Term
|
Definition
| Related species arisen through gene duplication |
|
|
Term
|
Definition
| Creation of additional copy of a gene |
|
|
Term
|
Definition
| Non functional remnants of a functional copy that due to a mutation no longer work. |
|
|
Term
| Give an example of mutation for pseudogene |
|
Definition
| Genes misalign during meiosis, unequal crossing over and recombination occur. |
|
|
Term
|
Definition
| Responsible in patterning the anterior-posterior body axis. |
|
|
Term
| What is the role of the Bicoid protein? |
|
Definition
| Bicoid protein is a regulatory transcription factor that activates genes required for anterior structures. |
|
|
Term
|
Definition
|
|
Term
| Loss of function mutation experiment (Hox) |
|
Definition
| Loss of UBX function result in haltere segment converted to wing. UBX needed for haltere segment specification. |
|
|
Term
| Gene expression pattern experiment (Hox) |
|
Definition
| Location of gene expression may tell which cells they function in. |
|
|
Term
| Gain of function mutation experiment (Hox) |
|
Definition
| Gain of function of Antennapedia results in replacement of antenna with legs. Gain of function is difficult to interpret because the tissue affected may have nothing to do with the normal function of the gene. |
|
|
Term
| Gene over-expression mutation experiment (Hox) |
|
Definition
| Because gain of function mutations are rare, engineer gain of function gene function. In testing eyeless, express eyeless in different regions. Eyes formed where expressed. |
|
|
Term
| Relation of HOX genes in relation to embryo- |
|
Definition
| Hox genes correlates with their pattern of expression. |
|
|
Term
|
Definition
| descent from common ancestor |
|
|
Term
|
Definition
| result from ancient genome duplications |
|
|
Term
Epithelial tissues cover what in the body?
What do they consist of?
Function? |
|
Definition
Outside of the body and line the surface of organs.
Consist of layers of tightly packed cells.
Forms a barrier between outside environment and inside organism. |
|
|
Term
| What is unique about epithelial tissue? |
|
Definition
| Epithelial tissue has polarity, or a sidedness. Consists of an apical (contacts outside) and basolateral (contacts inside) side. |
|
|
Term
| What prevents leakage between cells? |
|
Definition
|
|
Term
| How can epithelial cells differentiate? |
|
Definition
| Surface/volume ratio. Some have different transport proteins to allow for specific functions. |
|
|
Term
| What is the purpose of Sensor? Integrator? Effector? |
|
Definition
| Record parameter. Compares sensor input with setpoint, then instructs effectors. Changes parameter to return it to set point. |
|
|
Term
|
Definition
Maintaining a constant internal environment in the face of external changes.
Conformation- internal state matches external
Regulation- physiological mechanisms that adjust internal state |
|
|
Term
|
Definition
| Solutes move from high concentration to low concentration depending on membrane permeability. |
|
|
Term
|
Definition
| Water moves from areas of high concentration to low concentration. |
|
|
Term
|
Definition
| Maintenance of a relatively constant physical and chemical environment within an organism. (Water and salt in fish) |
|
|
Term
Isotonic-
Hypertonic solution-
Hypotonic solution- |
|
Definition
[Solute/solvent concentration equal. No change.]
[High solute concentration environment. Net flow of water out of cell; membrane shrinks]
[Low solute concentration outside of cell. New flow water into cell; membrane swells/bursts] |
|
|
Term
Osmoconformers-
Osmoregulators- |
|
Definition
Tissues isotonic
active regulation of osmolarity inside organism to achieve homeostasis |
|
|
Term
| What is needed for active transport? |
|
Definition
| Energy (ATP) to pump against gradient. |
|
|
Term
Cotransporter
Symporter
Antiporter |
|
Definition
| Utilize energy from molecule moving down its concentration gradient to move one against gradient. Symporter moves both molecules in. Antiporter drives molecule against gradient out. |
|
|
Term
| What is the function of the kidney? |
|
Definition
| The kidney is responsible for regulating water and electrolyte balance in terrestrial vertebrates. |
|
|
Term
| What are the parts of the kidney? |
|
Definition
1. Renal corpuscle
2. Proximal tubule
3. loop of henle
4. Distal tubule
5. Collecting duct |
|
|
Term
| What happens in the renal corpuscle? |
|
Definition
| Blood enters the glomerulus and small molecules move through filter into pre-urine, while larger molecules stay in the blood. |
|
|
Term
| What happens in the proximal tubule? |
|
Definition
| Glucose, salt, and water are reabsorbed. 2/3 of salt and water reabsorbed. (active and passive transport) |
|
|
Term
| What happens in the loop of Henle? |
|
Definition
In the descending loop vast majority of water leaves. Occurs because surrounding cells are impermeable to solute and have high solute concentration. Only osmosis.
