Final Exam pt 1

Question 1

Hormones:

a. are used by the endocrine system to communicate signals
b. must bind to a receptor to cause a response in the target cells
c. travel through the bloodstream to reach their target
d. all of the above

Answer 1

d. all of the above

Question 2

Examples of ways that animals and plants increase surface area for exchange include:

a. the flat body plans of flatworms
b. folding of the thylakoid discs in chloroplasts
c. branched filaments of fungi mycelium
d. all of the above

Answer 2

d. all of the above

Question 3

Compared with a smaller cell, a larger cell of the same shape has:

a. less surface area per unit of volume
b. the same surface area-to-volume ratio
c. less surface area
d. a more specialized function

Answer 3

a. less surface area per unit of volume

Question 4

When you touch a hot pan on the stove, temperature sensors in the skin send a message to the spinal cord, which directs your skeletal muscles to pull your hand away. In this scenario, the spinal cord is the:

a. receptor
b. conductor
c. control center
d. defender

Answer 4

c. control center

Question 5

After you eat, your blood glucose rises. Your body then releases a hormone that triggers mechanisms to reduce your blood sugar to homeostatic levels. This regulation of blood glucose is an example of:

a. positive feedback
b. negative feedback
c. doubleback feedback
d. not an example of feedback

Answer 5

b. negative feedback

Question 6

You are studying a large tropical reptile that has a high and relative stable body temperature. Which of the following describe the best way to determine whether this animal is a regulator or conformer for temperature:

a. You observe that its environment has a high and stable temperature. Because its body temperature matches the environmental temperature, you conclude that it is a conformer.
b. You subject the reptile to various temperatures in the lab and find that its body temperature and metabolic rate change with the environmental temperature. You conclude that it is a conformer.
c. You know from its high and stable body temperature that it must be a regulator.
d. You subject the reptile to various temperatures in the lab and find that its body temperature and metabolic rate do not change with the environmental temperature. You conclude that it is a conformer.

Answer 6

b. You subject the reptile to various temperatures in the lab and find that its body temperature and metabolic rate change with the environmental temperature. You conclude that it is a conformer.

Question 7

On a hot day, you feel cooler when there is a breeze blowing than when there is not. This is because:

a. radiant heat waves from the sun are being absorbed by the body
b. heat is being moved away from the body through convection
c. heat is being moved into the body through convection
d. heat is being moved away from the body through conduction

Answer 7

b. heat is being moved away from the body through convection

Question 8

8. For animals who have their extremities (fins, feet, etc.) in extended contact with cold water:
   a. heat loss is minimized by radiation between the water and the extremities
   b. heat loss is minimized by heat transfer from the blood in the arteries to that of the veins
   c. heat loss is minimized by evaporation
   d. heat loss is maximized by heat transfer from the blood in the arteries to that of the veins

Answer 8

b. heat loss is minimized by heat transfer from the blood in the arteries to that of the veins

Question 9

Behavioral adaptations for thermoregulation include:

a. physical contact with other organisms (huddling)
b. hibernation
c. migration
d. all of the above

Answer 9

d. all of the above

Question 10

Which of the following would decrease the amount of heat lost from an animal to its environment:

a. fur
b. vasodilation of surface vessels
c. perspiration
d. all of the above

Answer 10

a. fur

Question 11

Consider a human, a mouse, and an elephant. Which of the following are true:

a. the human has the greatest total energy expenditure
b. the mouse has the greatest energy expenditure per kg
c. all three animals are endotherms, and therefore expend the same total amount of energy

Answer 11

b. the mouse has the greatest energy expenditure per kg

Question 12

On a hot day, temperature sensors send a signal to the hypothalamus that the body temperature is increasing. The hypothalamus:

a. triggers sweating to cool the body through evaporation
b. triggers contraction of the skeletal muscles to generate heat
c. is functioning as the deffector in the internal control mechanism
d. both a and c
e. all of the above

Answer 12

a. triggers sweating to cool the body through evaporation

Question 13

Based on the example illustrated above:

a. the body temperature of the snake would be expected to go up as the number of contractions per minute increases
b. oxygen consumption increases as the number of contractions per minute increases
c. ectotherms have some limited ability for thermogenesis in certain situations
d. all of the above

Answer 13

d. all of the above

Question 14

Consider the energy budgets for a 4 kg penguin, a 0.025 kg mouse, and a 4 kg snake. Which of the following would you predict:

a. the penguin will have the same metabolic rate as the snake
b. the mouse will spend a smaller proportion of its energy on thermoregulation than the penguin
c. the snake will spend about the same proportion of energy on thermoregulation as the penguin
d. none of the above

Answer 14

d. none of the above

Question 15

As the size of some animals has evolved to greater sizes, the effectiveness of their adaptations that promote exchanges with the environment have also increased. For example, in many larger organisms, evolution has favored lungs and a digestive tract with _____.

a. more branching or folds
b. increased thickness
c. larger cells
d. decreased blood supply

Answer 15

a. more branching or folds

Question 16

16. Epithelium that functions in secretion or absorption would most likely:
    a. be stratified epithelium
    b. consist of multiple layers of cells
    c. consists of a single layer of cells
    d. both a and b
    e. both a and c

Answer 16

c. consists of a single layer of cells

Question 17

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 increase in gill size?

a. The young of these animals are much more active than the adult, which leads to a higher BMR (basal metabolic rate) and, therefore, a higher need for oxygen.
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 body volume in which they can store oxygen for long periods of time.

