Deck 39: Animal Form and Function

Question 1

An elephant and a mouse are both running in full sunlight, and both overheat by the same amount above their normal body temperatures. When they move into the shade and rest, which animal will cool down faster?

A) They will cool at the same rate because they overheated by the same amount.
B) The elephant will because it has the lower surface area/volume ratio.
C) The elephant will because it has the higher surface area/volume ratio.
D) The mouse will because it has the lower surface area/volume ratio.

Answer 1

D

Question 2

What is the stratified epithelium composed of?

A) a tight layer of square cells attached to a basement membrane
B) alternating layers of thick and thin cells
C) multiple layers of cells, stacked from the basolateral side to the apical side
D) a single layer of cells of variable height
E) squamous cells overlying cuboidal cells

Answer 2

C

Question 3

Which of the following is a true statement about body size and physiology?

A) The rate at which an animal uses nutrients and produces waste products is independent of its volume.
B) The wastes produced by an animal double as its volume doubles, and triple as its surface area triples.
C) Small and large animals face different physiological challenges because an animal's body mass increases cubically while its surface area increases as a squared function.
D) The amount of food and oxygen an animal requires and the amount of heat and waste it produces are inversely proportional to its mass.

Answer 3

C

Question 4

You begin exercising vigorously. This will, in a short time, cause your blood pH to begin dropping due to the release of carbon dioxide into your bloodstream. Which component of your homeostatic feedback system is responsible for deciding if your blood pH is far enough from normal that a response is necessary?

A) assimilator
B) integrator
C) sensor
D) effector

Question 5

Which one of the following is not a good strategy for increasing the surface area relative to the volume?

A) Enlarge and make more spherical.
B) Make flatter.
C) Increase the amount of folding.
D) Increase the amount of branching.
E) None of these are good strategies.

Question 6

Epithelial cells have multiple functions. They may have different structures on one of their surfaces compared to their opposite surface. What property of these cells allows them to undergo these various functions?

A) Epithelial cells are polar.
B) Epithelial cells have an apical membrane and a basolateral membrane.
C) Epithelial cells have different proteins in different parts of their cell membrane.
D) Only A and B are true.
E) A, B, and C are all true.

Question 7

Epithelial tissues have polarity, with an apical side that faces the environment and a basolateral side that faces the interior of the animal. Because of the harsh environmental exposure on the apical side, epithelial cells have a short life span of 2- 6 days. Which of the following is the most likely reason that the tissue as a whole does not wear away, despite the short life spans of the cells?

A) The epithelial tissue is unusually thick.
B) The tissue has cells that actively undergo mitosis and cytokinesis to replace the lost cells.
C) The degraded tissue is recycled and restored to its original site.
D) New cells are transported in the blood to the site where old cells have worn away.

Question 8

You discover a new species of bacteria that grows in aquatic environments with high salt levels. While studying these bacteria, you note that their internal environment is similar to the salt concentrations in their surroundings. You also discover that the internal salt concentrations of the bacteria change as the salt concentration in their environment changes. The new species can tolerate small changes in this way, but dies from large changes because it has no mechanism for altering its own internal salt levels. What type of homeostatic mechanism is this species using to regulate its internal salt levels?

A) assimilation
B) regulation
C) integration
D) conformation
E) all of the above

Question 9

Wading birds in northern climates are able to walk in pools of water on ice without dying of hypothermia because they have countercurrent heat exchangers in their legs. These exchangers allow heat in warm blood going to the feet to be transferred to cool blood returning from the feet. Why are such countercurrent heat exchangers so efficient at conserving heat?

A) The gradient between the two currents is maintained even as one current cools and the other current heats.
B) There is a large temperature differential from one end of each current to the other.
C) Blood in the arteries and veins flow in the same direction, so there is no loss to friction.
D) All of the above apply.
E) A and B only apply.

Question 10

How do the epithelial tissues covering organisms contribute to the maintenance of homeostasis?

