Final Exam

Question 1

Conformer (Exam 1)

Answer 1

an animal whose internal conditions match the external environment

Question 2

Homeostasis (Exam 1)

Answer 2

Regulation of the internal environment to maintain stability

Question 3

Hormone (Exam 1)

Answer 3

are secreted by the endocrine system. They are involved in regulating stress, metabolism, growth, reproduction, etc.

Question 4

Negative Feedback (Exam 1)

Answer 4

The regulatory process that helps maintain the levels of some product by functioning to cycle back and essentially shut down a stimulus upstream.

Question 5

Acclimation/Acclimatization (Exam 1)

Answer 5

Types of phenotypic plasticity associated with the chronic physiological timescale. The only difference between them is that acclimation is phenotypic plasticity occurring in a more controlled/lab setting and acclimatization occurs in nature/wild settings

Question 6

The term “______” refers to the physiological components of animals that enable them to perform as they do. (Exam 1)

Answer 6

mechanism

Question 7

Assuming the relationship depicted above is isometric, you can likely infer that the type of units being compared are the following (Hint: think about the dimensions being compared) (Exam 1)

Answer 7

y=mass
x length

Question 8

Given the graph above, what feature would indicate a positively allometric relationship? (Exam 1)

Answer 8

b>2.98

Question 9

A change in a synapse that would be categorized as synaptic plasticity includes: ______ (Exam 1)

Answer 9

long-term potentiation

Question 10

Sweating in response to heat is an example of a(n) (Exam 1)

Answer 10

acute change

Question 11

The electrochemical ion gradient, differential permeability to different ions, and the operation of sodium-potassium ATPase pumps together determine… (Exam 1)

Answer 11

the resting membrane potential

Question 12

______ channels are responsible for the brief period of hyperpolarization at the end of an action potential (Exam 1)

Answer 12

voltage-gated potassium

Question 13

The iodothyronines include hormones such as (Exam 1)

Answer 13

thyroxine

Question 14

In a chemical synapse, the main component responsible for transmission of an impulse from presynaptic to postsynaptic cell is _____ (Exam 1)

Answer 14

any generic excitatory neurotransmitter

Question 15

Which of the following could NOT be the postsynaptic membrane mechanism during an inhibitory postsynaptic potential? (Exam 1)

Answer 15

Increase in the permeability to Na+

Question 16

In a neuromuscular junction, which ion enters the axon terminal in response to a presynaptic action potential? (Exam 1)

Answer 16

Ca2+

Question 17

The glial cells forming myelin sheaths in the CNS are ________ (Exam 1)

Answer 17

Oligodendrocytes

Question 18

Receptors for steroid hormones are typically found _______ because these hormones are _______ (Exam 1)

Answer 18

inside cells; lipid soluble

Question 19

The time period during which a second action potential cannot be generated at a location on a cell membrane is referred to as the… (Exam 1)

Answer 19

absolute refractory period

Question 20

Inhibitory post-synaptic potentials can be caused by the influx of which ion? (Exam 1)

Answer 20

chloride

Question 21

Physiology is an integrative discipline. What does this mean? Explain how a physiologist must be an integrative biologist. What are the important considerations one must make when attempting a study of animal physiology? Pose a potential research question aimed at understanding animal physiology and explain how and which different biological subdisciplines would be used to answer the question. (Exam 1)

Answer 21

It means that not only does physiology integrate multiple disciplines (Bio, Chem, Physics, Ecology, Evolution), but it also integrated all levels of biological organization. When studying animal physiology it is important to acknowledge the levels of organizations you are interested in as well as the other scientific disciplines that will aid in answering the proposed question.
Q: How do different habitat types impact metabolic function?
For this question, it may be important to understand biology and chemistry as they work hand in hand to accomplish metabolic functions.

