Evolutionary Physiology - Ch. 1 - 8

The process of adding human interpretation to computer-generated genetic comparisons is called

annotation Much of genomic research is carried out by what are called high-throughput methods. The term refers to methods in which computers carry out preocudes and generate results without moment-to-moment human attention or QC. Adding human interpretation is known as annotating.

One unique feature of the icefish is that they

are the only vertebrates that do not have red blood cells as adults.

Which source contributes to the oxygen stores of Australian sea lions?

O2 in the lungs and O2 attached to blood Hb and muscle myoglobin

The altitude limit at which dedicated human climbers can climb without supplemental O2 is about

8000 m

The lowest temperature inhabited by active communities of relatively large temperature conformers is

-1.9 C

A 5 mOsm solution behaves as if it has

0.0005 Avogadro's number of independent dissolved entities per liter. e.g. A 1 Osm solution is defined to be one that behaves osmotically as if it has 1 Avogadro's number of independent dissolved entities per liter. Saying the same thing in another way: a 1 Osm solution has the same osmotic pressure as is exhibited by a 1 M solution of idea nonelectrolyte.

According to the whole-epithelium view of the gill, how does Cl enter the gill membrane of a freshwater teleost fish?

Active countertransport with HCO3

In the summer, a sun-heated lake will tend to have the lowest concentration of dissolved oxygen

At the bottom of the lake

When researched analyzed the DNA of icefish they found that

Beta-gene was gone and the alpha-globin gene was missing parts The relevant DNA in ordinary fish consists of a complete alpha-globin gene separated by an intermediated stretch of DNA from a beta-globin gene. Each globin gene consists of three exons and two introns. In nearly all icefish the entire beta-globin gene, most of the alpha-globin gene and the DNA betweent eh original globin gene have been deleted. The icefish retain only a nonfunctional PSUEDOGENE, a fragment of the alpha-globin gene consisting of exon 3 and a part of the adjacent intron.

What is the difference between bioluminescence and fluorescence?

Bioluminescence is light produced de novo whereas fluorescence utilizes the process of absorbing light and re-emitted at longer wavelengths.

Which of the following is not a probable method of modulating channel or transporter function? Insertion or removal of channels or transporters from the plasma membrane The existence of multiple molecular forms of the same channel or transporter Blocking or permanent disabling of channels or transporters by ligands Control of tissue-level expression of channels or transporters by gene expression

Blocking or permanent disabling of channels or transporters by ligands. Modulation can happen in the following ways: 1. Multiple molecular forms: isozymes are expressed in different tissues because they can exhibit distinct transport, catalytic, and modulation characteristics. 2. Gene expression: e.g. gene for H-K pump is vigorously expressed in the stomach. Gene expression is often regulated in response to an individual's circumstance and is under hormonal control. 3. Noncovalent and covalent modification: analogous to allosteric modulation. e.g. of covalent modification = phosphorylation. 4. Insertion and retrieval: cells often have reserves of membrane channel or transporter proteins held in locations other than the cell membrane.

Which statement regarding oxygen storage ability in Australian sea lions (aged 6 months to adult) is most accurate? By the time they have reached adulthood, sea lions have increased their lung capacity per gram 4-fold By the time they have reached adulthood, sea lions more than double [Hb] per unit of blood volume. By the time they have reached adulthood, the amount of O2 that can be stored per gram of tissue has tripled. By the time they have reached adulthood, their muscle myoglobin has a significantly higher affinity for O2.

By the time they have reached adulthood, the amount of O2 that can be stored per gram of tissue has tripled. Biologists studying seals have discovered that the capacity of a young seal to store O2 undergoes a dramatic developmental change as the animal matures. A weanling seal which is just starting to dive for good is able to store only about half as much O2 that can be stored when it reaches adulthood. Daya shows that the amount of O2 that can be stored per unit of tissue is half as great in a weanling when compared to an adult. The most important factor that limits the O2 stores of weanlings, relative to adults, is that weanlings have very small capacities to store O2 in combination with myoglobin in their msucles. Weanlings have less muscle than adults and far lower concentrations of myoglobin than adult muscles.

During early development in the killifish (8 days old), what is responsible for osmoregulation in seawater?

Chloride cells The chloride cells are responsible for transporting Cl ions out of the body so the tissue fluids do not become overly satly. They express the Na-K pump in abundance.