A) They act as a barrier to create an internal environment different from the external environment.
B) They regulate the exchange of ions between the body and the environment.
C) They help to prevent water loss from the body in a terrestrial environment.
D) All of the above answers apply.
E) Only A and C apply.

Question 11

A researcher is setting up an experiment to measure basal metabolic rate in prairie voles a small mouse- like mammal). Which of the following would be the best set of conditions for the voles immediately before and during the measurement?

A) House in a cage with plenty of food and water to avoid stress; conduct measurements in a room the same temperature as the room where housed.
B) House in a cage with plenty of food and water to avoid stress; conduct measurements in a warmer room than the room where housed.
C) House in a cage with no food for a few hours before measurement; conduct measurements in a colder room than the room where housed, and exercise the voles.
D) House in a cage with no food for a few hours before measurement; conduct measurements in a room the same temperature as the room where housed.

Question 12

A woman standing and watching the stars on a cool, calm night will lose most of her body heat by which mechanism?

A) radiation
B) convection
C) conduction
D) evaporation
E) A and B only

Question 13

Natural selection involves energetic trade- offs between which of the following?

A) increasing the number of individuals produced during each reproductive episode and a corresponding decrease in parental care
B) choosing how many offspring to produce over the course of a lifetime and how long to live
C) producing large numbers of gametes when employing internal fertilization versus fewer numbers of gametes when employing external fertilization
D) high survival rates of offspring and the cost of parental care
E) the emigration of individuals when they are no longer reproductively capable or committing suicide

Question 14

Some animals have no gills when young, but then develop gills that grow larger as the animal grows larger. What is the reason for this trend?

A) The young of these animals are much more active than the adult.
B) Relative to their volume, the young have more surface area across which they can transport all the oxygen they need.
C) The young have a higher basal metabolic rate.
D) Relative to their surface area, the young have more volume in which they can store oxygen for long periods of time.

Question 15

A behavioural physiologist is studying the homeostatic control of blood pH. In a trial, a lizard runs on a treadmill for a set amount of time and the blood pH is measured. The blood pH drops as carbon dioxide is released into the bloodstream. Which component of the homeostatic feedback system is responsible for determining whether the blood pH is far enough from normal that a response is necessary?

A) effector
B) integrator
C) assimilator
D) sensor

Question 16

Your professor announces he has discovered a new species of bird that feeds mostly on worms and soft- bodied insects picked up from the ground and off of leaves. Based on this information, what shape of beak would you predict for this bird?

A) long and narrow like tweezers
B) medium- sized and very strong
C) wide and curved like a scoop
D) deep and powerful

Question 17

Salmon are born in freshwater environments and then migrate to the sea. Near the end of their lives, they return to the freshwater stream where they were born to spawn. In freshwater, water constantly diffuses into the body and ions are lost from the body. In salt water, body water diffuses out of the body and excess ions are gained from the water. A salmon's gills have special cells to pump salt in or out of the body to maintain homeostasis. In response to the salmon's moves between freshwater and salt water, some cells in the gills are produced and others are destroyed. These changes made in the cells of the gills during the lifetime of an individual salmon are an example of which of the following?

A) acclimatization
B) natural selection
C) adaptation
D) trade- off

Question 18

Which class of tissue has many different types and functions in humans dictated by the unique extracellular matrix surrounding that tissue?

A) muscle
B) nervous
C) epithelial
D) connective
E) none of the above

Question 19

What does the large surface area in the small intestine directly facilitate?

A) secretion
B) filtration
C) elimination
D) absorption
E) temperature regulation

Question 20

Which of the following is not a function of an effector in the homeostatic regulation of temperature in mammals?

A) constriction of skin blood vessels to decrease heat loss
B) shivering to generate heat in muscles
C) comparing sensory input to the set point
D) stimulating sweat glands to increase evaporation
E) both A and D

Question 21

Which of the following scenarios illustrates the physiological response of acclimatization?