Question 22

Synaptic plasticity is involved in the development of long-term memory and learning. Describe what we mean when we say synaptic plasticity, explain with examples the different ways that synaptic plasticity occurs, and describe two mechanisms through which synaptic plasticity operates. (Exam 1)

Answer 22

Synaptic plasticity describes when synaptic properties change with time and activity.

In sea slugs forms of learning, like habituation and sensitization were explored, showing real-life examples of synaptic plasticity.

Two mechanisms in which synaptic plasticity operates:
Presynaptically: changes in the rate of NT synthesis, storage, and release
Postsynaptically: sensitivity to NT can be increased or decreased under different circumstances

Question 23

Physiological changes to the external environment occur over varying timescales. Compare and contrast each. Provide an example that demonstrates changes across different time frames. (Exam 1)

Answer 23

Acute: Immediate response (smallest scale)
Ex: sweating in response to heat

Chronic: Physiological changes occur after a longer time period (days, weeks, seasons); acclimation/acclimatization
Ex: an animal’s body insulation changes

Both chronic and acute are reversible and can affect individuals

Evolutionary: Associated with adaptations that come about usually via natural selection (largest scale). It is irreversible and rather than affecting individuals it affects populations over generations
Ex: Bird beak size

Question 24

We know that temperature and body size influence virtually all physiological functions. Explain how scientists study physiological function as it relates to body size. Include in your answer a discussion of how they study allometry. (Exam 1)

Answer 24

Body size and scaling are considered when studying physiology because more often than not there is a (+) relationship between the two. Allometry allows us to view proportional relationships. If a relation is isometric then we know that growth is 1:1 and proportions are constant. This means during development dimensions will scale up and down with each other. in allometric growth, organism proportions change in with body size and depend on SA, V, and other physical parameters. The allometric equation (Y=aX^b) gives us insight into the scales exponent (b) when plotted and derived. This can give us insight into proportions and growth rates.
b>1 (not always 1): growth is (+) allometric (Y increases faster than X)
b< 1( not always 1): growth is (-) allometric (X increases faster than Y)
b=1 (not always 1): growth is isometric
Scaling is important when studying physiological function because it refers to the structural and functional consequences that come with changes in body size in otherwise similar organisms.

Question 25

We know that unmyelinated axons conduct action potentials without decrement. However, some known diseases cause demyelination (the breakdown of myelin sheaths). When this happens, the conduction of action potentials is severely inhibited. Why do you think conduction is inhibited in these cases? Here I want you to speculate on the mechanism. Once you have identified the mechanism, speculate on the potential effects of such a demyelinating disease. (Exam 1)

Answer 25

The conductivity of APs is very dependent on myelination. Myelination is important in preventing ion leakage, insulation, and enhancing AP conductivity speed. The presence of myelin sheaths around axons also allows for saltatory conductivity, meaning the AP can jump from node to node. Myelin sheaths allow APs to travel further and faster. Without myelination, the conductivity of the AP is greatly diminished so APs may not be able to get to the next target. AP responses diminish with increased distance from the stimulation due to leaky channels. Leaky channels are not present in sheath areas so the AP occurs over longer distances. Conduction is inhibited in unmyelinated axons due to the presence of more leaky channels, counteracting the membrane potential. Diseases, like MS, in which myelination is diminished, will eventually cause neuronal function to diminish. This can cause physical movement ability to decrease, making a person wheelchair-bound. It will also cause NT signals to not be transmitted efficiently.

Question 26

Osmoconformer (Exam 2)

Answer 26

an aquatic animal that allows its blood osmotic pressure to match and vary with the environmental osmotic pressure

Question 27

Sarcomere (Exam 2)

Answer 27

are composed of contractile proteins (myosin & actin) which are responsible for muscle contraction. The arrangement of these proteins gives a striated appearance in skeletal muscle.

Question 28

Cooperativity (Exam 2)

Answer 28

a behavior that occurs in protein molecules. The binding site of any one site to its ligand may facilitate or inhibit the binding of other sites on the same molecule to their ligands.

