ovulation occurs in the middle of the cycle, approx. day 14.
What factors trigger birth both hormonal and mechanical stimuli contribute to the onset of labor. Progesterone inhibits and estrogen stimulates contractions of uterine muscle. Toward the end of the third trimester, the estrogen-progesterone...
Why are some receptors located in the interior of cells
Receptors for water-soluble hormones are on the cell surface, and receptors for lipid-soluble hormones are inside the cell, because lipid-soluble hormones can diffuse through the phospholipid bilayer
How does the structure of endocrine glands facilitate their function
Endocrine glands are richly vascularized (have many blood vessels), which is essential to their mode of secretion
mechanical stimuli come from the strechin of the uterus by the fetus and the pressure of the fetal head on the cervix. Increase the release of oxytocin by the posterior pituitary. this positive feedback loop converts weak false labor contractions into stronger labor contractions.
Where in the female reproductive tract does fertilization occur Where does
after fertilization, the zygote becomes a blastocyst after its first few cell divisions. At this point, it is still in the oviduct. It later moves to the uterus, where it attaches itself to the epithelial lining of the uterus, the endometrium, and burrows into it in a process called implantation. It then interacts with the endometrium to form the placenta.
temporary endocrine structure which produces estrogen and pro-estrogen in the uterus of females. It is formed when follicle cells continue to proliferate and form a mass of endocrine tissue after ovulation occurs.
epithelial lining of the uterus.
sperm are stored in the epididymis, which rests on top of the testis.
its release is triggered by gonadotropin-stimulating hormone. secreted in the anterior pituitary. In males, it enhances the production of androgen binding protein in the Sertoli cells of the testes, playing a vital role in spermatogenesis. In females, FSH stimulates the growth and recruitment of immature Ovarian follicles in the ovary.
Menstrual (uterine) cycle
the ovarian cycle and consists of a buildup and then breakdown of the endometrium (the epithelial lining of the uterus)
lasts about 28 days in human females. During the first half, at least one primary oocyte matures into a secondary oocyte and is expelled from the ovary (ovulation). During the second half, cells in the ovary that were associated with the maturing oocyte develop endocrine functions and then regress if the egg is not fertilized.
tissue that connects fetus to uterus wall. provides it with nutrients, etc.
secretes 30% of semen volume. alkaline, so it neutralizes the acidity in male and female reproductive tracts to make these environments more hospitable to sperm. also secretes a clotting enzyme that causes semen to convert into a gelatinous mass, facilitating its propulsion into the upper regions of the female reproductive tract.
Secondary oocyte/Secondary spermatocyte
formed after primary oocyte/speramtocyte undergoes meiosis 1. 2n.
product of the male reproductive system, includes sperm, plus a mixture of fluids and molecules that support sperm and facilitate fertilization.
tightly coiled tubules within the testes, where spermatogenesis takes place.
What are the four major structural components of the neuron
Cell body - contains the nucleus and most of the cell's organelles
envelops, nourishes, and protects developing sperm cells.
disfiguring birth defects or malformations
sperm are delivered to the urethra through the vas deferens, which joins the urethra behind the bladder.
Why is the resting potential negative and not zero
Were there no gradient across the plasma membrane, it would be impossible to create an action potential by allowing ions to diffuse into the cell
How can neurotransmitter be cleared from the synapse
What happens if neurotransmitter is not cleared from the synapse
if a neurotransmitter remained in the synaptic cleft for an extended period of time, the postsynaptic membrane would become saturated with neurotransmitter, and receptors would be constantly activated
A heartbeat begins with an action potential in the sinoatrial node. This action potential spreads throughout the cells of the atria, causing them to contract in unison. This action potential is conducted through the ventricular muscle mass by noncontractile cardiac muscle cells. This stimulates the atrioventricular node after a short delay, which generates action potentials that are conducted to the ventricles via the bundle of His, resulting in contraction of the ventricle.
Given EDV (end diastolic volume), ESV (end systolic volume), and HR (heart rate), how do you calculate SV (stoke volume), CO (cardiac output), and EF (Ejection fraction)? What are normal resting values for SV, CO, and EF? On average, how often does an RBC pass through the heart
Ejection faction SV/EDV. Ratio of blood that stays in heart per beat to the blood that stays in the heart. A value of less than .4 results in heart failure.