In the ascending loop of henle vast majority of salt is recovered. First passive, then active transport. Cells are impermeable to water to maintain gradient. Later active transport is necessary. |
|
|
Term
| What occurs in Distal tubule and collecting duct? |
|
Definition
| Water is passively reabsorbed in distal tubule then actively reabsorbed by ADH in collecting duct. |
|
|
Term
| What is the difference between egg and sperm cells in plants and animals? |
|
Definition
| In plants sperm and egg cells are produced from haploid cells via mitosis, not directly from diploid cells by meiosis as in animals. (meiosis->mitosis) |
|
|
Term
| What is the role of pollen grains? |
|
Definition
| Sperm develop from multicellular pollen grains. Pollen grains have a protective coat and are carried to flowers by wind, water, or animals. |
|
|
Term
|
Definition
| When pollen grain interacts with stigma at top of carpel. |
|
|
Term
|
Definition
| Female reproductive structure containing the ovules. |
|
|
Term
|
Definition
| Many flowers are hermaphrodites and evolve incompatibility for its own pollen. |
|
|
Term
| How does double fertilization occur? |
|
Definition
| One sperm nucleus fuses to two maternal nuclei to form triploid cells. One sperm nucleus fuses with egg to form zygote. |
|
|
Term
| Differences between plant and animal development- |
|
Definition
Plant growth and development take place without cell migration, as occurs in animals.
Plant embryonic structures take shape because cell divisions occur in precise orientations and the resulting cells exhibit differential growth.
Nearly all plant organs are formed post-embryonically. |
|
|
Term
| Where are stem cells in plants? |
|
Definition
Shoot apical meristem (SAM)
Root apical meristem (RAM) |
|
|
Term
| What is the role of meristems after embryonic development? |
|
Definition
| Meristems drive further development of the plant body. |
|
|
Term
| When does gametogenesis occur? |
|
Definition
| When a shoot meristem converts from vegetative development to reproductive development. |
|
|
Term
|
Definition
| Enclose and protect the flower |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| What are the 3 central components of the ABC model? |
|
Definition
1. Each of the three genes regulating flowering is involved in the formation of two adjacent whorls.
2. Four different combinations of gene products are possible, each generating a unique signal.
3. These four signals act in the developing flower to specify the four organ types. |
|
|
Term
What are the codes for each organ?
(in the ABC model) |
|
Definition
Sepal-A
Petal-AB
Stamen-BC
Carpel-C |
|
|
Term
| What else to ABC genes do? |
|
Definition
| ABC genes all code for DNA-binding transcription factors. |
|
|
Term
| What is the plant body's function? |
|
Definition
| Harvest diffuse resources (light, water, nutrients) and concentrate them into specific cells. |
|
|
Term
|
Definition
| Evaporation of H20 from plant. |
|
|
Term
| What are the 2 necessary molecules needed for plant to function metabolically? |
|
Definition
|
|
Term
|
Definition
| small openings in the epidermis for gas exchange. |
|
|
Term
| What is the function of a thick waxy coat on the epidermal cells? |
|
Definition
|
|
Term
| How is water transported up stem? |
|
Definition
| Driving force is difference in water potential. A gradient exists between soil, plants, and atmosphere. Plants tend to gain water from the soil and lose it to the atmosphere. ALL PASSIVE TRANSPORT. |
|
|
Term
| Why don't cells explode with incoming water in plants? |
|
Definition
| Cell wall holds structure. (Turgor pressure) |
|
|
Term
| What are the steps of the cohesion tension theory? |
|
Definition
1. Water diffuses from stoma
2. Water evaporates from cell
3. Water is pulled out of xylem
4. Water is pulled up xylem
5. Water is pulled out of root cortex
6. Water is pulled out of soil |
|
|
Term
|
Definition
| Sugars move along their concentration gradients from source to sinks. |
|
|
Term
|
Definition
| specialized cells in vascular system to move sugars. Alive at maturity. Contains Sieve-tubes and companions. |
|
|
Term
| What is the translocation cycle in plants? |
|
Definition
| Only few plant cells produce sugars by photosynthesis. Sugar goes from sources (leaves) to places that use it (roots, flower). Roots can save up sugar and act as sources when needed. |
|
|
Term
| What kind of cells does the Phloem contain? |
|
Definition
| Sieve-tube members (long thin cells that have perforated ends) and companion cells. |
|
|
Term
|
Definition
| Normal plant cell with the function of maintaining the cytoplasm and the plasma membrane of sieve-tube members. Sucrose cotransport into cell and diffuse to sievetube. Hydrogen ions pumped out. |
|
|
Term
|
Definition
| Water conducting cells are hollow tubes (dead at maturity) Secondary cell walls are lignin (vegetable fiber and wood) Water moves vertically through tubes and laterally across pits/perforations. |