Which statement regarding conformity and regulation is FALSE: Conformity and regulation are extremes; intermediate responses are more common Conformity costs more energy to maintain than regulation Animals can be both regulators and conformers. Animals frequently show conformity with respect to some characteristics while regulating others

Conformity costs more energy to maintain than regulation IS FALSE

When epinephrine attaches to a _____ the process of _______ results in a formation of a large amount of intracellular _____.

Consider the Gs process... When epinephrine attaches to a GPCR (Gs) the process of AMPLIFICATION (via adenylyl cyclase, cAMP, and PK) results in the formation of a large amount of intracellular GLUCOSE (via PK activation of glycogen phosphorylase).

What is the best description of the immediate process by which glucose is transported across the epithelial membrane of the small intestine?

Cotransport with Na

The major mechanism of epigenetic marking is (are)

DNA methylation and covalent modification of histones

____ is the study of how animals function through all of the successive stages of growth.

Developmental physiology

How does the environment affect growth in children?

Environmental stresses tend to impair growth

Populations of one salmon species differ genetically, and this difference increases as the physical distance between the populations increases. This statement refers to the study of which level of organization?

Evolution

Which statement regarding fish gills best approximates the description of a mechanism: Fish with more gill SA have an advantage in hypoxic water The larger the fish, the larger gill SA must be to support metabolism. Gills evolved as an organ to extract O2 from water Freshwater fish use ATP to pump ions inward across the gill membrane

Freshwater fish use ATP to pump ions inward across the gill membrane MECHANISM

Which receptor protein brings about cascades of membrane proteins involving significant amplification? Enzyme/enzyme linked receptor GPCR Intracellular receptor Ligand-gated channel

GPCR

Which receptor proteins activate enzymes on the cell membrane?

GPCRs and enzyme/enzyme-linked receptors

Which cell-cell junction allow cytoplasmic flow between connected cells? Gap junction Desmosome Septate junction Tight junction

Gap junctions Tight junction - place where cell membranes are so tightly joined there is no intercellular space between them. A ring of tight junctions act as a fence between the apical and basolateral surfaces of a cell membrane. Septate junction - like tight junctions (they are both occluding junctions) but found in invertebrates. They differ from tight junctions in their fine structure but resemble them in their position and in the way they encircle each cell (demarcating apical and basolateral surfaces). Desmosome - junction at which mutually-adhering glycoprotein filmaonts from two adjacent cells intermingle across the space between the cells. Their principal function is believed to be for strength and support of the contacts between cells. Gap junctions - like desmosomes in that they occur at discrete spots but otherwise they're very different in that they form an open pore between cells. These pores are formed by connexins. These are important in cell-cell communication and allow the passage of intracellular signaling agents between cells.

Which observation resulted from the sea urchin gene family analysis? - Genes that code for gap junctions are present - Genes that code for enzymatic synthesis of adrenaline are present. - Genes that encode for P450 detox are unusually numerous - Genes that code for skeleton mineralization are very similar to those found in vertebrates.

Genes that encode for P450 detox are unusually numerous. In the genome of sea urchins, analysis of gene families indicates that: 1) no genes are present that encode for connexins or other gap junction proteins, 2) no genes are present that code for synthesis or use of Epi or melatonin, although genes do exist for other neurotransmitters, 3) genes that code for elements of innate immune response like pathogen-recognition proteins are way more numerous in comparison to other genomes, 4) genes that code for P450 detox are also unusually numerous, 5) in gene families that control skeleton mineralization the genes differ in major ways from those in vertebrates, and 6) many genes are present that were thought to only exist in vertebrates.

Which situation has been shown to demonstrate epigenetic marking? Birds learning the North star Honeybees fed royal jelly to produce a queen Marine molluscs forming thicker shells in the presence of predators Children not reaching their full potential due to lack of nutrients

Honeybees fed royal jelly to produce a queen In honeybees, research has shown that larvae destined to become workers can be redirected to become queens by manipulating DNA methylation in their cells (an example of polyphenic development). In this case, the change of epigenetic marking radically atlers the physiology of an individual; queens have a functioning reproductive system, whereas workers do not, for example. The change of epigenetic makring also alters body size and longevity.

What is a top-down order of study? What is bottom-up order of study?

In the traditional top-down order of study, investigation proceeds from animal function to tissue function then to tissue biochemistry and finally to gene function. Bottom-up is the opposite: investigation proceeds from genes to gene expression then to tissue biochemistry, and finally to tissue and animal function.

