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("has holes"/ is pourous)
Examples: Comb Jellies (NOT jellyfish)
Examples: Anemones, Jellyfish, Corals, Hydras
Examples: Flatworms, Tapeworms, Planaria
Examples: Leeches, Earthworms, Christmas Tree Worms, Fanworms
Examples: Ascaris, Hookworms, Loa Loa
Examples: Mussels, Scallops, Squid, Snails, Octopus, Cuttlefish
(Jointed-foot) (Most diverse phylum)
over 2/3 of animals are arthropods
Examples: Grasshoppers, Horseshoe Crabs, Tarantulas, Ticks, Shrimp, Blue Crabs, Scorpions, Centipedes
(Spiny Skinned) (All marine animals)
may be most numerous animal?
Examples: Sand Dollars, Sea Urchins, Sea Cucumbers, Sea stars, Sea biscuits
Examples:Tunicates and Sea Squirts
Examples: Lancelets, Amphioxus
Class Chondrichthyes; Subphylum Vertebrata; Phylum Chordata
Examples: Sharks, Skates, Rays
Class Osteichthyes; Subphylum Vertebrata; Phylum Chordata
Examples: Seahorses, Flouder, Bluegill
Examples: Frogs, Toads, Salamanders
Examples: Snakes, Turtles, Lizards
Examples: Owls, Ducks, Hawks, Robins, Penguins
Examples: Whales, Apes, Humans, Kangaroos, Platapus
-In fossil record 200 MYA
-Protective shells, of keratin and bone. Ribs fused to shell
-No teeth, tough beak for food grabbing
-No temporal openings on skull (anapsid)
-95% of all known living reptiles
-Order Squamata: 2 main characterisitcs
A) Modified skull w/ moveable joints
B) Paired copulatory organs in males
-Completely limbless, many vertebrae
-No pectoral/pelvic girdles
-No external ear (internal ear)
-Can hear in low frequency
-heat sensors, and some good binocular vision
-Unchanged for 200 MY
-Three families (alligators and caimains, crocodiles, gavials)
-Teeth in sockets, typical or archosaurs
-Secondary palate present, breath and eat at the same time
-4-chambered heart like birds and mammals
-Archosauria dominated life on land during Mezosoic
-Major extinction events:
A) 244 MYA- 90% of living org. went extinct
B) 65 MYA- 25% of living org. went extinct (inc. dinosaurs)
-Both show growing evidence that earth was struck by meteor
-Most successful vertebrate on land
-Characterized by feathers
-Considered living dinosaurs
enzyme that catalyzes carbon fixing step
-low affinity to CO2 = high concen. of CO2 required
-also catalyzes Photorespiration
RuBP + O2------> 1 PGA + 1 PGAL (TOXIC)
--requires energy to detoxify PGAL
Photorespiration increases with temperature
Mescaline - from peyote cacti (Lophophora)
Opium - from poppies (Papaver)
Cocaine - from coca plants (Erythroxylum)
Caffeine - from coffee plants (Coffea)
Plants are multicellular, autotrophic organisms
What does the retention of the zygote within the female gametangium distinguish?
distinguishes plants from other groups of photosynthetic eukaryotes
is considered to be a key evolutionary innovation enabling plants to colonize land.
Plants form a monophyletic lineage (i.e., they are all descendants of a common ancestor that made the transition from an aquatic to a terrestrial environment).
DNA sequence data indicates that the ancestors of plants belong to the charophyte lineage, which is a lineage of “green algae”.
There is fossil evidence of plant life on land at least 430 million years ago.
characterized by three additional key evolutionary innovations
1. the evolution of specialized conducting cells called tracheids, which enabled long-distance transport of water and solutes.
characteristic of the lycophytes, pteridophytes (i.e., ferns and their relatives), gymnosperms, and angiosperms, which collectively are known as the vascular plants.
Tracheids do not occur in the mosses, hornworts, or liverworts.
2. the evolution of seeds. A seed is a dispersing unit that contains the embryo, a nutritive tissue, and a protective seed coat.