Question 29

Sliding Filament Theory (Exam 2)

Answer 29

is the force of generation caused by the cross-bridges of thick filaments attaching to thin filaments & actively pulling them toward the center of the sarcomere.

Question 30

Tidal Ventilation (Exam 2)

Answer 30

is when air from the environment flows into a passageway (ex. lungs) and mixes with stale air. Oxygen then diffuses into the blood.

Question 31

In the body, water is found in the largest quantity in the... (Exam 2)

Answer 31

intracellular fluid

Question 32

Which of the following scenarios will result in dissolved gas coming out of solution? (Exam 2)

Answer 32

1. Collecting cold creek water, sealing the container, and allowing the solution to warm. 3. Collecting cold creek water, adding salt, sealing the container, and allowing the solution to warm. 4. Collecting cold creek water, adding salt, sealing the container, and keeping the solution at the original temperature

Question 33

_____ is the law that relates partial pressure and concentration in aqueous solutions. (Exam 2)

Answer 33

Henry's Law

Question 34

Cutaneous water loss is primarily dependent on the permeability of the skin and _______ (Exam 2)

Answer 34

difference in vapor pressure inside and outside the body.

Question 35

The blood of a freshwater teleost fish is ______ with respect to ambient conditions. (Exam 2)

Answer 35

hyperosmotic

Question 36

A vertebrate motor unit consists of... (Exam 2)

Answer 36

a single motor neuron and all of the muscle fibers that it innervates.

Question 37

The diagram is referring to what physiological process? (Exam 2)

Answer 37

Cross-current gas exchange

Question 38

At letter A in the diagram, O2 partial pressures are ______ the corresponding medium values and _____ from left to right (Exam 2)

Answer 38

lower than; decrease

Question 39

Which of the following animals is likely to have the highest O2 and CO2 exchange percentage via the skin? (Exam 2)

Answer 39

Lungless Salamander

Question 40

Which of the following denotes the correct sequence of blood movement through the human heart? (Exam 2)

Answer 40

Systemic vein ---> right atrium ---> right ventricle ---> pulmonary artery ---> pulmonary vein ---> left atrium ---> left ventricle ---> aorta

Question 41

A muscle can produce maximal tension when it... (Exam 2)

Answer 41

starts from resting (intermediate) length

Question 42

Variation among species in the height of an oxygen equilibrium curve generally is a consequence of ________ (Exam 2)

Answer 42

differences in the quantity of respiratory pigment per unit blood volume.

Question 43

Diffusion of gases is dependent on ____ (Exam 2)

Answer 43

the difference in gas partial pressure

Question 44

The O2 partial pressure at which the blood is 50% saturated with O2 is known as the ______ (Exam 2)

Answer 44

O2 affinity

Question 45

Myoglobin has a higher oxygen affinity than hemoglobin. True or False (Exam 2)

Answer 45

True

Question 46

Relative to body size, respiratory surface area is greatest in... (Exam 2)

Answer 46

endotherms

Question 47

_______________ is the achievement of maximal muscle tension without muscle shortening (Exam 2)

Answer 47

Isometric contraction

Question 48

An ionic U/P ratio that is greater than 1 indicates that the urine contains _____ sodium compared to the plasma. (Exam 2)

Answer 48

more

Question 49

The surface area of the gas exchange membrane in birds is ______ than in amphibians (Exam 2)

Answer 49

larger

Question 50

Which biochemical mechanisms provide the majority of the ATP for short duration, powerful activities? (Exam 2)

Answer 50

Glycolysis and phosphogen

Question 51

Gases are exchanged in the fish gill via a process called _________ (Exam 2)

Answer 51

counter-current

Question 52

The shape of O2 equilibrium curves among species are different because ________________ (Exam 2)

Answer 52

of different protein globins present

Question 53

Briefly explain the Bohr Effect and its significance. (Exam 2)

Answer 53

The Bohr Effect describes the relationship between pH & oxygen affinity & temperature & oxygen affinity. As pH increases, oxygen affinity increases. As pH decreases, oxygen affinity decreases. As temperature increases, oxygen affinity decreases & vice versa. When there is a high P50 you have low oxygen affinity & vice versa. P50 is the point where 50% of oxygen is saturated. The Bohr Effect is a right shift in the curve. It's significant when thinking about oxygen being picked up and released so it can be used for exercise & distribution through tissues.