A) Desert- dwelling plants such as the cactus have developed long root systems to ensure that they get enough water.
B) A dog sheds its thick winter fur for a lighter coat of fur when the temperature warms in the spring and summer.
C) Genetic changes have occurred in populations that have lived high in the Alps for many generations that allow individuals in these populations to cope with an environment with low oxygen.

Question 22

Scientists have performed studies to show that having a fever is adaptive. Which of the following observations in an ectotherm would be consistent with this conclusion?

A) An ectotherm with a fever will tend to stay warm by covering with a blanket.
B) An ectotherm with a fever will seek out cooler environments, like a tub of cool water.
C) An ectotherm will develop a fever after an infectious organism has been destroyed in order to speed healing.
D) An ectotherm with a fever will tend to decrease overall activity levels in order to keep from overheating.

Question 23

You are a doctor and you are given the files of two patients who are identical twin brothers: Patient #1: 25 year old male, 30% muscle mass, 70% fat content, 37 degrees C internal temperature Patient #2: 25 year old male, 70 % muscle mass, 30% fat content, 37 degrees C internal temperature
If you are told that both patients are equally active and are completely healthy, which of the following assumptions can we make regarding the metabolic rates of the brothers?

A) Patient # 1 likely has a lower metabolic rate than Patient # 2.
B) Patient # 1 and Patient # 2 likely have the same metabolic rate.
C) Patient # 1 likely has a higher metabolic rate than Patient # 2.

Question 24

Which term best describes an animal that, although generating a significant amount of heat through metabolism, nonetheless does not maintain a constant body temperature?

A) heterothermic endotherm
B) homeothermic endotherm
C) heterothermic ectotherm
D) homeothermic ectotherm

Question 25

Which of the following is an example of a structure that has an increased surface area for absorption?

A) an earthworm's segmented body
B) a cheetah's large nostrils
C) a human's lungs with many thin- walled alveoli
D) a cow's digestive tract consisting of 3 stomachs

Question 26

Use the following information when answering the question below.
The crucian carp Carassius carassius) is a Northern European freshwater fish often inhabiting ponds that become hypoxic hav reduced oxygen levels) and even anoxic have no oxygen) when the surface freezes during the winter. Surprisingly, when oxygen levels are normal, these fish lack the lamellae that provide a large surface area for gas exchange between water and blood: their gills are smooth. Yet when the level of oxygen in the water falls, the gill morphology undergoes a change:
packing cells stop dividing and programmed cell death is induced, exposing gill lamellae that were buried in other tissue. With lamellae exposed, the gills have increased surface area for gas exchange. These changes in gill lamellar profile are reversible: investigators observed that the gills return to their normal structure within 7 days after returning the fish to
well- oxygenated water. Jørund Sollid, Paula De Angelis, Kristian Gundersen, and Göran E. Nilsson. 2003. Hypoxia induces adaptive and reversible gross morphological changes in crucian carp gills. Journal of Experimental Biology 206:3667- 73.)
Gills serve multiple functions in fish in addition to gas exchange. Given the large surface area of gills with lamellae, what is the most likely explanation for why crucian carp cover protruding lamellae in their gills when levels of oxygen are normal?

A) to prevent loss of heat to the surrounding water
B) to prevent protein loss to the surrounding water
C) to prevent loss of ions to the surrounding water
D) to prevent loss of oxygen to the surrounding water

Question 27

Which of the following is an example of negative feedback?

A) During birthing contractions, the hormone oxytocin is released and acts to stimulate further contractions.
B) When blood glucose concentration increases, the pancreas produces and releases the hormone insulin. Insulin acts to decrease blood glucose. As blood glucose decreases, the rate of production and release of insulin decreases.
C) When a baby is nursing, suckling leads to the production of more milk and a subsequent increase in the secretion of prolactin, which in turn stimulates lactation.
D) After a blood vessel is damaged, signals are released by the damaged tissues that activate platelets in the blood. These activated platelets release chemicals that activate more platelets.