Answer 17

b. Relative to their volume, the young have more surface area across which they can transport all the oxygen they need.

Question 18

Sheets of tightly packed cells attached on one side to a basement membrane:

a. is a description of connective tissue
b. describes the lining of the hollow organs, such as the stomach
c. always contracts when stimulated by nervous signals
d. all of the above

Answer 18

b. describes the lining of the hollow organs, such as the stomach

Question 19

Interstitial fluid is _____.

a. the internal environment inside animal cells
b. identical to the composition of blood
c. a common site of exchange between blood and body cells
d. found only in the lumen of the small intestine

Answer 19

c. a common site of exchange between blood and body cells

Question 20

Skeletal muscle

a. pumps blood
b. propels substances through the digestive tract and other hollow organs
c. moves the skeletal parts

Answer 20

c. moves the skeletal parts

Question 21

Much of the coordination of vertebrate body functions via chemical signals is accomplished by the _____.

a. respiratory system
b. endocrine system
c. integumentary system
d. excretory system

Answer 21

b. endocrine system

Question 22

22. Bone:
    a. is a form of epithelial tissue
    b. provides physical support to the body
    c. secretes an extracellular matrix rich in chondroitin sulfate
    d. all of the above

Answer 22

b. provides physical support to the body

Question 23

Loose connective tissue:

a. contains collagen and elastin
b. examples include tendons and ligaments
c. is comprised of adipocytes
d. is not a real type of tissue
e. all of the above

Answer 23

a. contains collagen and elastin

Question 24

The type of muscle tissue surrounding the intestines and blood vessels is _____.

a. skeletal muscle
b. cardiac muscle
c. intercalated cells
d. smooth muscle

Answer 24

d. smooth muscle

Question 25

When food is broken down into nutrients:

a. the energy released when bonds are broken is stored as ATP
b. heat is produced
c. carbon atoms from the nutrients may be used to build new molecules
d. all of the above

Answer 25

d. all of the above

Question 26

Metabolic rate is affected by:

a. size of the organism
b. activity level of the organism
c. whether the organism is an endotherm or ectotherm
d. all of the above

Answer 26

d. all of the above

Question 27

An animal’s diet must:

a. provide fuel for cells
b. provide organic materials for the synthesis of proteins, lipids, carbohydrates, and nucleic acids
c. supply both enough calories and essential nutrients
d. all of the above

Answer 27

d. all of the above

Question 28

Elimination:

a. is taking food into the digestive tract
b. is the chemical breakdown of food particles into absorbable nutrients
c. is the exit of undigested material from the digestive tract
d. is the process of cells taking up small molecules from the digestive tract

Answer 28

c. is the exit of undigested material from the digestive tract

Question 29

29. Extracellular digestion:
    a. occurs in bacteria
    b. occurs frequently in single-cell eukaryotes
    c. Is defined as the breakdown of proteins within each body cell
    d. occurs in alimentary canals
    e. all of the above

Answer 29

d. occurs in alimentary canals

Question 30

A gastrovascular cavity:

a. both digests and circulates nutrients
b. has specialized regions for different tasks
c. has two openings
d. all of the above

Answer 30

a. both digests and circulates nutrients

Question 31

A maggot lives in its food source (rotting meat). This makes it a:

a. a bulk feeder
b. a filter feeder
c. a fluid feeder
d. a substrate feeder

Answer 31

d. a substrate feeder

Question 32

A fatty acid that has been absorbed into an intestinal cell:

a. is hydrolyzed to smaller fragments
b. is packaged with phospholipids, cholesterol, and proteins into a chylomicron
c. was originally a carbohydrate
d. will be added to fat located in the earlobe

Answer 32

b. is packaged with phospholipids, cholesterol, and proteins into a chylomicron

Question 33

An herbivore:

a. has a shorter digestive tract than a carnivore
b. unlike carnivores, has enzymes that are capable of digesting cellulose
c. typically has a larger cecum than a carnivore
d. all of the above

Answer 33

c. typically has a larger cecum than a carnivore

Question 34

A carnivore:

a. typically has larger, more pointed incisors and canines than an herbivore
b. have broad, ridged molars and premolars
c. has teeth adapted to eating both plants and animals
d. generally has more teeth than a herbivore

Answer 34

a. typically has larger, more pointed incisors and canines than a herbivore

Question 35

Which of the following correctly describes the path of food through the digestive system of a cow:

a. digestion by microorganisms in the reticulum & rumen, regurgitation into the oral cavity for more chewing, movement into the omasum & abomasum for digestion by the cow’s own digestive enzymes
b. digestion by microorganisms in the reticulum & rumen, movement into the omasum & abomasum for digestion by the cow’s own digestive enzymes, regurgitation into the oral cavity for more chewing
c. movement into the omasum & abomasum for digestion by the cow’s own digestive enzymes, digestion by microorganisms in the reticulum & rumen, regurgitation into the oral cavity for more chewing