Question 54

In a series of short statements, describe the excitation-contraction coupling process. (Exam 2)

Answer 54

An action potential causes Ach to enter the synaptic cleft from the presynaptic neuron and bind to a ligand-gated channel on the muscle. The channel opens & Na+ flows in the cell. This causes depolarization of the T tubules & the DHPR. The DHPR has a conformational change & the RyR Ca2+ channel opens, Ca2+ flows out & binds to troponin which causes tropomyosin to move & expose the myosin binding site & then myosin binds & starts contracting the muscle. Ach then needs to leave the synapse so AchE hydrolyzes it & choline is brought back into the cell to be used again.

Question 55

Compare & contrast co-current & counter-current gas exchange. Include in your answer a discussion of changes in O2 partial pressure in the blood & external medium.

Answer 55

Counter-current exchange is where media (air) & blood flow in the opposite direction. The air has a greater O2 partial pressure than the blood & oxygen flows from high to low PO2. The flow in opposite direction "allows oxygen to be distributed more evenly throughout the blood". Counter-current is more efficient than co-current exchange Co-current exchange is where blood & media (air) flow in the same direction which then makes it to where they reach equilibrium. Both exchanges are unidirectional & both exchanges work well for the organisms that have them

Question 56

Compare & contrast osmoregulation in freshwater & marine teleost fish. (Exam 2)

Answer 56

Freshwater teleost fish are hyperosmotic. They have active uptake of salt through their gills. They lose salt by diffusion through their gills. Marine teleost fish are hyposmotic. They have an active loss of salt through their gills. They gain salt by diffusion through their gills. Both secrete salt through their feces & intake salt from food.

Question 57

Briefly explain adaptations & physiological changes that take place during extended dives in diving mammals. (Exam 2)

Answer 57

The first adaptation is the collapse of the lung (thorax is highly compressible). If the lung wasn't compressible, the mammal wouldn't be able to dive because of buoyancy. The second adaptation or physiological change is bradycardia which is a decline in heart rate. The third adaptation is peripheral vasoconstriction which only allows blood flow to vital organs like the brain, lungs, and heart.

Question 58

2nd law of thermodynamics (Exam 3)

Answer 58

if an isolated system undergoes an internal change, the direction of that change always goes towards disorder.

Question 59

Thermal performance breadth (Exam 3)

Answer 59

the range at which organisms perform well as temperature as temperature increases. The range is in between CTmin & CTmax

Question 60

Indirect calorimetry (Exam 3)

Answer 60

is a measurement of metabolic rates by quantifying respiratory gas exchange or some other property besides heat and external work.

Question 61

Aerobic scope (Exam 3)

Answer 61

is the difference between maximal metabolic rate & basal metabolic rate

Question 62

Maximal aerobic speed (Exam 3)

Answer 62

is the speed at which VO2 (max) is reached. An organism can go the greatest possible distance with the least amount of energy used

Question 63

In mammals, the length of the loop of henle in nephrons is correlated with the... (Exam 3)

Answer 63

thickness of the renal medulla

Question 64

In mammals, the nonurea solutes are trapped in the collecting duct because the... (Exam 3)

Answer 64

collecting duct is impermeable to nonurea solutes but permeable to water.