Starting with the outermost, name the three types of ??cardium? and the function of each.
outside the heart. protects the heart.
heart muscle responsible for pumping blood; connective tissue for support and nerve conduction
input into the central nervous system
lining of the heart chambers. smooth surface minimizes blood turbulence during pumping
During one minute, approximately how much time is spent in diastole and how much is spent in systole
output from the central nervous system
So, the heart is at rest (in diastole) about 37.5% of the time (.3/.8)(100), or 22.5 seconds every minute. The heart is contracted (in systole) 37.5 seconds every minute.
Compare and contrast atrial and ventricular contraction in terms of strength, length, timing, valve activity, and maximum blood pressure. Atria contract before ventricles do. Ventricles are thicker, more powerful, and contract for longer than atria, as they are responsible for moving the blood throughout the body and lungs, while atria only push blood into the ventricle. When the ventricles contract, the atrioventricular valves close to prevent backflow.
What are the major differences between oogenesis and spermatogenesis in humans
Spermatogenesis results in 4 functional sperm cell for every primary spermatocyte, while oogenesis results in only one functional ovum for every primary oocyte, and three nucleus-containg polar bodies
Note that the left ventricle is thicker than the right ventricle. Although both ventricles pump the same volume of blood, the left ventricle must pump blood over a much greater distance.
How would a massive drop in blood volume affect CO? Why would tachycardia (abnormally fast heart rate) be expected as a result A massive drop in blood volume would result in a drop in stoke volume. To maintain cardiac output despite lowered stroke volume, the heart rate would have to increase to abnormally fast rate. Remember that CO = SV*HR.
What factors affect SV
Where in the seminiferous tubule are spermatogonia located
Spermatogonia reside in the outer layers of the epithelium that lines the tubules
What is the function of Leydig cells
Leydig cells in the tissue between seminiferous tubules in the testis produce male sex hormones
At what stage of meiosis are primary spermatocytes in
Primary spermatocytes are in prophase 1 of meosis
What hormone controls levels of testosterone
? Back pressure on ventricle (afterload)-minor except in people with high blood pressure.
What factors can influence HR? What hormones, if any, regulate these factors
At what stage of meiosis are primary oocytes
Primary oocytess are in prophase 1 of meosis
? blood composition: aldosterone, ADH
What is the sequence of events in the conducting system (nervous tissue) of the heart through one cardiac cycle? Correlate these events with the signals on an EKG. P corresponds to the depolarization of the atrial muscle, which occurs after the...
Ventricular fibrillation (abnormal EKG)
What factors trigger birth
both hormonal and mechanical stimuli contribute to the onset of labor
Where in the female reproductive tract does fertilization occur
? If EKG is flat line ?no electrical activity and defibrillation will be useless
Resistance to blood flow is regulated primarily in which type of vessel? In these vessels, how is blood flow to an organ...
Which type of vessel is most elastic and why is this important The walls of veins are more expandable than the walls of...
Which type of vessel is least robust (against pressure increase, stresses, etc) and how is its inherent weakness...
Why does the net fluid flow between the capillaries and interstitial fluid reverse as the blood passes through a...
development of the blastocyst begin
Fertilization occurs in the oviduct
If there were no osmotic gradient between the capillary and the interstitial fluid, blood volume would decrease every time blood traveled through the the capillaries.
How do the mechanisms promoting fluid flow through arteries and veins differ The elastin fibers in arteries are stretched during systole, and thereby store some of the energy imparted to the blood by the heart. Elastic recoil during diastole...
How do viscosity, vessel length, and vessel diameter affect the total peripheral resistance?Which one of these factors can be most rapidly changed
Diameter can be most easily changed, by muscular constriction of arteries.
What hormones can alter blood pressure? What tissue or organ does each target? What is its effect on that tissue or organ, and how does this change blood pressure Epinephrine is released from the adrenal medulla during massive sympathetic activation stimulated by a fall in arterial pressure of by a fight-or-flight activation. Angiotensin is produced when blood pressure in the kidneys falls. Angiotensin stimulate contraction of blood vessels, result in increase in... (character limit exceeded)
Hormones can cause the constriction of arterioles located in peripheral tissues (extremities) or in tissues whose function need not be maintained continuously. By reducing blood flow in those arterioles, hormones increase central blood pressure and blood flow to essential organs.