An animal is exposed to halogenated aromatic hydrocarbons and, as a result, its levels of P450 enzymes. This is an example of

Inducible enzymes Consitutive enzymes - present at high, and steady, concentrations regardless of conditions Inducible enzymes - present at low levels, if at all, unless their synthesis is activated by inducing agents

What receptor protein interacts with DNA?

Intracellular proteins These are the only class of receptors that are not localized at the cell surface (they are typically in the cytoplasm or the nucleus). After they are activated by their respective ligand they interact with DNA to activate primary-response genes, the products of which might activate other genes. e.g. Estrogen passes through the cell membrane and binds to a specific estrogen-binding intracellular receptor forming a hormone-receptor complex which is a TF and activates specific promoters and enhancers upregulating expression of particular genes.

Which of the following is not a type of gated channel? Phosphorylation-gated Voltage-gated Ligand-gated Ion-gated

Ion-gated

Which statement about facilitated diffusion is true? Energy is used by the proteins in the transport process Solutes transported by this mechanism move across membranes much more slowly than they would if they did not associated with transporter proteins It always occurs in the direction of electrochemical equilibrium It is a form of active transport

It always occurs in the direction of the electrochemical equilibrium There are three defining properties of FD: 1) Always occurs in direction of electrochemical diffusion. It is a form of passive transport and it is why it's called DIFFUSION. 2) Solutes transported by this mechanism move across membranes much faster than they could if they did not associate with transporter proteins. This is why it's called FACILITATED. 3) The mechanism requires solutes ot bind reversibly with binding sites on the transporter proteins. This is why its not a type of simple diffusion

Which technique is not used in a standard DNA microarray? mRNA extraction Fluor-labeled mRNA Hybridization of each mRNA with the DNA spot representing its specific gene Labeling of DNA by reverse transcription

Labeling of DNA by reverse transcription A microarray plate consists of a grid of spots of DNA. In one common type of microarray experiment, a single array is used to carry out a direct comparison of the mRNAs produced by a tissue under different conditions.The mixes of mRNA molecules present under two conditions are extracted and then labeled with a fluor. The fluor labeled preparations are then premitted to hybridize with the microarray. At this step each spot in the microarray potentially becomes labeled. A spot is labeled with mRNA from only one preparation if the gene it represents was being trancribed under one of two conditions.

Which receptor protein changes membrane voltage immediately when activated?

Ligand-gated channels Ligand-gated channels act as receptors and channels and typically allow the flow of inorganic ions through them. They are particularly useful in the transmission of nerve impulses. e.g. Ach receptors can be blocked by alpha-conotoxin in the cone snail, which eliminates the ability of a fish to move its muscles (since the muscle cells are not stimulated) and it becomes paralyzed.

Low _____ diets during postnatal development ____ affect spatial learning in rates

Low protein diets during postnatal development permanently affect spatial learning in rats. Environmental effects during development may arise from programmed responses to the environment or may be forced by chemical or physical necessity. In the case of malnutrition, spatial learning was studied in rats using two devices: a Morris water maze and a radial arm maze. Many studies found that when rats were subjected to a low-protein diet during their postnatal development, they exhibit impaired performance in the water maze, even long after being returned to a normal diet. Thus deficiencies in an animal's nutritional environment during development cause an easily demonstrated deficit in a capacity to learn.

Energy is used by (what channel/transporter) when bringing glucose into the intestinal epithelial cell.

Na-K ATPase This is secondary active transport. This involces the Na-K pump in the basolateral membrane and a Na-glucose cotransporter in the apical membrane. Then glucose could corss the basolateral membrane by simple diffusion through a glucose channel.

What is the developmental relationship between marine periwinkle snails and crabs?

Marine periwinkles develop thicker shells in waters with crabs present The flat periwinkle snail and the blue mussel are marine molluscs that are preyed on by crabs. Research has shown that when these molluscs grow in the presence of these crabs of a period of weeks, they upregulate shell deposition and develop thicker shells than members of the same species that grow without predators being present. To eat the flesh of a mollusc or snail a crab must first crack the molluscs shell with its claws. No direct contact is required between the crabs and molluscs to trigger shell thickening. For example, when shares share the same water with crabs the snail develops shells that are 10% thicker even when the snails and crabs are kept separate; the snails detect that crabs are nearby by use of chemical cues in the water.

What best describes the data in the figure on the back?

