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How do plants circulate food, water, and nutrients?
B. vascular tissue of roots
D. root vessels throughout the leaves
E. Plants do not "circulate"; each individual part, roots, stems, and leaves, acquires its own nutrients.
Sugars produced in the leaves of a plant are transported elsewhere in the plant through:
A. the movement of symbiotic bacteria that carry the sugars.
B. the stroma apparatus.
C. sap vesicles.
Roots perform which of the following functions in plants?
D. All of the above are true.
E. Both the first and second answer choices are true, but the third choice is not.
What is the difference (if any) between lateral and apical meristems?
A. Apical meristems are located at the tip of a root or stem; lateral meristems are also found here.
B. Apical meristem cell division results in root or stem length increase; lateral meristem cell division results in stem or root thickening.
C. Apical meristems and lateral meristems are identical; they only differ in terms of plant location.
D. Apical meristems consist of cork cells; lateral meristems consist of cambium cells.
E. None of the above are true.
What are the five parts (from top to bottom) of a leaf?
A. Cuticle, non-photosynthetic epidermal cells, photosynthetic cells, xylem & phloem, and guard cells with stomata
B. Cuticle, photosynthetic epidermal cells, photosynthetic cells, xylem & phloem, and guard cells with stomata
C. Cuticle, non-photosynthetic epidermal cells, photosynthetic cells, xylem & phloem, and cork cells with stomata
D. Guard cells with stomata, xylem & phloem, photosynthetic cells, non-photosynthetic cells, cuticle
E. Epidermis, palisade cells, spongy cells, xylem & phloem, and guard cells
The process of water absorption by plant roots generally relies on ______ across the membranes of cells in ______.
A. osmosis; root hairs
B. active transport; root hairs
C. osmosis; the apical meristem
D. active transport; the apical meristem
E. facilitated diffusion; stomata
The cohesion-tension mechanism (mechanism responsible for the plant to move water up a plant) relies on what process to draw water upwards into the leaves?
A. root growth together with mychorrizae
B. building a greater mineral concentration in the leaf cells than in root cells
C. evaporation through stomata
D. ATP-driven water pumping from the roots
E. breaking hydrogen bonds between water molecules in the xylem
Evaporation from the leaves of a tree pulls water up from the roots as an unbroken column throughout the entire height of the tree. This feat is possible because of which characteristic(s) of water?
A. high heat capacity
B. lesser density as a solid than as a liquid
C. water likes to stick to other water molecules
D. low heat capacity
E. water molecules tend to more more rapidly than other types of molecules
The movement of sugar through the body of a plant requires:
A. active transport of sugar into phloem tissue.
B. active transport of sugar out of phloem tissue.
C. osmosis between xylem and phloem to occur.
D. All of the above are true.
E. None of the above is true.
Which of the following steps of moving sugar in the plant is CORRECT?
A. Sugar is loaded by facilitated diffusion into the phloem from sites of production (primarily leaves).
B. The increased sugar concentration in the phloem immediately causes water to move from xylem into phloem by diffusion.
C. As water movies into the phloem, it increases the fluid pressure inside the phloem.
D. The increased phloem pressure causes the fluid in the phloem to move elsewhere in the plant, such as the leaves.
E. As the sugar is pushed through the plant body, it is moved out of the phloem by protein carriers wherever it is needed.
Asexual reproduction in plants:
A. is energetically more expensive than sexual reproduction.
B. still requires meiosis.
C. requires reproductive cells that are produced in flowers.
D. none of the above
Asexual reproduction is advantageous to plants because:
A. it is a method of increasing the diversity of allele combinations.
B. it is the most adaptive form of reproduction when environmental conditions are unstable and frequently changing.
C. it only requires a single partner to contribute gametes for fertilization.
D. it is more energetically efficient than sexual reproduction.
E. it produces plants that are more resistant to pests and disease than the parent plant.
A. Meiosis, pollination, fertilization, embryo formation
B. Fertilization, meiosis, nuclear fusion, endosperm formation
C. Growth of the pollen tube, pollination, germination, fertilization
D. Meiosis, fertilization, growth of the pollen tube, germination
E. Mitosis, embryo formation, pollination, seed development
In angiosperms, the ______ are the specialized reproductive organs whose main function is to bring together the sperm and egg.