Seeds are characteristic of the gymnosperms and angiosperms, which together are known as the seed plants.
3. the evolution of flowers, carpels, and endosperm.
Flowers facilitate pollination
Carpels enclose and protect the ovules
Endosperm nourishes the developing embryo.
Flowers, carpels, and endosperm are characteristic of the angiosperms, which also are known as the flowering plants.
All sexually reproducing organisms, including plants, exhibit sexual life cycles.
Though all sexual life cycles share some basic features, there is great variation in the details of the life cycles across groups of organisms.
the two processes define the boundaries of the haploid and diploid phases of the life cycle.
sexual reproduction generates genetic variation, which is important in evolution.
In the haploid phase of the life cycle, there is not an intervening multicellular stage in humans, as there is in plants.
During the diversification of plants, there has been a from life cycles in which the gametophyte is larger, longer-lived, and more self-sufficient to those in which the sporophyte is larger, longer-lived, and more self-sufficient.
Such a shift is evident, for example, in comparing the life cycles of mosses, ferns, and gymnosperms.
In the typical moss life cycle, the multicellular gametophyte is photosynthetic and free-living
the multicellular sporophyte is attached to, and is completely dependent for its nutrition on, the multicellular gametophyte.
In the typical fern life cycle, both the multicellular gametophyte and multicellular sporophyte are photosynthetic and free-living
the multicellular gametophyte is usually small, delicate, and short-lived, whereas the multicellular sporophyte is larger and much longer-lived.
Thus, the multicellular sporophyte is what we typically see when we observe ferns in the field.
In the typical gymnosperm life cycle, the multicellular sporophyte is photosynthetic and free-living
the multicellular gametophyte is attached to, and is completely dependent for its nutrition on, the multicellular sporophyte.
the multicellular sporophyte is larger and longer-lived, and is what we typically see when we observe gymnosperms in the field.
Note also that in the gymnosperm life cycle, two distinct types of spores are produced by meiosis, called microspores and megaspores.
Microspores give rise via mitosis to multicellular male gametophytes, which then give rise to the male gametes (i.e., sperm).
megaspores give rise via mitosis to multicellular female gametophytes, which then give rise to the female gametes (i.e., eggs).
There are more than 230,000 known species of angiosperms, which is by far the largest number for any plant group.
In most terrestrial ecosystems, angiosperms account for most of the photosynthetic conversion of radiant energy into chemical energy.
2. sources of food -- The vast majority of our food comes directly or indirectly from angiosperms
3. sources of drugs -- Many angiosperms produce chemicals with significant medicinal properties.
Other angiosperms produce chemicals with significant effects on the human central nervous system.
In angiosperms, the ovules are enclosed within specialized structures called carpels (or pistils)
Angiosperms also exhibit double fertilization and endosperm formation
The vegetative body of a typical angiosperm consists of roots, stems, and leaves.
Roots are involved in water and nutrient uptake and in support (or anchoring).
Stems are involved in the transport of water, nutrients, sugars, etc. between the roots and leaves and in support.
Leaves carry out photosynthesis.
The upper and lower leaf surfaces are covered by a waxy cuticle to prevent water vapor from diffusing out of the leaf.
the cuticle also prevents CO2 from diffusing into the leaf.
This situation represents a major dilemma for plants, as CO2 is required for photosynthesis.
This dilemma is resolved through the presence of adjustable pores, or stomata, in the leaf epidermis (singular = stoma).
The stoma (or pore) is surrounded by two specialized epidermal cells called guard cells.
1. active transport of potassium ions into the guard cells from the surrounding epidermal cells (remember that active transport requires energy),
2. net movement of water into the guard cells to maintain osmotic balance,
3. increased turgidity of the guard cells
A reverse process, first involving passive diffusion of potassium ions out of the guard cells into the surrounding epidermal cells, results in stomatal closing.
they are their main photosynthetic pigments
as their photosynthetic storage product.
retained within the female gametangium, where it develops into an embryo.
The female gametangium is the structure within which the egg is produced.