Max O2 consumption varied among mice

Which statement regarding white-footed mouse development is true? White-footed mice are born with fur Metabolic rate increases dramatically during the nesting period At birth, white-footed mice have full thermoregulatory capacity The lowest temperature at which isolated individuals can thermoregulate increases after birth

Metabolc rate increases dramatically during the nestling period Individual adult mice can maintain a deep body temp of 37 C when the air temp is below freezing. Individual newborns, however, quickly cool the environment and in a near freezing environment their tissues would cool to near freezing temperatures. As young mice grow and mature during their 3 week long nestling period the peak rate per gram at which they can metabolically generate heat increases dramatically. In addition, they develop fur, and their resistnace to heat loss increases (insulation). The mice therfore become increasingly able to thermoregulate as isolated individuals. By 18 days, a lone youngster can thermoregulate for hours even in freezing air.

What is Km?

Michaelis constant The substrate concentration needed to reach 1/2 Vmax. So a lower Km means a higher affinity for the substrate.

A membrane that is permeable to only Na separates two solutions. The initial solutions are a 1 M solution of K on the left side of the membrane and a 1 M solution of Na on the right side. What will occur?

Na will diffuse to the left side causing a net negative charge on the right side.

Which statement regarding icefish evolution is true? The evolution of antifreeze proteins occurred multiple times during the evolution of icefish. Only icefish share an ancestor that lost the function of globin genes. The loss of functional globin genes occurred multiple times during the evolution of icefish. Only icefish share an ancestor containing genes that code for antifreeze proteins.

Only icefish share an ancestor that lost the function of the globin genes

Which is the most accurate description of the mech. of the light-emitting reaction in the firefly: NO reacts with luciferyl-AMP to produce light NO reacts with luciferin to produce light Oxygen reacts with luciferin to produce light Oxygen reacts with luciferyl-AMP to produce light

Oxy reacts with luciferyl-AMP to produce light.

In a bioluminescent animal such as the hydromedusa jellyfish, Aequorea Victoria, the ______ consists of luciferin, O2 and a protein.

Photoprotein

What statement regarding physiology is false? Physio is a key discipline for understanding health and disease of nonhuman animals Physio is a key discipline for understanding fundamental bio of all animals. Physio is a key discipline for understanding the social context of disease Physiologists study how animals work

Physio is a key discipline for understanding the social context of disease

______ is a phenomenon in which genetically identical individuals can assume two or more distinctive body forms, induced by differences in the environment.

Polyphenic development Polyphenic development is aphenomenon in which genetically identical individuals can assume two or more distinct body forms induced by differences in environment. The body forms a polyphenic species can be so dramatically differetn that anyone but a specialist would think they represent different species; for example, western white butterflies can express two different pehenotypes. Polyphenic development is the among the most dramatic cases of phenotypic plasticity. Phenotypic plasticity is the capacity for an individual of a fixed genotype to exhibit two or more genetically controlled phenotypes. Because the phenotype expressed is often dependent on the prevailing environment, phenotypic plasticity is a process by which genotype and environment interact to determine the phenotypic characteristics of an individual.

Which of the following is NOT involved at the cell membrane in a second messenger cascade? Adenylyl cyclase Phospholipase C Protein kinase GPCR

Protein kinase At the surface of Gq receptors (forms DAG and IP3) activation of PLC produces DAG and IP3 from PIP2 At the surface, Gs receptors increase cAMP via the activation of cAMP which then, in the cytoplasm, binds to cAMP-dep. protein kinase which activates glycogen phosphorylase and permits glycogen to be broken down into glucose.

What is RNAi?

RNA interference Process that silences protein synthesis and can be manipulated to gain insight into gene function. When certain types of short RNA molecules are introduced into cells and operate in tandem with so-called Argonaute proteins in the RNAi pathway, specific mRNA molecules that are naturally produced by the cells are destroyed or blocked from being translated. In effec, the genes that produce the targeted mRNAs are silenced because the mRNAs produced by transcription of these genes are rendered inoperative lead to protein synth. Essentially, certain proteins are not produced which can give an insight into their function through a potential loss of function.

Which of the following is not a type of membrane protein? Resistance Enzyme Structural Receptor

Resistance

The Dutch Hunger Winter study correlated _____ with subsequent _______.