|
|
Term
| How does sucrose move throughout phloem? |
|
Definition
1. Sucrose moves from cell to companion cell by active transport (cotransport)
2. Concentration of sucrose in phloem (near leaf source) is higher than adjacent phloem.
3. As water moves in turgor pressure in phloem source increases, driving flow.
4. Cells at the sink remove sucrose- difference in solute concentration between phloem and xylem decreases. |
|
|
Term
|
Definition
| Act on same cell that secretes them. |
|
|
Term
|
Definition
| diffuse locally and act on neighboring cells |
|
|
Term
|
Definition
| are hormones carried between cells by blood or other body fluids |
|
|
Term
|
Definition
| diffuse a short distance between neurons |
|
|
Term
|
Definition
| are released from neurons but act on distant cells |
|
|
Term
|
Definition
| released into the environment and act on a different individual |
|
|
Term
|
Definition
Organic compounds.
Secreted from cells in an endocrine gland (or dispersed in other tissues).
Act on remote target cells.
Present in extremely small concentrations but have large effects. |
|
|
Term
| What is the endocrine pathway? |
|
Definition
| Stimulus->endocrine cell->effector cell->response |
|
|
Term
| What is the neuroendocrine pathway? |
|
Definition
| Stimulus->sensor cell->CNS->effector cell->response |
|
|
Term
| What is the neuroendocrine-to-endocrine pathway? |
|
Definition
| Stimulus->sensor cell->CNS->endocrine cell->effector cell->response |
|
|
Term
| What are the chemical characteristics of polypeptides? |
|
Definition
| Not lipid soluble; bind to receptors on surface of target cell. |
|
|
Term
| What are the chemical characteristics of amino acid derivatives? |
|
Definition
| Most not lipid soluble; bind to receptors on surface of target cell. |
|
|
Term
| What are the chemical characteristics of steroids? |
|
Definition
| Lipid soluble; often bind to receptors inside the target cell. |
|
|
Term
| Corticotropin-releasing hormone(CRH): |
|
Definition
| stimulates release of ACTH from pituitary gland; one of many hypothalamic hormones that regulate release of various pituitary hormones (located in hypothalamus) |
|
|
Term
| Antidiuretic hormone (ADH): |
|
Definition
| promotes reabsorption of H20 by kidneys (located in hypothalamus) |
|
|
Term
|
Definition
| stimulates growth factors in peripheral tissues. regulate cell cycle, cell differentiation, cell survival |
|
|
Term
| Adrenocorticotropic hormone (ACTH) |
|
Definition
| stimulates adrenal glands to secrete glucocorticoids (located in pituitary gland) |
|
|
Term
| Thyroid-stimulating hormone (TSH): |
|
Definition
| stimulates thyroid gland to secrete thyroxin (located in pituitary gland) |
|
|
Term
|
Definition
| Increases metabolic rate and heart rate; promotes growth (located in thyroid) |
|
|
Term
|
Definition
Decreases blood glucose (located in pancreas)
triggers uptake and storage of glucose in response to high blood glucose: glucose stored as glycogen. |
|
|
Term
|
Definition
Increases blood glucose (located in pancreas)
functions in the reverse way when levels of blood glucose are low: glycogen released as glucose. |
|
|
Term
|
Definition
many effects related to short term stress response (located in adrenal glands)
Post transcriptional regulation. |
|
|
Term
|
Definition
| Many effects related to short-term and long-term stress responses (located in adrenal glands) Inhibits CRH release, inhibit ACTH, promote increase in blood glucose, replenishing used glucose. regulate at transcriptional level. |
|
|
Term
|
Definition
| Increases reabsorption of Na by kidneys (located in adrenal glands) |
|
|
Term
|
Definition
| A peptide from the anterior pituitary that stimulates production in peripheral tissues of growth factors (secreted peptides with endocrine, paracrine, & autocrine functions). |
|
|
Term
| What is the function of growth factors? |
|
Definition
| Regulate the cell cycle, cell differentiation and cell survival. |