How do ordinary movements such as walking contribute directly to circulation In veins below the heart, the most...
What is hypertension and how is it defined High blood pressure. Blood pressure of 140-159/90-99.
How might hypertension cause damage to organs such as the brain or tissues such as coronary arteries In a case of...
What are the cellular components of blood? What are their functions? Their relative abundance within blood
What are the phases of the cardiac cycle and what happens during each
Describe the muscular, valve, fluid, and electrical activity associated with each
Platelets Blood clotting. Between 250,000 and 400,000.
What are the major components of plasma? What are their functions
End diastolic volume
amount of blood in left ventricle at end of diastole
End systolic volume
amount of blood left in left ventricle after systole
number of heart beats per minute
The difference between EDV and ESV (EDV-ESV)
a hormone that increases the reabsorption of sodium and water and the release (secretion) of potassium in the kidneys.
atrioventricular (AV) node
sends action potential impulses along conducting fibers; causing the ventricle to contract.
atrioventricular (AV) valve
valve between the atria and ventricles, prevent backflow of blood into the atria when the ventricles contract.
a condition that impairs the heart's ability to supply the body with blood.
supplies the head and neck with oxygenated blood
when the ventricles relax
the minimum pressure that causes intermittent flow through the artery.
red blood cells.
the proportion of blood volume that is occupied by red blood cells.
Remember that CO
fragments of megakaryocyte cells. No organelles, but contain enzymes and chemicals necessary for sealing leaks in blood vessels and initiation of blood clotting.
carries blood from heart to lungs
carries blood from lungs to heart
modified cardiac muscle fibers that do not contract, but conduct action potentials
backward flow of blood (in the wrong direction)
– heart rate
– blood pressure
sinoatrial (SA) node
the primary pacemaker of the heart. A nodule of modified cardiac muscle cells, located at the junction of the superior vena cava and the right atrium.
– blood composition
What is the sequence of events in the conducting system (nervous tissue) of the heart through one cardiac cycle
Correlate these events with the signals on an EKG
supplies blood to the head and arms
the minimum pressure necessary to compress an artery so that blood does not flow through it at all.
a heart rate that exceeds the normal range for a resting heartrate
total peripheral resistance (TPR)
Total Peripheral Resistance = (Mean Arterial Pressure - Mean Venous Pressure) / Cardiac Output
is the outermost layer of a blood vessel. It is mainly composed of collagen. The collagen serves to anchor the blood vessel to nearby organs, giving it stability.
Which type of vessel is most elastic and why is this important
The walls of veins are more expandable than the walls of arteries, so blood tends to accumulate in the veins
Which type of vessel is least robust (against pressure increase, stresses, etc) and how is its inherent weakness associated with its function
Arteries have many elastin fibers and smooth muscle fibers, allowing them to withstand high pressures
How do the mechanisms promoting fluid flow through arteries and veins differ
The elastin fibers in arteries are stretched during systole, and thereby store some of the energy imparted to the blood by the heart
These variables are described in Fick's law Q=DA((P1-P2)/L) , where Q is the rate of diffusion for a particular substance, D is the diffusion coefficient, characteristic of the diffusing substance, the medium, and the temperature, A is the cross-sectional area, P1 and P2 are the partial pressure of the gas at the two locations, and L is the distance between the two locations. The body has adapted to allow for optimal gas exchange, for example, by increasing the... (character limit exceeded)
What are the principal functions of the respiratory system To facilitate gas exchange. Cells need to obtain O2 to produce an adequate supply of of ATP by cellular respiration. CO2 is an end product of cellular respiration, and must be removed from the body to prevent toxic effects.
resistance of blood to flow
How do ordinary movements such as walking contribute directly to circulation
In veins below the heart, the most important force propelling blood towards the heart is the squeezing of veins by the contractions of surrounding muscles
What is hypertension and how is it defined
High blood pressure
How might hypertension cause damage to organs such as the brain or tissues such as coronary arteries
In a case of hyptertension, peripheral vascular resistance increases, which leads to an increase in diastolic pressure, which can cause blood vessel damage
How is gas diffusion between the lung and the blood maximized
The respiratory system creates the optimal situation for the diffusion of O2 into the bloodstream from the atmosphere along its concentration gradient, and the diffusion of CO2 out of the bloodstream along its concentration gradient, by altering variables that affect the rate of gas diffusion
volume of air reaching alveoli each minute. (Tidal volume - dead space volume) X (respiration rate)
What are the principal functions of the respiratory system
To facilitate gas exchange
the sites of gas exchange in the human lung.