The Dutch Hunger correlated malnutrition with subsequent epigenetic marking. Researchers discovered that there is a statistically strong tendency for the individuals who were conceived during the famine to exhibit a lower percentage of makred DNA sites than their sibling controles. Reason exists to expect that the reduction in DNA methylations marks induced by famine are allowing greater expression of some genes in adults alive during the Hunger Winter.

Which statement regarding brain phospholipids in fish is most accurate? - The degree of phospholipid saturation in brain synaptic membranes is independent of habitat temp. - The colder the habitat, the greater the degree of phospholipid unsaturation in the brain synaptic membranes. - Fish in very cold habitats tend to have very saturated phospholipids in their brain synaptic membranes. - Tropical fish tend to have very unsaturated phospholipids in their brain synaptic membranes.

The colder the habitat, the greater the degree of phospholipid unsaturation in the brain synaptic membranes. Temperature affects the fluidity of membranes; when they are chilled, the leaflets in phospholipid membranes become more stiff. Unsaturation allows the hydrocarbon tail to bend more readily (more fluid). So, at lower temperatures there is a greater prevalance of unsaturation in phospholipid membranes.

A membrane that is permeable to Na and K separates two solutions. The initial solutions are a 1 M K solution on the left side and a 1 M Na solution on the right side. What will occur?

The movement of Na will be balanced by the movement of K; therefore, there will be no net charge difference.

According to the Fick equation, what happens to J when X (the distance between the two concentrations) is increased?

The net rate of diffusion decreases The Fick equation is: J = D * (C1 - C2)/ X C1 = region of low conc C2 = region of high conc X = distance separating those regions D = diffusion coefficient J = net rate of diffusion

Which of the following is an example of a possible physiological effect a river dam could impose on migrating Pacific salmon?

The salmon may get past the dam, but their effots could cost them too much energy

Which statement regarding proteomics is false: It is the branch of study of the biochemical phenotype It is the study of proteins synthesized by cells and tissues A reason for the study for of proteomics is that the proteins coded by many genes is unknown. The study of proteomics is based on the assumption that protein concentrations can be correlated to mRNA synthesis.

The study of proteomics is based on the assumption that protein concentrations can be correlated to mRNA synthesis. Even if the proteins coded by mRNAs are known and the mRNAs have been quantified protein concentrations cannot necessarily be predicted because protein synthesis is only loosely correlated with mRNA synth. Commonly used technique in proteomics is 2D gel electrophoresis.

Which statement regarding fish eyes and octopus is most accurate? They differ in gross appearance, functional performance, and adaptive significance but are similar in mechanism. They are similar in gross appearance, functional performance, and adaptive significance but differ in mechanism They are similar in all of the above They are similar in gross app. and performance but differ in mech and adaptive significance.

They are similar in gross appearance, functional performance, and adaptive significance but they differ in their mechanisms.

What statement about icefish is true: They have only the two beta-globin subunits in their Hb They have four subunits of alpha-globin They have no red blood cells but do have circulating Hb They do not Hb

They do not have Hb Remember, they have no beta-globin gene and only have pseudogene for alpha-globin.

Which cue is responsible for producing the two phenotypes in western white butterflies?

This is a case of seasonal polyphenism and polyphenic development. Day length and temperature during development often serve as cues that help determine which body form an animal will assume. Two hormones: juvenile hormone and ecdysone, and the timing of their secretions relative to endogenously timed sensitive periods, are frequently implicated in the control of seasonal polyphenism. In these butterflies, an indicidiaul requires a high thoracic temperature to fly; if the thorax is cool, the flight muscles cannot develop sufficient power.

The catalytic effectiveness of an enzyme molecule is expressed as the

Turnover number (k cat) The number of susbtrate molecules converted to product per second by each enzyme molecule when saturated. This depends party on the activation energy as well.

In the most common protein-degradation mech., tagging occurs by the attachment of ____ to the protein targeted to be degraded.

Ubiquitin

What is the proposed advantage to locusts adopted the gregarious phenotype?

When solitary locusts experience crowding they change within a few hours to a gregarious phenotype. The adaptive advantage is postulated that the fast-moving voracious swarms enables locusts to collect large quantities of food.

A comparison of the proteins produced in an animal's muscle tissue before and after exercise is an example of

a screening study In screening, or profiling, one compares a tissue of interest vefore and after a change of interest. So, here the tissue of interest is animal muscle and the change of interest is exercise.