Thus, the developing embryo is protected by the tissues of the parent plant.
Traits such as tracheids, seeds, and carpels serve as adaptations to prevent desiccation in the dry terrestrial environment.
-the haploid phase of the life cycle is called the gametophyte generation
-the diploid phase is called the sporophyte generation.
Thus, the life cycles of plants are said to involve an “alternation of generations”.
as are most (but not all) ferns.
*Cereal grains, legumes, and virtually all so-called vegetables, fruits, and nuts are obtained from angiosperms.
Most spices are also obtained from angiosperms.
In addition, most non-alcoholic and alcoholic beverages are made from angiosperms.
Quinine - used in treating malaria
Curare - used as a muscle relaxant in open-heart surgery
Diosgenin - used as a precursor to the active ingredient in oral contraceptives
Examples of chemicals with significant effects on the human central nervous system are ______________________.
*Many of these chemicals are likely used by plants as defenses against being eaten by animals.
-soil has chemicals in it that signals the seeds to germinate
the multicellular male gametophyte is the pollen grain
the multicellular female gametophyte is the embryo sac.
xylem is involved in the transport of water and nutrients
phloem is involved in the transport of sugars produced by photosynthesis and of other compounds.
Two physical features of guard cells are important to the mechanism of stomatal opening
1. specialized bands of inelastic cellulose microfibrils
2. the cell wall of each guard cell is thicker on the side close to the stoma than on the side away from the stoma.
are oriented perpendicular to the long axis of each guard cell
Stomata thus regulate the balance between CO2 uptake and water vapor loss.
soil water and ions "flood" into the cortex
--at epidermis: plasma membrane proteins actively pump selectede ions across the endodermis and into the xylum (water follows by osmosis) creating hypertonic solution in the xylum
1) root pressure: influx of water into xylem creates hydrostatic pressure that pushes the water and nutrients up
2) Transpiration: as water evaporates through the stomata, it creates a negative pressure that pulls water up through the xylem
blue light causes the stomata to open/close
potassium and chloride are "pumped" into gaurd cells andd water follows by osmosis
CO2 + RuBP (5 carrbon) -----(rubisco)-----> 2 PGA (3 carbon) ----> Sugar (6 carbon)
light dependant reactions occur in the mesophylls of the leaf
Calvin cycle occurs in the Bundle Sheath Cells
Carbon fixation occurs in the mesophyll cells
CO2 + PEP-->OOA -enzyme is PEP carboxylase
OOA---> bundle sheath cells
OOA---->CO2 + Pyruvate
CO2 + RuBP--(rubisco)-->2 PGA---->sugar
Pyruvate--------> PEP--------->back to mesophyll
-high affinity to CO2
light independant reactions and light dependant reactions occur in the same cells
Stomata only open at night
CO2 + PEP --------> Malate (4 carbon)
malate-----> CO2 + PEP
CO2 goes throught calvin cycle to create a sugar
Translocation: from sources to sink
@ source: sugars are moved into ploem and water follows by osmosis creating positive hydrostatic pressure
@sink: sugars move out of phloem and water moves to xylum, creating a negative hydrostatic pressure.