Branches of the bronchi. The bronchioles terminate by entering the circular sacs called alveoli. Control of airflow resistance and air distribution in the lungs is controlled by the bronchioles.
transfer of gases between lungs and blood across membrane
movement of gases via blood, oxygen-rich from lungs to tissue, CO2 rich from tissue to lungs
transfer of gases between tissues and blood , across membrane
conducts air into the lung. No gas exchange occurs here.
enzyme that facilitates the transformation of carbon dioxide to bicarbonic ions, and vice versa.
connect adjacent alveoli and equalize air pressure
consume microbes and dust particles
a protein consisting of four polypeptide subunits. Each of these polypeptides surrounds a heme group- an iron containing ring structure that can reversibly bind a molecule of oxygen, so a molecule of hemoglobin can bind up to four molecules of oxygen. Increases the capacity of blood to transport oxygen by about sixty-fold.
muscles that run between the ribs.
area of lower brain that receives chemosensory information from the blood, and stimulats change in breathing rate to match metabolic demand.
What determines whether inhalation or exhalation occurs
When a person is at rest, inhalation is an active process and exhalation is an active process
Cells lining the airways produce sticky mucus that captures bits of dirt and microorganisms that are inhaled. Other cells lining the airways have cilia whose beating continually sweeps the mucus, with its trapped debris, up toward the pharynx, where it can be swallowed or spit out. This phenomenon is called the mucociliary escalator.
What is the shape of the diaphragm when it is relaxed
Convex, or dome-shaped
oxygen-binding molecule found in muscle cells. Higher affinity for oxygen than hemoglobin does, so it picks up and holds oxygen at lower partial pressure of oxygen values than hemoglobin. It acts as an oxygen reserve, and allows muscles to save oxygen for times when metabolic demands are high and blood flow is interrupted.
Which cells in the lung produce surfactant and what is the purpose of surfactant
Type II Alveoli cells produce surfactant
Partial pressure of oxygen
determined by multiplying the total barometric pressure of an area times the percentage of oxygen in that area. For example, at sea level, the barometric pressure is 760 mm Hg, and the air is 20.9% oxygen, so the partial pressure of oxygen is (760 mm Hg)(.209)= 159 mm Hg.
tidal volume X respiratory rate.
How is oxygen transported in the blood
Trace the steps from oxygen pick-up in the lung to oxygen drop off in the tissues
the amount of air that moves in and out of the lung per breath, when the individual is at rest.
How is carbon dioxide transported in the blood
Trace the steps from carbon dioxide pick-up in the tissues to carbon dioxide drop-off in the lung
actively moving the respiratory medium over the gas exchange surfaces (breathing) exposes those surfaces regularly to fresh respiratory medium containing maximum O2 and minimum CO2 concentrations. Thus, the concentration gradient is maximized.
What controls the affinity of hemoglobin for oxygen
Various factors influence the affinity of hemoglobin for oxygen, including the chemical composition of hemoglobin, pH, and the presence of 2,3 bisphosphoglyceric acid (BPG)
What are the major functions of the kidney
What is the effect of a left-ward shift in the oxy-hemoglobin dissociation curve on hemoglobin affinity for oxygen
A leftward shift in means that the hemoglobin is holding on to oxygen at lower partial pressures of oxygen
Which blood gas is the primary control for breathing rate
Experiments in which subjects breathe air with different partial pressures of oxygen and partial pressure of carbon dioxide have lead to the conclusion that humans are remarkably insensitive to falling blood levels of oxygen, but very sensitive to increases of carbon dioxide in the blood
a hard working muscle) is able to get more oxygen from the blood
A metabolically active tissue will have a low partial pressure of oxygen, as it will be consuming oxygen in cellular respiration
In the control of breathing rate, what is the input and output in the feedback loop
Change in partial pressure of gases (principally CO2) in the blood stimulates changes in breathing rate
? Vitamin D -converts to its active form
What is the functional unit of the kidney and how many are there in each kidney The nephron. A common estimate is that there are 1 million nephrons per kidney.