The surprise of a phone call at 3 am results in an increase in heart rate. This is an example of an

acute change

The physiology of very young animals _____ differs from that of adults.

always

Multiple-enzyme sequences in which each enzyme in a sequence activates another enzyme is an example of

amplification A multi-enzyme sequence allows a tiny quantity of signaling compound to have a far greater effect than in would normally have

The hearts of icefish

can have myoglobin or not, depending on the species. Six species of icefish have cream-colored hearts because they lack ventricular myoglobin. The loss of Hb and myoglobin have different paths. Blood Hb was lost when a large stretch of DNA was deleted eliminating one globin gene and rendering the other nonfunctional and this deletion was passed on. By contrast, most icefish syntesize myoglobin in their heart muscle. After the icefish first appeared, mutations that eliminated myoglobin occurred indepently in four of the lines of icefish evolution and today 6 of 16 species of icefish have myoglobin-free ventricular muscle.

Color change in fish depends on flattened pigment-containing cells called

chromatophores chromatophores - permit rapid color change (for survival purposes); these are flattened pigment-containing cells in the skin. In an animal there may be multiple types of chromatophores to permit the change of different colors. The pigment in a chromatophore is in the form of pigment granules each 0.3-1.0 microns in diameter. Color change is accomplished by dispersing (visible) or aggregated (invisible) these granules to produce the desired effect. photocytes - cells that permit bioluminescence. photoprotein - a complex of luciferin, O2 and an inactive form of luciferase.

An arctic fox growing a thicker fur layer in the winter is an example of a(n): evolutionary change chronic change acute change developmental change

chronic change let's delineate the different types here: acute changes - short-term changes that animals exhibit soon after environments have changed. chronic changes - long-term changes that display after environmental changes have been endured for days, weeks, months. evolutionary changes - changes that occur by alteration of gene frequencies over the course of multiple generations in populations exposed to new enviornments. developmental changes - changes that are programmed as an animal matures periodic changes - changes that occur in repeating patterns (e.g. sleep cycle) under the control of internal clocks

If an animal permits internal and external conditions to be equal, it is said to show

conformity

Boundary layers tend to

decrease the net rate of diffusion Outward diffusion of a oslute creates a layer of solute termed the boundary layer. As far as the Fick equation the boundary layer creates an increase in distance between the two regions of solutes (X increases) and also decreases the rate of diffusion. Overall, it decreases the net rate of diffusion. Increasing flow decreases the ability for a boundary layer to form and maximizes diffusion.

Variation in max O2 consumption rate among human populations is

due to both genetic and nongenetic causes

The proton pump in the stomach is an example of a(n) _______ pump.

electroneutral

When all of the epigenetic marks in a cell or tissue are described together as a set, this global summary of marks is termed the

epigenome The set of all methylated sites is termed the methylome

A change of gene frequencies over time in a population is referred to as

evolution

The overarching goal of genomics is to elucidate the ______ of genes and genomes.

evolution and current function In the study of the evolution of genes and genomes, one central topic is the elucidation of mechanisms of gene function. For example, one mechanisms elucidated by genomics is that genes sometimes become modified during evolution by the accumulation of mutations favored by natural selection. Because genes found in one a new genome may be similar to others in another genome, the function of genes can be predicted via extrapolation. This brings up the principle that homologous genes in different species often have similar functional properties.

The example of killifish allele frequency distribution along the Atlantic coast describes enzyme changes of a(n) _______ time frame.

evolutionary Focusing on the evolution of allele frequency within single species is meant to highlight evolution in action. Changes in allele frequencies can be highly dynamic and occur on short-time scales. Killifish living in Georgia experience temperatures that are 15 C higher than their counterparts in Maine. In killifish there are two major alleles of the B form of lactate dehydrogenase (LDH). The Georgian killifish mainly have the a allele where the Maine killifish have the b allele. Essentially, the allele frequency of the a allele becomes less frequent from Georgia to maine.

In some forms of epigenetic modification, when a gene is "marked" its: genetic code is temporarily modified expression is semi-permanently altered genetic code is permanently modified expression is permanently altered

expression is semi-permanently altered

Compared to rats, humans have

faster brain development relative to their reproductive age.

When an allosterically-modulated enzyme is the rate-limiting enzyme in a metabolic pathway, the entire pathway may be upregulated or downregulated by allosteric modulation. The result of downregulation of an entire pathway is called

feedback inhibtion aka end-product inhibtion; common in metabolic pathways.