Question 65

In mammals, the medullary interstitial fluid is _____ to the fluid in the collecting duct (Exam 3)

Answer 65

hyperosmotic

Question 66

During active transport NaCl in the ascending limb of the loop of Henle, the concentration of NaCl in inside the tubule... (Exam 3)

Answer 66

decreases

Question 67

Animals need energy to... (Exam 3)

Answer 67

create & maintain internal organization maintain ion gradients pump blood

Question 68

Suppose an animal is oxidizing food according to the following reaction: C16H32O2 + 23 O2 --> 16 CO2 + 6 H2) + 10,042 kJ/mol. what's the respiratory quotient? (Exam 3)

Answer 68

16/23

Question 69

Which of the following is a factor that exerts a particularly large effect on metabolic rates?

Answer 69

Environmental temperature

Question 70

A measure of thermal tolerance. The body temperature where animals can no longer remove themselves from stressful conditions

Answer 70

CTmax

Question 71

Mechanism of heat exchange via contact with a surface.

Answer 71

Conduction

Question 72

An increase in endurance can be attained via conditioning. A primary mechanism facilitating this increase is

Answer 72

a change in aerobic enzyme production

Question 73

Mechanism of heat exchange associated with movement of the external medium

Answer 73

convection

Question 74

mass-specific metabolic rate is expected to be greatest in

Answer 74

birds

Question 75

if the basal metabolic rate was proportional to the mass of metabolically important organs (e.g. liver) then the scaling exponent would equal

Answer 75

1

Question 76

the primary site of filtration in the nephron is in the

Answer 76

glomerulus

Question 77

____ _____ is the temperature at which performance is maximized

Answer 77

thermal optimum

Question 78

for effective urine filtration, the blood pressure must _____ the sum of the colloid osmotic pressure and the capsular hydrostatic pressure

Answer 78

greater

Question 79

mass-specific metabolic rate _____ with increasing body weight

Answer 79

decreases

Question 80

The energy cost of moving a given distance that is independent of time and speed is called _________________.

Answer 80

net cost of transport

Question 81

The minimal cost of transport in swimming and flying organisms is attained at _______ speeds

Answer 81

intermediate

Question 82

increased metabolic rate due to activation of digestive processes is known as _________________.

Answer 82

system dynamic action

Question 83

Draw the relationship between metabolic rate and speed during terrestrial locomotion (left graph). Draw and explain how total cost of transport varies with locomotor speed and indicate the speed at which locomotion is most economical (right graph) LABEL AXES

Answer 83

TCOT decreases exponentially as locomotor speed increases. The speed at which locomotion is most economical is at maximal aerobic speed

Question 84

Explain a mechanism resulting in extreme freeze tolerance in some amphibians

Answer 84

Low molecular weight carbohydrates (glucose and glycerol) serve anti-freeze and cryoprotectant functions. They will mobilize glucose and show a pattern of enzyme activation during freezing

Question 85

describe the difference in the relative medullary thickness of mammals inhabiting arid, mesic, and aquatic habitats. Include in your answer an explanation of why this difference exists

Answer 85

Mammals inhabiting aquatic habitats don't have a very thick medullary. This is because they live in water so they don't have to worry about dehydration. Mammals inhabiting arid habitats will have a thicker medullary because they live in hot, dry environments so they have a thicker medullary to be able to hold onto water inside. Mammals inhabiting mesic habitats will have an intermediately thick medullary because they live in "tropical" environments so their medullary doesn't need to be too thick or thin

Question 86

Using the graph below, explain how the thermal sensitivity of O2 consumption responds to temperature in two different time frames.

Answer 86

For the chronic response, 16 acclimated lizards had a higher metabolic rate than the 33 lizards. This is indicated by the increase in O2 consumption at each point on the 16 acclimated line. The acclimation increased the thermal sensitivity of O2 consumption for the 16 acclimated lizards. For the acute response the 16 acclimated lizard had a higher metabolic rate than the 33 acclimated lizards.

Question 87

Explain why indirect calorimetry does not always provide a perfect measurement of metabolic rate.

Answer 87

There is a fixed O2:CO2 ratio when carbohydrates are being catabolized. The problem is, organisms don't just consume carbohydrates so the ratio calculations would be inaccurate. We can figure out what foods are being metabolized by using the RQ