Pollen: male gametophyte of angiosperms and gymnosperms (2 cells)
2 Mechanism of pollen transfer:
wind or animal
lots of pollen
very exposed flowers (small petals and long style and filiment)
flower in early spring
low seed dispersal
grow in clumps
-Benefit for animal: Nector or pollen
-Benefit for Plant: Effeciency and longer distances
1) Flower Color
2) Strong specificity between species
-yellow/blue= insect pollenated
-flower color doesnt block UV light
-white= mostly moth pollenated
-insects cant see red
-very effective pollen transfer
-no competition for the insect
-reduced variation; the more variation in a population the better chance it has to adapt to changes in the enviornment
-inbreeding depression: reduction in fitness due to ehanced expression of bad recessive alleles
ease of reproduction
-plants that live in harsh enviornments
1) seperation between male and female reproductive structures
-temperal (mature at different times) -spacially
2)Dioeccious (seperate male and female plants)
3)self incompatability (if pollen is coming from plant, stigma secretes chemical that prevents pollen from germinating)
the embryo secretes a horomone ( a chemical secreted by one tissue that causes a response in another tissue) called Auxin
-causes the ovary to develope into fruit
the developement of the fruit without the seeds
-megagametophyte secretes Auxin before pollenation occurs
-new individuals sprout from either stem tissue or root tissue
-stem: rhisomes, runners
Found in pioneer species
-2N megasporocyte ---mitosis--->2N megaspore ---mitosis(3x)--->megagametophyte with egg (2N)
produce large seeds (but few seeds)
-lots of energy
-hard thick seed coat
-tannic acids (tannins)
tannic acid that is stored in the embryo
-interferes with the digestive system
*found in grape peels and gives a tart flavor*
lots of small, easily dispersed seeds
1) produce many wind dispersed seeds
2) fewer seeds with a dispersal mechanism
-use animals as dispersal mechanisms
embryo is 5-20% water
-embryo secretes horomones that causes seed coat to soften and become permeable to water--- absorbs water and swells (breaks the seed coat), apicol meristems become active and first shoot and root starts growing
1) Water *universal requirement*
2) Oxygen *universal requirement*
4) Red light (weeds/pioneer species)
indicates full sunlight (red light does not penetrate into soil very deep because it is quickly absorbed)
can indicate how deep the seed is buried
physical or chemical damage to the seed coat
-passage through mammal gut
-heat--sorotiny (Jack Pine)
-forest fire required for seed of Jack Pine to germinate
directional growth to or away from some enviornmental cue
-affected by Auxin (secreted by apicol meristem and flows down stem or up root)
-causes (stem tissue) or inhibits (root tissue) cell elongation
growth towards the light
-apicol meristems send Auxin down the dark side of the stem
-due to blue light
stem tissue is negative gravitrohic (Auxin accumulates on the down side of stem
root tissue is positive gravitrophic (Auxin is distributed to lower side of root, causes upper side to grow faster
directional growth in response to physical touch
1) epidermal cells at apicol meristem dectect stimulus and send "nerve" impulse to cells on opposite side of stem (cause increase in turgor pressure)
2)Auxin is sent to opposite side
a change in the growth due to light
-Etiolation: plant produces long, thin, pale stems with few pale leaves and no braches
default growth pattern
protein/pigment complex that serves to regulate growth and flowering in response to light (red)
-PR --inactive form, sensitive to red light (660 nm)
-PFR --active form, sensitive to far red light (730 nm)
active--turns on or turns off a process
-tends to turn off etiolation
-regulates germination as well
require day length shorter than some critical value in order to flower
Spring, rarely fall
*long night plant*
require a day length longer than some critical value in order to flower
summer (most northern plants)
*short night plant*
day length has no effect
Tropical (day lenght doesn't vary much)
Pioneer species (enviornment is harsh, so flower when conditions are right)
heterotroph (relies on organic source that was living at one time)
lack cell wall
Cnideria (jellyfish, Hydra, sea anenomes)
Platyhelmenthes (flat worms)
Nematoda (round worms)
Annalida (segmented worms)
1) increase in mobility
2) Increase in size
bilateral symmetry provides directional orientation
-posterior locomotory structures
-anterior sensory and feeding structures
skeletal system--locomotion (muscle contraction)
increase in size
reduces you predators
-way of transporting material in your body
1) level or organization (cell, tissue, or organ)
2) Symmetry (asymmetrical, radial, or bilateral)
3) Developement of the gut
4) Developement of the body cavity
Radial symmetry (more than one way to cut & it be symmetrical)
Bi-lateral symmetry (cephalization)
-all other Phyla
*starfish are considered Bi-lateral because of embryonic devel.
-no gut (porifera: intracellular digestion0
-incomplete gut (Cnideria and Platyhelmenthes)
-complete gut (all other Phyla)
-2 openings, effeciency (assembly line like)
aceolomate: no cavity (platyhelmenthes)
ceolom: all other Phyla
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