B. pollen grains
Which of the following flower parts interact directly with pollen?
D. The first two choices are correct.
E. The first three choices are correct.
Which of the following flower structures is INCORRECTLY paired with its function?
A. Stamens: produce the male gametes
B. Petals: attract pollinators
C. Sepals: protect the developing flower bud
D. Stigma: surround and protect the female gametes
E. All of the above are incorrectly paired.
Which of the following is a likely way in which plants increase dispersal of their fruit?
A. Fruit that is conspicuously colored
B. Fruit that tastes good
C. Fruit colors that attract female birds
D. The first and second choices are true.
E. The first and third choices are true.
The common term for the action of transferring pollen grains from an anther onto a stigma is:
E. None of the above
Which of the following is NOT a strategy by which plants achieve pollination?
A. Enticing an insect to visit the plant for a food source.
B. Insects find a good place to lay eggs inside the flower
C. Releasing pollen to the wind
D. Releasing pollen into water
E. All of the above are methods by which plants achieve pollination.
Which of the following is NOT contained within the seed?
E. All of the above.
A little girl is playing in a field and picks up a dandelion. She blows on the dandelion and the little "hair parachutes" fly through the air. What exactly just took place, botanically speaking, as she did this?
B. The bushy hairs allowed the fruits of the dandelion to float in the air.
C. The seeds exploded upon exposure to the force of air being applied to the dandelion.
D. She damaged the dandelion structure, killing the plant.
E. She hindered the dispersal of the dandelion outside of its natural range, putting the fruits in harms way.
When, after seed germination, does photosynthesis begin?
A. When the seed coat breaks open
B. When the first foliage is formed
C. When the shoot emerges from the soil
D. The second the seed begins to germinate
E. When the root is formed
When you are seven years old, you scratch your name, 4 feet above the ground, into a 12-foot-tall bamboo plant. You spend the next 10 years in a special home for vandals. When you get out, the bamboo is 24 feet tall. At that time, how far above the ground will your name be?
A. 16 feet
B. 4 feet
C. 8 feet
D. 12 feet
E. 2 feet
Which of the following statements concerning primary and secondary growth is most accurate?
A. Primary growth may occur before or instead of secondary growth.
B. Primary growth causes plants to get taller, whereas secondary growth makes them thicker and stronger.
C. Secondary growth is an alternative means of growth if primary growth conditions are not present.
D. Primary growth is due to division in the lateral meristems, whereas secondary growth is due to division in the apical meristems.
E. All of the above.
Which of the following is a "cluster of active, indefinitely dividing cells"?
B. root meristem
C. shoot meristem
E. Both the second and third choices are correct.
Which of the following is true?
A. Growth in animals is indeterminate.
B. Primary growth is responsible for adding to the thickness of a tree trunk.
C. Apical meristems are responsible for laying down the annual rings of wood in a tree.
D. Meristem cells can develop into any type of plant tissue.
E. Plants always die if they lose substantial portions of their "bodies."
Which of the following is NOT true about secondary growth seen in trees?
A. Cells of the vascular cambium produce a ring of cells toward the outside called the secondary phloem.
B. The vascular cambium lies between xylem and phloem layers in a tree.
C. Cells of the vascular cambium produce a ring of cells in the trunk called the lateral meristem.
D. Wood is actually layers of xylem.
E. Bark is produced by the apical meristem located at the center of the tree.
The scientific term for wood is:
A. primary phloem.
C. secondary xylem.
Which of the following sequences places the steps of the inflammatory reaction in the correct order?
A. cells release histamine, pathogens enter a wound, blood vessels nearby dilate, the skin grows back over the wound, white blood cells engulf pathogens and recruit other WBC's to the area
B. Phagocytes engulf pathogens and recruit other WBC's to the area, blood vessels nearby dilate, cells release histamine, the skin grows back over the wound, pathogens enter a wound
C. blood vessels nearby dilate, macrophages engulf pathogens and recruit other phagocytes to the area, pathogens enter a wound, cells release histamine, the skin grows back over the wound
D. cells release histamine, the skin grows back over the wound, blood vessels nearby dilate, pathogens enter a wound, macrophages engulf pathogens and recruit other phagocytes to the area
E. pathogens enter a wound, macrophages engulf pathogens and recruit other phagocytes to the area, cells release histamine, blood vessels nearby dilate, the skin grows back over the wound
How does non-specific immunity DIFFER from specific immunity?