The set of genes that can encode for vertebrate globin proteins can bee termed

gene family Various globin genes in a single vertebrate species bear a family resemblance and the globin genes in different species also do - all being related through evolutionary descent. The property that defines a gene family is that all the genes in a family share distinctive DNA base sequences. All the genes in a fmaily also tend to code for functionally similar proteins.

An experimental manipulation in which animals come to lack functional copies of a gene is called

gene knockout

The process of chance assuming the preeminent role in altering gene frequencies is called

genetic drift

The blood plasma of a freshwater teleost fish is _____ relative to the pond water in which it lives.

hyperosmotic

The number of species of swallowtail butterflies tends to increase at ____ and decrease at _____

increase at low latitudes and decrease at high latitudes The reason for this may be twofold: 1) lower temperatures at high latitudes 2) a decrease in diversrity of plants (and other temperature-conforming animals) toward the poles. Conditions are more demanding at the poles, essentially.

Compared to red-blooded fish of the same size, icefish have

larger hearts and higher circulation rates Dramatic morphological and physiological specializations of icefish provide the most compelling evidence that the loss of blood Hb was a disadvantage. Compared with related red-blooded fish of the same body size, existing icefish have very large hearts, and they circulate blood at rates that are far higher than usual. These epcializations strongly suggest that the original loss of blood Hb was a defect that significantly decreased the ability of the circulatory system to transport O2 and the circulatory system tehereafter became modified to make up for the defect by evolving a capacity to circulate the blood exceptionally rapidly.

The study of all the organic compounds in cells and tissues other than macromolecules coded by the genome is called

metabolomics Metabolomics does not focus on gene products (like proteomics). The compounds encompassed include molecules of low MW including sugars, AAs and FAs. Most of these molecules are metabolites and their study is meant to clarifoy the metabolic pathways operative in cells and consider the way they are modulated.

In one study, researchers found that after 4-8 hours of exercise the mRNAs of _____ genes were found to have increased.

mitochondrial enzyme There are stress-response genes that quickly exhibit enhanced transcription during and after exercise. Metabolic priority genes are slower to be upregulated but also exhibit a dramatic increase in transcription. Mitochondrial/metabolic genes are slowest to be upregulated and only exhibits modest, but long-term, increases in transcription.

Epigenetics refers to

modifications of gene expression (with no change in DNA sequence) that are transmitted when genes replicate. Gene expression differences are also transmitted upon replications, along with the genes when epigenetic effects are at work. Example: A DNA sequence has been methylated in response to an environmental agent. The methylation is replicated in daughter cells during mitosis.

The increase in frequency of genes that produce phenotypes that raise the likelihood that an animal will survive and reproduce is called

natural selection

Testosterone is released by testes in response to LH. As circulating test rises, it acts on the pit gland to reduce LH secretion thus reducing the production of test. This is an example of

negative feedback

The allosteric site is located

on the enzyme

The passive transport of water across a membrane is called

osmosis Osmosis is the pasasive transport of water across a membrane which can be a cell membrane, an epithelium, or an artificial membrane. Sometimes osmosis is referred to as "diffusion of water".

The ability of an animal (with a fixed genotype) to express two or more genetically controlled phenotypes is called

phenotypic plasticity

Electrical charges on molecules ______ diffusion across a membrane.

play a large role in

For terrestrial animals, one of the greatest physiological challenges is

preventing water loss When vertebrates and invertebrates invaded land from freshwater they began to dehydrate rapidly due to evaporation. When anmals first invaded terrestrial habittates they probably possessed integuements inherited from aquatic ancestors that provided little, or no, barrier from evaporative water loss.

When there are more substrate molecules than enzyme molecules can accommodate, the reaction is

saturated

Length of gestation ____ body size in mammals

scales as an exponential function of

Human LDH-A4 and rat LDH-A4 together are good examples of isozymes OR interspecific enzyme homologs?

sinterspecific enzyme homologs Isozymes are differnet molecular forms of an enzyme produced by a single species whereas interspecific enzyme homologs are the different molecular forms of an enzyme coded by homologous gene loci in different species. Functionally, isozymes and IEHs often differ not only in their catalytic properties but also in their regulatory properties.

Genome sequencing is a technique in which

the DNA sequence of the entire genome of a species is determined

Icefish were once commonly called "bloodless fish" because

the fact that their blood is clear

The study of which genes are being transcribed to make mRNA and the rates at which they are transcribed is called

transcriptomics aka. transcription profiling