- juxtamedullarynephrons (20%) - long LH
How much oxygen do the kidneys consume per day 1/4 of resting oxygen consumption.
What percentage of the 180 L of blood filtered daily by the kidney is excreted as
urine 2 to 3 liters of urine. So, between 1 and 1.5% of blood.
Name the parts of the nephron and their functions.
? Peritubular capillaries -reabsorption of water and various solutes from renal tubule
What two components of blood are not filtered by the kidney. Blood cells and proteins do not...
Where in the nephron is blood filtered Glomerulus.
Where in the nephron are most filtrate substances (e.g. glucose, salts) reabsorbed Most of the...
What is the purpose of the Loop of Henle Create a concentration gradient in the interstitial...
Distinguish between the functions of the distal convoluted tubule and the proximal convoluted tubule
Distal convoluted tubule - final resorption of water; heavily hormone regulated (aldosterone); secretes wastes into the urine (including waste substances such as urea that were passively reabsorbed)
Distinguish between the ascending limb and descending limb of the Loop of Henle
What is the functional unit of the kidney and how many are there in each kidney
? LH ascending limb:impermeable to water, active transport of ions (especially sodium)
Why does the kidney require energy to filter blood It engages in active transport of ions, particularly Na+, into the interstitial fluid and out of the glomerular filtrate.
Where in the nephron are water and ion (e.g. Na+) re-absorption primarily regulated The loop of Henle.
Name the four mechanisms of how water and blood pressure are controlled by the kidney.
How much oxygen do the kidneys consume per day
1/4 of resting oxygen consumption
2 to 3 liters of urine
? ANP and BNP - Atrial natriureticpeptide and brain natriureticpedtide - Released by atrial cells and ventricular cardiac cells when blood volume and/or blood pressure is too high - closes sodium channels, reducing sodium resorptionand therefore reducing water resorption, and thus reducing blood volume and pressure
Distinguish between renin, angiotensinogen, angiotensin I and angiotensin II
Where in the nephron is blood filtered
glucose, salts) reabsorbed
Most of the glomerular filtrate is reabsorbed by the proximal convoluted tubule
What is the purpose of the Loop of Henle
Create a concentration gradient in the interstitial fluid of the renal medulla by a countercurrent multiplier mechanism
Renin - released by the kidney if blood pressure is falling and arteriole dilation does not keep the glomerular filtration rate from falling. Renin acts on a circulating protein to convert it into an active hormone called angiotensin.
How does ADH (vasopressin) act on the kidney to raise blood pressure
? ADH (peptide secreted by the posterior pituitary) increasesthe water permeability of the kidney the water permeability of the kidney collecting ducts, thus making water recovery and concentration of the urine possible
What endocrine gland produces aldosterone and how does it cause the kidney to conserve sodium and water Released by the adrenal cortext. Aldosterone stimulates K+/Na+pump to retain Na +and excrete K +in distal convoluted tubule; water retention
What happens in the kidney to increase blood pressure as a result of dehydration
Why does the kidney require energy to filter blood
It engages in active transport of ions, particularly Na+, into the interstitial fluid and out of the glomerular filtrate
Na+) re-absorption primarily regulated
The loop of Henle
? Drinking water will bring blood pressure back to normal
Why is the kidney a major site of blood pressure control The kidney must maintain a constant high glomerular filtration rate. If blood pressure falls too much, it is unable to maintain GFR and kidney failure can occur.
What endocrine gland produces aldosterone and how does it cause the kidney to conserve sodium and water
Released by the adrenal cortext
a class of membrane proteins that form water channels.
completely surrounds the glomerulus and collects the filtrate
collects urine from the nephrons and delivers it to the renal pelvis. Adjusts concentration of urine; excretes waste into urine.
Why is the kidney a major site of blood pressure control
The kidney must maintain a constant high glomerular filtration rate
drain glomerulus capillaries. The only capillaries in the body that are drained by an artery.
a dense ball of capillaries which is highly permeable to selected substances but impereable to large molecules (cells, protein)
Efferent arteriole from the glomerulus branch to form the peritubular capillaries. intertwine around the renal tubule. these capillaries reabsorb most of the filtrate, re-join, and eventually enter the renal vein and leave the kidney
outer region of kidney
inner region of kidney
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