A. One responds much more quickly than the other.
B. One recognizes specific pathogens while the other does not.
C. One establishes a "memory" of exposure to a pathogen while the other does not.
D. One involves barriers like the skin and mucous membranes while the other does not.
E. All of the above are true, except the fourth answer choice.
Which of the following statements about the inflammatory response is INCORRECT?
A. The release of histamine by mast cells initiates inflammation.
B. Cells lining blood vessels near inflamed tissue become "stickier" to neutrophils.
C. Pain can occur with inflammation, as increased pressure in an inflamed area stimulates local neurons.
D. The release of histamine causes blood vessels to constrict, reducing blood loss in an injured area.
E. Four signs of inflammation are swelling, redness, heat, and pain.
One difference between the non-specific and specific immune system is when you first encounter a new foreign invader, the latter is slower than the former. Why?
A. The non-specific system refers only to your main skin and mucous barriers; of course they act faster, they are on the outside of your body!
B. The non-specific system has a higher number of fighter cells than the specific system; it is simply a matter of numbers.
C. The non-specific system is the stronger of the two, which is why it is able to respond the fastest.
D. The non-specific system has all its components already present; the factors of the specific immune system must first be stimulated into action, and cell division must "ramp up".
E. The non-specific system evolved in organisms first, and thus is better specific to respond to the many foreign agents that could possibly infect an organism.
The role of the stomach with regards to immunity is:
A. to digest the food that microbes otherwise could utilize for energy
B. to dilute microbes to low concentrations with gastric juice
C. to destroy microbes with strongly acidic gastric juice
D. to house competitive microbes which outcompete dangerous pathogens.
E. both C and D
What is the function of the cilia found around the inner surface of the windpipe (in the respiratory tract)?
A. Cilia kill pathogens because they are acidic.
B. Cilia are form a "carpet" that keeps microbes from contacting the wall of the tract.
C. Cilia agitate the windpipe surface, knocking off pathogens so they harmlessly fall into the lungs.
D. Cilia move mucus up and out of the respiratory tract.
E. Cilia produce enzymes that kill pathogens.
Which of the following is an INCORRECT statement about phagocytes?
A. They are found in all forms of animals, from coral, anemones, and snails to birds and humans.
B. They are the first cells to collect at the sight of an injury.
C. They are part of the innate immune system.
D. They recognize and engulf foreign cells.
E. They form memory cells after each encounter with an infectious agent so they can react faster the next time.
Which of the following is NOT true about the way phagocytes destroy pathogens?
A. They present pieces of broken-down pathogens on their surfaces.
B. They are non-specific cells.
C. They produce interferons when they "swallow" bacteria.
D. They ingest microorganisms and kill them within their cells.
Why don't people develop immunity to the common cold?
A. Actually, many people do develop immunity to the common cold and get sick only from bacterial infections.
B. There are at least 200 different viruses that can cause the common cold, and they change over time.
C. Only the non-specific immune system helps individuals fight the common cold; the specific immune system is not an effective defense against viruses.
D. The rhinovirus that causes the common cold has no surface antigens and so can move through the body without being detected.
E. The pathogen that causes the common cold attacks and kills memory cells, continually "erasing" the immune system's memory of it.
Which of the following is NOT a function of antibodies?
A. making holes in the pathogen upon binding
B. cross-linking pathogens together in a clump
C. facilitating phagocytosis
D. attracting complement proteins to "pop" a pathogenic cell
E. blocking the entry of pathogens into body cells
The major difference between T cells and B cells is that:
A. T cells do not interact with the specific immune system, but B cells do.
B. T cells ingest pathogens but B cells explode pathogens.
C. T cells bind to foreign antigens presented by antigen-presenting cells, whereas B cells produce proteins (antibodies) that are secreted and bind directly to the foreign antigens.