|
|
Term
| What are gonadal hormones? |
|
Definition
| Steroids produced in gonads such as androgens and estrogens that are regulated by hormones from the pituitary gland. Function on seasonal or cyclic activity. |
|
|
Term
| What are the types and effects of diabetes? |
|
Definition
| Type 1- lack of insulin Type 2- defects in the insulin receptor function results in large volume of urine containing glucose. |
|
|
Term
| What are properties of stress? |
|
Definition
| Adaptive stress response mediated in conjunction with the sympathetic nervous system (part of the sutonomic, peripheral nervous system) Short term (acute) stress response differs from long-term stress response(chronic) Epinephrine from the adrenal medulla triggers the acute response Cortisol from the adrenal cortex mediates recovery after an acute stress and the effects of chronic stress |
|
|
Term
|
Definition
| Constrict pupils stimulate salive slow heartbeat constrict airways stimulate activity of stomach inhibit release of glucose; stimulate gall bladder stimulate activity of intestines |
|
|
Term
|
Definition
| dilate pupils inhibit salivation increase heartbeat relax airways inhibit activity of stomach stimulate release of glucose; inhibit gallbladder inhibit activity of intestine secrete epinephrine and norepinephrine. |
|
|
Term
| What is a major response to epinephrine (metabolically speaking)? |
|
Definition
|
|
Term
| What amplifies epinephrine signal? |
|
Definition
| Cascade of enzyme reactions initiated by cAMP. |
|
|
Term
| How is homeostasis in glucose metabolism restored? |
|
Definition
| Cortisol promotes breakdown of lipids and proteins for glucose synthesis. |
|
|
Term
|
Definition
| 1. Steroid hormone enters target cell 2. Hormone binds to receptor, induces conformational change. 3. Hormone-receptor complex enters nucleus and binds to DNA, induces start of transcription. 4. Many mRNA transcripts are produced, amplifying the signal. 5. Each transcript is translated many times, further amplifying the signal. |
|
|
Term
|
Definition
| Use light energy to produce ATP by photophosphorylation (O2 is electron acceptor) and fix CO2 by the calvin cycle; others split H2S instead of water for photosynthesis. |
|
|
Term
|
Definition
| Oxidize organic molecules with high potential energy to produce ATP bu cellular respiration or fermentation; some fix CO2 by other pathways. |
|
|
Term
|
Definition
| Oxidize inorganic molecules such as ammonia or methane to produce ATP bu cellular respiration; some fix CO2 others use methanol or CO for carbon source. |
|
|
Term
| How do most antibiotics work? |
|
Definition
Most antibiotics are naturally occurring and act as non-competitive or competitive inhibitors
OR poison bacterial enzymes involved in cell wall synthesis or ribosomal enzymes |
|
|
Term
How do the following antibiotics work?
1. Sulfonamides
2. Myxopyronin, rifampicin
3. Tetracycline
4. Penicillin |
|
Definition
1. Folic acid biosynthesis (required for nucleotides)
2. RNA polymerase function (blocks transcription)
3. Ribosome function (blocks translation)
4. Peptidoglycan cell wall synthesis (disrupts cell wall and blocks growth) |
|
|
Term
| How does antibiotic resistance develop? |
|
Definition
| Natural selection drives development of antibiotic resistance when antibiotic use is common. Genetics traits are passed between bacteria encoded on plasmids. |
|
|
Term
|
Definition
| Particles/agents that are obligate parasites. Enter host cell and take over its biosynthetic machinery. |
|
|
Term
|
Definition
| Overlapping reading frames-two proteins are encoded by overlapping segments of DNA read in different frames. Multiple proteins encoded by a single open reading frame: the long polypeptide bust be cut by a different protease to release the different proteins. |
|
|
Term
|
Definition
results in new generation of virus particles and death of host cell.