Question 28

Which of the following statements comparing endotherms and ectotherms is FALSE?

A) Mitochondrial density and enzyme activity are 3- 4 times higher in the cells of endotherms than in the cells of ectotherms of similar size.
B) Ectotherms can use more of their energy intake for reproduction than endotherms can.
C) Endotherms and ectotherms have about the same mass- specific metabolic rate.
D) Both endotherms and ectotherms exchange heat with the environment through convection, conduction, radiation, and evaporation.
E) B, C, and D are all false.

Question 29

Structure- function correlations exist throughout nature at all levels of organization, from the cellular level to systems level. Keeping this in mind, you visualize a cell under a microscope and it contains a lot of rough endoplasmic reticulum. What might you hypothesize the primary function of the cell to be?

A) participation in the immune response
B) energy storage
C) hormone protein) synthesis and release
D) conduction of electrical signals

Question 30

Which of the following explanations for brown adipose tissue explains why infant humans and some small mammals have this tissue type?

A) This tissue stores more heat than other types of fat because of its darker colour.
B) This tissue can convert ATP into heat energy instead of using it for muscle contraction and other energy- requiring processes.
C) This tissue allows for the conversion of fats directly into heat without the production of ATP.
D) This tissue type has less water than other adipose tissues and thus has less evaporative cooling.

Question 31

Many types of ectothermic animals can be seen lying out in the sun on a warm, sunny day. What is the primary mechanism by which the animal warms itself during this activity?

A) conduction
B) radiation
C) evaporation
D) convection

Question 32

Natural selection has contributed to the wide variety of beak morphologies exhibited by the Galápagos Island finches. A correlation exists whereby beak morphology suggests the primary food source of the finch. Which physiological response listed below best describes the variety of beak morphologies seen in these finches?

A) acclimation
B) acclimatization
C) adaptation

Question 33

Torpor has evolved in several high- latitude species even though it is energetically expensive. Why does this adaptation require a large energy input for those species that utilize this function?

A) During torpor, animals undergo excessive shivering to maintain their body temperature.
B) Animals in torpor lower their body temperature dramatically and require a great deal of energy to bring the body temperature back up to normal.
C) It takes a great deal of energy to stay alive when the body temperature drops to near ambient levels.
D) These animals expend a great deal of metabolic energy to maintain their body temperature as the ambient temperatures drop.

Question 34

Which principle of heat exchange is the most important explanation for why birds look larger in colder weather because they fluff their feathers?

A) Fluffing creates a pocket of air near the bird that acts as insulation.
B) Fluffing decreases the surface area/volume ratio, thus decreasing the amount of heat lost to the environment.
C) Fluffing feathers results in less cooling by radiation since feathers emit less infrared radiation than other tissues do.
D) Fluffing decreases the amount of heat lost by conduction when the bird makes contact with cold objects in its environment.

Question 35

What is the main reason that a person sitting on the beach with an air temperature of 15°C loses heat less rapidly than when immersed in lake water at 15°C?

A) Metabolic heat production is greater in air than in water.
B) Air is a poor insulator.
C) Water conducts heat more efficiently than air does.
D) Water evaporates, and heat is lost to evaporation.

Question 36

After you eat a meal, blood glucose concentration increases. Insulin is released from the pancreas to restore blood glucose concentration by facilitating the uptake of glucose by cells and stimulating the conversion of glucose to glycogen. What homeostatic mechanism is this an example of?

A) negative feedback
B) positive feedback
C) feedback inhibition
D) neutralizing feedback

Question 37

Multicellular organisms are limited by size and, thus, ways to increase surface area of a structure are often advantageous. Which of the following pairs of words best describes ways to increase the surface area of a structure?

A) shortening and flattening
B) flattening and converging
C) shortening and converging
D) folding and branching