D. All of the above are major differences between T cells and B cells.
The role of B cells in the specific immune system is to:
A. make antibodies that bind to antigens on the pathogen.
B. engulf rogue body cells (like cancer cells), destroying them.
C. produce antigens to which T cells can bind.
D. make antigen receptors for use in T cells.
E. move out of the bloodstream and perform most of the phagocytosis at an inflammation site.
Which of the following best explains why you can get a disease you have had before or have been vaccinated against?
A. Mutation in the genes of the pathogen causes the pathogen to have new surface proteins with different shapes.
B. Some disease pathogens can kill memory cells before they have a chance to recognize that the same pathogen is invading the body.
C. Memory cells don't last very long, about 45-100 days.
D. Fragments of pathogens lingering from a vaccine or a previous illness can defeat the specific immune system.
E. Most diseases are caused by a wide variety of unrelated pathogens so immunity against one organism won't protect you from another.
Vaccines are useful because:
A. They contain antibodies that attach to and kill circulating pathogens.
B. Vaccines given at the time of infection help you get well sooner.
C. One vaccine can help protect you against a large number of viral and bacterial pathogens.
D. They stimulate the formation of memory cells primed to recognize a particular pathogen.
E. They help to insure that you will never get sick.
Why is it possible to get the flu during the flu season when you have already been vaccinated for influenza?
A. You are still susceptible to strains of the flu that are not included in the flu vaccine.
B. Vaccinations take several months to years before they work effectively.
C. Vaccines are made to clear your body of pathogenic antibodies and they may sometimes miss killing some of them.
D. Vaccinations depress your immune system for several weeks after you get them, making you more susceptible to "coming down" with the flu.
E. Vaccines don't stimulate the formation of memory cells.
There are many B-cells in your body, each specific for only one foreign antigen at any one time. How does your body manage to produce enough antigen-specific antibodies to fight off major bombardments of infectious agents so that you eventually recover?
A. A B-cell specific to the infectious agent binds the foreign antigen and becomes an antibody producing machine, making enough antibodies itself to fight off all the invaders within your body.
B. The B-cell specific to the infectious agent binds the foreign antigen and engulfs it. It then releases chemical signals to the surrounding B-cells to alter it of its presence and they create the antigen-specific antibodies.
C. The B-cell specific to the infectious agent binds the foreign antigen and alters the cellular part of the immune system (the T-cells) of its presence. It is the T-cells' job to clear the infectious agent through cytotoxic T-cells.
D. The B-cell specific to the infectious agent binds the foreign antigen and proliferates, creating plasma cells that make enough antibodies to fight off the infection.
E. The B-cell specific to the infectious agent binds the foreign antibody and dies. It is then engulfed by macrophages, which activate cytotoxic T-cells to fight off the infection.
Which of the following is not a function of helper T cells?
A. They activate cytotoxic T cells.
B. They recognize antigens presented on phagocytic surfaces.
C. They stimulate B cells to proliferate and produce antibodies.
D. All of the above are functions of helper T cells.
Which of the following events occurs in the chronic (dormant) phase of an HIV infection?
A. The immune system virtually clear the body of viruses.
B. Helper T cells are so few in the body that they cannot activate B or cytotoxic T cells.
C. Common pathogens gain a foothold in the body, causing serious illness
D. HIV viruses remains hidden inside helper T cells.
E. None of the above is correct.
As the human immunodeficiency virus (HIV) begins to kill the host's ______, the host's immune system begins to fail.
A. liver cells
B. spleen cells
C. red blood cells
D. white blood cells
E. All of these are correct answers.
Some diseases are caused when an individual's immune system responds inappropriately to "self" antigens. Diabetes type I, rheumatoid arthritis, MS and others are examples. This is called:
A. cell-mediated immunity
C. clonal selection
During the chronic (dormant) phase of HIV infection:
A. An infected person cannot pass HIV to another person; they aren't contagious.
B. The number of helper T cells dramatically decreases.
C. Ninety-nine percent of the infective viruses are killed in a primary immune response.
D. A person succumbs to common pathogens that are normally kept at bay in healthy individuals.
E. None of the above is correct about the chronic phase of infection.
Making an effective vaccine against AIDS has been difficult because:
A. Many people have a mutation in their T cell receptors that prevent a vaccine from working.
B. It has been difficult to establish whether or not the HIV virus is the causative pathogen for AIDS.
C. Very few researchers are working on an AIDS vaccine.
D. There aren't enough people with AIDS anymore to test potential vaccines on.
E. The surface proteins of the AIDS virus mutate very quickly.
People develop allergies to otherwise harmless substances, such as peanuts, because their immune cells become overly sensitive to the proteins on the substance's surface and attack it as though it was an infectious agent. In order for this process to make sense, which of the following must be true?
A. In order for a person to have an allergic attack from a harmless substance, he or she must have prior exposure to that substance in order to build up specific antibodies that make the reaction to the second exposure so fast and powerful.
B. An allergic attack occurs because the individual just happens to have been infected with a pathogen with similar surface proteins to the harmless substance and activates the secondary response system on upon first exposure of the allergen.
C. In order for a person to have an allergic attack from a harmless substance, he or she must have prior exposure to that substance in order to build up the memory B-cells that make the reaction to the second exposure so fast and powerful.
D. An allergic attack occurs when the innate immune response reacts too powerfully to the harmless substance. This can happen on the first exposure and explains the swelling and fever that often comes with an allergic attack.
E. None of the above is correct.
Mountain pine beetle (MPB), Dendroctonus ponderosae, is native to the forests of western North America…in Colorado for 65 million years
A. Movement within the phloem is halted.
B. Nutrient dispersal is blocked within the tree.
C. Photosynthesis stops.
D. Both A & B.
1) D: The beetles eat the phloem. Phloem transports sugars and water within the tree. If the phloem is destroyed the tree will not be able to distribute sugar appropriately in the tree and the tree will die.
2) B: The researchers wanted to know what was different between the trees that survived and the trees that died. Since resin may help defend the tree against the beetles, they hypothesized that trees that survived may have more resin production. This may mean that they spent less energy on growth and more energy on defense.
A. Trees with larger resin ducts survived more than trees with smaller ducts.
B. Trees with more productive resin ducts are more likely to die.
C. There is no trend and no correlation between resin ducts and tree mortality.
3) A: The graph shows that those trees with the lowest resin duct production and the smallest resin duct area have the highest mortality.
Human actions seem to be changing the historic patterns of beetle infestations.
4) D: All of these are possible. If beetles are reproducing twice as quickly, more trees will likely be impacted and die. If the trees are not able to adapt more quickly, they may go extinct because the beetles are adjusting their tactics more quickly.
They monitored the accumulation of virus in the test tube over time by measuring the amount of p24 proteins produced1. Why was one of the tubes not just HIV virus + cytotoxic T cells?
A) Because cytotoxic T cells don’t need helper T cells to work.
B) Because HIV only infects helper T cells.
C) Because cytotoxic T cells may be able to do the helper T cells job also if the helper T cells are missing.
D) All of the above
1) B, the only cell type which HIV can enter and replicate inside are Helper T Cells.
2) B, there is no viral replication happening in individuals EU2 and EU3 which indicates that these individuals have some type of natural protection.
B, No it doesn't appear that the cytotoxic T cells provide significant protection from the virus, though 3 out of 9 show less of the virus in the cells (LP5, LW1, LW3) I don't think that the lower production is enough to be considered "protection" from the virus, a small section of the small sample didn't produce as many virus's- maybe enough to inspire a new experiment but not enough to qualify as positive protection.
A) The Super Cytotoxic T Cells Hypothesis
B) The Super T Helper Cells Hypothesis
C) Neither hypothesis is supported
D) Both, the results are mixed
B, if we base our decision on EU2 & 3 from question 2, there is no difference in viral load when we add cytotoxic T cells so it is likely that there is something unique about the Helper T Cells. If we look at the other individuals in the graph for #2, there are more individuals with lower viral amounts when Cytotoxic T cells are included so it seems that perhaps they are important in the partial protection of individuals against HIV in circumstances when the Helper T Cells do not hold their special characteristics.
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