1. Viral genome enters host cell
2. Viral genome is replicated and transcribed.
3. Viral mRNAs are translated, and proteins processed.
4. Particles assemble inside host.
5. Particles exit to exterior.
6. Free particles in tissue or environment. |
|
|
Term
|
Definition
results in replication in virus genes being transmitted to daughter cells of the host.
1. Viral genome enters host cell
2. Viral genome integrates into host cell genome.
3. Host-cell DNA polymerase copies chromosome.
4. Cell divides. Virus is transmitted to daughter cells. |
|
|
Term
| Retroviruses include what? |
|
Definition
|
|
Term
| What is the process for HIV infection? |
|
Definition
| 1. virion binding to CD4 and chemokine receptor. 2. Fusion of HIV membrane with host cell membrane; entry of viral genome into cytoplasm. 3. HIV RNA genome enters cell. 4. Reverse transcriptase-mediated synthesis of proviral DNA 5. DNA 6. Integration of provirus into host cell genome. 7. cytokine activation of cell; transcription of HIV genome; transport of viral RNAs to cytoplasm. 8. Translation to synthesize HIV proteins 9. Assembly of virioncore structure. 10. Budding and release of mature virion. |
|
|
Term
|
Definition
|
|
Term
| Peripheral nervous system |
|
Definition
| All other parts of the nervous system other than brain and spinal cord |
|
|
Term
|
Definition
| Special cells that wrap their membrane around neuron axons. separated at nodes of Ranvier. |
|
|
Term
| What is the improved process with myelination? |
|
Definition
1. As charge spreads down an axon, myelination prevents ions from leaking out across the plasma membrane.
2. Charge spreads unimpeded until it reaches an unmyelinated section of the axon, called the node of ranvier, which is packed with Na+.
3. In this way, electrical signals continue to jump down the axon much faster than they can move down an unmyelinated cell. |
|
|
Term
| What is the process for release of neurotransmitter? |
|
Definition
1. Action potential arrives; triggers entry of Ca+
2. In response to Ca+, synaptic vesicles fuse with presynaptic membrane, then release neurotransmitter.
3. Ion channels open when neurotransmitter binds; ion flow cause change in postsynaptic cell potential.
4. Ion channels will close as neurotransmitter is broken down or taken back up by presynaptic cell. |
|
|
Term
| Life cycle in multicellular organisms |
|
Definition
Fusion of haploids (gametes) to form diploid
Cleavage
Blastula-Gastrulation>gastrula
organogenesis occurs, followed by growth |
|
|
Term
| Species-specific recognition between sperm and egg in sea urchins |
|
Definition
1. Chemotaxis- egg jelly releases a small peptide that attracts sperm; each species has a distinct peptide
2. Sperm adhesion- sperm binds egg membrane by "lock-and-key" (ligand-receptor interaction)
Adhesive protein on sperm membrain = bindin
Bindins from different sea urchins species are different
Bindin binds to a specific receptor on egg vitelline envelope |
|
|
Term
| Methods to prevent polyspermy |
|
Definition
Wave of Ca2+ from the site of sperm entry
Fertilization envelope lifts and blocks excess sperm:
1. Egg is covered with sperm. One sperm enters.
2. Fertilization envelope begins to lift and clear away excess sperm.
3. Fertilization envelope expands across egg
4. Completed fertilization envelope has cleared all excess sperm off. |
|
|
Term
|
Definition
creating a multicellular organism from the zygote
In plants- zygote undergoes an asymmetric cell division producing a large basal cell and a small apical cell
The asymmetries in the basal and apical cells help establish the apical-basal axis of the plant |
|
|
Term
|
Definition
| in specific locations in oocytes will give rise to specific types of cells |
|
|
Term
| Activating the zygotic genome |
|
Definition
During early cleavage stages (cell cycle =M+S) no RNA transcription occurs
cytoplasmic determinants (maternal contributions of protein, RNA , etc soted in the oocyte) control development
RNA transcription (from the zygotic genome) begins after several cleavages |
|
|
Term
|
Definition
Ectoderm-skin
Mesoderm-muscles, organs
Endoderm- gut |
|
|
Term
|
Definition
end of cleavage, hollow ball of cells, mitotic division slows, zygotic transcription starts
Gastrulation: dramatic cell movements and rearrangements to generate 3 germ layers->some cells move inside |
|
|
Term
|
Definition
| the dorsal lip of the blastophore has the ability to direct embryonic development to generate the entire body plan |
|
|
Term
| The organizer (embryonic development) |
|
Definition
Organizer cell releases signaling molecule
Cell receiving high levels of signal influences which fate it goes to |
|
|
Term
|
Definition
haploid cells
formed in reproductive organs of adult organisms; not necessarily in different individuals |
|
|
Term
| Pollination and fertilization in plants |
|
Definition
pollen binds to carpal and grows towards ovaries due to chemicals from ovary
One sperm fuses with the egg to form the diploid zygote
One sperm fuses with the maternal cell with two haploid nuclei to form a triploid cell in an event known as double fertilization
The triploid cell divides repeatedly to form a nutritive tissue called endosperm. This tissue stores nutrients inside the seed germination, and early seedling growth |
|
|
Term
| Method of embryogenesis in arabidopsis |
|
Definition
1. start with zygote
2. apical basal axis is established by asymmetrical cell division
3. apical and basal cells divide in different planes
4. Radial axis is established in the globular stage
5. Cotyledons and meristems begin to form
6. The embryo continues to grow as cell divisions occur in precise orientations |
|
|
Term
|
Definition
codes for monopteros protein, transcription factor activated by the hormone auxin and required for hypocotyl and root development
Suxin is produced in the shoot apical meristem and transported unidirectionally to the basal parts of the embryo |
|
|
Term
| Organizational principles |
|
Definition
Hierarchy of structure/function: cells, tissues, organs, organ systems
Adaptations to environmental conditions: traits in a species are derived by natural selection from preexisting traits (biology does not create a perfectly engineered solution)
Acclimation: short-term, reversible changes in response to environmental fluctuations
Homeostasis: maintaining relatively constant chemical and physical conditions in the body |
|
|
Term
| 3 steps of urine formation |
|
Definition
filtration of blood -> pre-urine
reabsorption of water, nutrients, and some solutes
regulated removal of additional salt and water |
|
|
Term
| 4 types of tissues in plants: |
|
Definition
1. Meristematic tissue- rapidly dividing, undifferentiated, responsible for continued growth
2. Dermal tissue (epidermis)- single layer of cells covering plant; secretes waxy cuticle (reduces evaporation and barrier against pathogens)
3. Ground tissue- bulk of plant body, complex (several types of cells, many specialized for structural support with a secondary cell wall)
4. Vascular tissue- specialized for long distance transport of water and nutrients |
|
|
Term
|
Definition
in gonads
androgens and estrogens
regulated by hormones from pituitary
seasonal or cyclic activity |
|
|
Term
| How does PHOT1 sense blue light? |
|
Definition
| phosphorylated in presence of blue light |
|
|
Term
|
Definition
| responsible for plant bending to light, hormone |
|
|
Term
| How is the responding cell responsible for phototropism |
|
Definition
1. cells at coleoptile tip sense light
2. hormone travels from the tip down to the stem
3. cells lower in stem respond to hormone. bending results |
|
|
Term
| Signal that causes shoot bending |
|
Definition
|
|
Term
| Why the asymmetric distribution of auxin |
|
Definition
| lateral distribution results from light in tip |
|
|
Term
How can plants with rigid cell walls bend?
(Increasing turgor) |
|
Definition
1. When auxin binds with ABP1, the resulting signal transduction causes an increase in the number of H+ -ATPases (proton pumps) in the membrane.
2. The proton pumps increase the acidity of the cell wall outside the membrane.
3. The acidity of the cell wall causes positively charged ions such as potassium (K+) to enter the cell via channels, and sugars to enter via cotransporters.
4. As the concentration of ions inside the cell increases, water enters by osmosis, causing the turgor of the cell to increase. |
|
|
Term
How can plants with rigid cell walls to bend?
(cell wall expansion) |
|
Definition
1. When auxin binds with ABP1, the resulting signal transduction causes an increase in the number of H+ -ATPases in the membrane.
2. The proton pumps increase the acidity of the cell wall outside the membrane.
3. The acidity of the cell wall causes proteins called expansins to loosen the connections between cellulose microfibrils.
4. Cell elongation occurs and new cellulose microfibrils are produced.
[Increased turgor pressure and cell growth cause cell to elongate, and the loosened cell wall can accommodate this change in shape] |
|
|
Term
| Effect of infrared light on plant |
|
Definition
| grow long and spindly to compete for light |
|
|
Term
|
Definition
| on-off switch for germination, signal day/light |
|
|
Term
|
Definition
stimulate shoot elongation
environmental cues trigger germination
GA from the embryo induces production of enzyme alpha amylase associated with germination |
|
|
Term
| Procedure of gibberellins activate production of a-amylase |
|
Definition
Seed absorbs water, germination begins
gibberellins diffuse from the embryo to the aleurone layer
cells in the aleurone layer respond by releasing digestive enzymes, such as a-amylase
the enzymes digest starch, releasing sugars and other molecules to the growing plant |
|
|
Term
| How gibberellin activates a-amylase |
|
Definition
1. Gibberellin binds to receoptor on plasma membrane of cell in aleurone layer
2. Signal from GA receptor leads to production of Myb protein
3. Myb protein binds to the promoter for a-amylase gene and activates transcription
4. a-amylase is produced and exported into starchy interior of seed. |
|
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Term
| ABA induces seed dormancy (abscisic acid) |
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Definition
in absence of water, ABA increases the expression of transcription factors that inhibit transcription of a-amylase in the seed
Opposite actions of ABA and GA is dormancy v germination
Molecular mechanism of action: hormone binds receptor activating signaling pathways that regulate expression of target genes that code for protein transcription factors that activate or repress transcription of genes required for germination
Also drought stress, closes guard cells in stomata |
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Term
| Stomata procedure to close in response to ABA |
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Definition
1. Pumping of H+ atpases stops. outward directed CL- channels open. Cl- exits along electrochemical gradient.
2. Change in membrane porential opens outward directed K+ channels.
3. H2O follows by osmosis
4. Cells shrink. Pore closes. |
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Term
| Traits shared by bacteria and archaea |
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Definition
No nuclear envelope
cDNA
few/no organelles
most/all unicellular
asexual reproduction |
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Term
| Traits shared by archaea and eukaryotes |
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Definition
DNA associated with histones
Cell wall components do not include peptidoglycan
Complex RNA polymerase
translation begins with methionine |
|
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Term
| Koch's Postulates (germ theory of disease) |
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Definition
Microbe must be present in individual suffering from the disease and not present in healthy individuals
Microbe must be isolated and grown in culture away from host
Microbes from pure culture injected into healthy individual should cause disease
Microbes from experimentally infected individual should be isolated, grown in culture, and demonstrated to be identical to original microbes |
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Term
| What factors have reduced disease mortality rates? |
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Definition
Sanitation
Anti-bacterials |
|
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Term
| Gram differences (cell walls) |
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Definition
Gram stain- highly hydrophobic
Gram positive:
cells stain purple
Gram stain is dye that binds to peptidoglycan cell wall
Penicillin disrupts synthesis of peptidoglycan cell wall
Gram negative:
Gram negative cells are pink, builds a second bilayer membrane and peptidoglycan cell wall is in center of 2 bilayers
Special secretion and transport mechanism needed to build a plasma membrane on the outisde of the peptidoglycan cell wall
Antibiotic erythromyosin (poison bacterial ribosomes) |
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Term
| General mechanisms of immunity |
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Definition
Innate (response to any pathogen)
Aqcuired (response to specific pathogen)
-Immunization to promote acquired immunity
-Vaccination |
|
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Term
|
Definition
Innate: Mast cells, Neutrophils, Macrophages
Acquired: Lymphocytes (T & B cells), Macrophages |
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Term
|
Definition
Skin: most important physical and chemical barrier (skin is dry and acidic)
Mucus: protects lining of digestive, urinary, respiratory and genital tracts |
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Term
|
Definition
1. Bacteria and other pathogens enter wound
2. Platelets from blood release blood-clotting proteins at wound site.
3. Injured tissues and macrophages at the site release chemokines (dilate blood vessels and increase permeability), which recruit immune system cells to site
4. Mast cells at sire secrete factors that constrict blood vessels at wound but dilate blood vessels near wound.
5. Neutrophils arrive, begin removing pathogens by phagocytosis
6. Some newly arrived leukocytes mature into macrophages that phagocytize pathogens and secrete key cell-cell signals |
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Term
|
Definition
| stimulate cell division and induce fever |
|
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Term
| Mechanism for recognition of bacteria by leukocytes |
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Definition
Pattern-recognition receptors on leukocytes recognize foreign molecules
-bacterial proteins begin with N-formylmethionine |
|
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Term
|
Definition
| release chemical signals that constrict blood vessels near wound and histamine that dilates vessels nearby |
|
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Term
|
Definition
| Secrete lysozyme (degrades bacterial cell walls) and reactive oxygen intermediates (H2O2) and phagocytize invading cellular pathogens |
|
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Term
| 3 main types of lymphocytes |
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Definition
B-cells: make antibodies
CD4+ Helper T-cells: activate B cells and CTL
CD8+ Cytotoxic T-cells (CTL): kill infected host cells |
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Term
|
Definition
Formed and mature in primary organs of the immune system: Bone marrow and Thymus
Recognize antigens and become activated in the spleen and lymph nodes
move around in blood vessels and lymphatic ducts |
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Term
|
Definition
1. Antigen is recognized by specific receptor on cell surface
2. Antigen-receptor binding triggers signal transduction pathway = activation
3. Activation: cell division is stimulated and a clone of identical cells is produced; Lymphocytes differentiate to fight the pathogen
4. Some of the lymphocytes persist (and can respond quickly if the same pathogen invades) |
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Term
|
Definition
| Unique and specific receptor that recognizes antigen |
|
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Term
|
Definition
| identical to receptor except they lack the transmembrane domain and are secreted |
|
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Term
| What accounts for diversity and specificity of B and T cell receptors and antibodies? |
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Definition
| DNA recombination between genes that code for constant and variable regions creates a unique hybrid immunoglobin gene in each immature lymphocyte |
|
|
Term
| Gene recombination hypothesis for immunoglobin diversity |
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Definition
immature lymphocytes have a change in genome to make different combination to form different immunoglobin
(involves RNA transcription and processing) |
|
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Term
|
Definition
| dendritic cell-modified macrophages that ingest pathogens; fragments of foreign proteins/carbohydrates= antigens antigens bound by MHC (trafficked to plasma membrane and presents antigen on cell surface) T cell with a specific receptor binds MHC and is activated |
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Term
| Cell mediated cell suicide |
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Definition
| virus infected cells present MHC- antigens and CD8 cytotoxic cells bind the antigen T cell creates holes in the membrane and injects molecules that trigger apoptosis |
|
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Term
|
Definition
| memory B and T cells provide surveillance and increased effectiveness of the immune response |
|
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Term
|
Definition
| hypersensitive reactions to antigens common antigens (allergens) reacted to. Mast cells secrete histamine and other chemicals |
|
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Term
|
Definition
| self selecting antigen receptors contained on lymphocyte, kill before released to body. |
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Term
|
Definition
| convert sensory input to neural signals |
|
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Term
|
Definition
| coded for by frequency of APs |
|
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Term
|
Definition
mechanoreceptors (hair cells) are the sensory receptor cells for hearing. Hair cells are between two sheets or membrane that vibrate.
During pressure from sound membrane attached to stereocilia bend and K+ influx occurs (high level of K+ in mid cochlea channel as opposed to Na+) |
|
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Term
|
Definition
| rods express specific opsin protein which forms a rhodopsin when bound to retinal. Absorption of photon by retinal leads to isomerization. |
|
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Term
|
Definition
| In the dark Na channels are bound to cGMP and are open. Membrane continually depolarized in the dark. |
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Term
| Hyperpolarization from light |
|
Definition
Rhodopsin absorbs a photon
Transducin (G protein) binds GTP and is activated
Phosphodiesterase is activated and hydrolizes cGMP to GMP
Na channels close and the membrane potential becomes hyperpolarized |
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Term
| Action potential triggering muscle contraction |
|
Definition
1. Depolarize, ACh released.
2. ACh binds to receptors on post synaptic cell, triggering depolarization.
3. Action potentials propagate across muscle cell's plasma membrane and into interior of cell via T tubules.
4. Proteins in T tubulues open Ca++ channels in sarcoplasmic reticulum.
5. Ca++ is released from sarcoplasmic reticulum. Sarcomeres contract when troponin and tropomyosin move in response to Ca++ and expose actin binding sites in the thin filaments. |
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Term
|
Definition
|
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Term
|
Definition
| tubes that bring AP deep into muscle to simultaneously activate cells |
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Term
|
Definition
|
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Term
|
Definition
actin and myosin(motor protein)
myosin "walks" actin forward |
|
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Term
|
Definition
ATP binds, head releases
ATP is hydrolized, head pivots, binds new actin subunit
Pi is released, head pivots and moves filament
Repeat |
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