Answer 35

a. digestion by microorganisms in the reticulum & rumen, regurgitation into the oral cavity for more chewing, movement into the omasum & abomasum for digestion by the cow’s own digestive enzymes

Question 36

36. An elephant and a mouse are running in full sunlight, and both overheat by the same amount above their normal body temperatures. When they move into the shade and rest, the mouse will cool to its normal temperature faster.
    a. True
    b. False

Answer 36

a. True

Question 37

Cholecystokinin (CCK):

a. inhibits the release of gastric juices from the stomach if chime is rich in fats
b. stimulates the release of bicarbonate from the pancreas when food arrives in the small intestine
c. is produced by the stomach
d. all of the above

Answer 37

a. inhibits the release of gastric juices from the stomach if chime is rich in fats

Question 38

Glucagon:

a. is released in response to elevated blood glucose stimulates the liver to break down glycogen and release the glucose into the bloodstream
b. tells the liver to make more glycogen
c. tells the brain that it needs more sugar
d. A & C

Answer 38

a. is released in response to elevated blood glucose stimulates the liver to break down glycogen and release the glucose into the bloodstream

Question 39

Diabetes mellitus:

a. results in high blood sugar levels (hyperglycemia)
b. results in symptoms of decreased urination and thirst
c. results in the production of basic metabolites that increase blood pH
d. all of the above

Answer 39

a. results in high blood sugar levels (hyperglycemia)

Question 40

Type 1 diabetes mellitus:

a. is the result of decreased response to insulin by the cells
b. can be treated with diet and exercise
c. is the result of destruction of the beta cells, which leads to an insulin deficiency
d. both b and c

Answer 40

c. is the result of destruction of the beta cells, which leads to an insulin deficiency

Question 41

The term that best describes the relationship between humans and the bacteria living within the alimentary canal is:

a. parasitic
b. predatory
c. mutualistic
d. pathological

Answer 41

c. mutualistic

Question 42

From a scientific standpoint, the organs that carry out physiological functions in animals can best be thought of as:

a. acclimations
b. adaptations
c. evidence for divine creation
d. good luck

Answer 42

b. adaptations

Question 43

The fact that growth and development of both animals and plants is controlled by hormones is evidence for the common ancestry of all life

a. True
b. False

Answer 43

a. True

Question 44

An example of a properly functioning homeostatic control system is seen when _____.

a. the core body temperature of a runner rises gradually from 37°C to 45°C
b. the kidneys excrete salt into the urine when dietary salt levels rise
c. a blood cell shrinks when placed in a solution of salt and water
d. the blood pressure increases in response to an increase in blood volume

Answer 44

b. the kidneys excrete salt into the urine when dietary salt levels rise

Question 45

Sharks, penguins, and aquatic mammals such as seals:

a. have fusiform body shapes
b. have similar body shapes because they face similar environmental challenges and the same body form is an advantage
c. have a similar body form due to natural selection
d. all of the above

Answer 45

d. all of the above

Question 46

You are dissecting a fish in your biology laboratory section. Your teaching assistant points out a long oval structure and tells you it is an endocrine gland. Which of the following would you then know is a true statement about this structure?
A) It secretes a product that is released through a series of ducts.
B) The gland’s product will only interact with receptors on the cell membrane.
C) The gland’s product is lipid soluble.
D) The gland produces and secretes its product into the blood.

Answer 46

D) The gland produces and secretes its product into the blood.

Question 47

What is the only type of chemical signal that does not alter the physiology of the animal producing that signal?
A) neural
B) paracrine
C) neuroendocrine
D) pheromones

Answer 47

D) pheromones

Question 48

4) Testosterone is an example of a chemical signal that affects the very cells that synthesize it, the neighboring cells in the testis, along with distant cells outside the gonads. Thus, testosterone is an example of \_\_\_\_\_.
I)	an autocrine signal
II)	a paracrine signal
III)	an endocrine signal
A) only I and II 
B) only II and III
C) only I and III
D) I, II, and III

Answer 48

D) I, II, and III

Question 49

Prostaglandins are local regulators whose chemical structure is derived from \_\_\_\_\_.
A) oligosaccharides
B) fatty acids
C) steroids
D) amino acids

Answer 49

B) fatty acids

Question 50

A cell with membrane-bound proteins that selectively bind a specific hormone is called that hormone's \_\_\_\_\_.
A) secretory cell
B) endocrine cell
C) target cell
D) regulatory cell

Answer 50

C) target cell

Question 51

Different body cells can respond differently to the same peptide hormones because _____.
A) different target cells have different sets of genes
B) a target cell’s response is determined by the components of its signal transduction pathways
C) the circulatory system regulates responses to hormones by routing the hormones to specific targets
D) the hormone is chemically altered in different ways as it travels through the circulatory system

Answer 51

B) a target cell’s response is determined by the components of its signal transduction pathways

Question 52

When a steroid hormone and a peptide hormone exert similar effects on a population of target cells, then _____.
A) the steroid and peptide hormones must use the same biochemical mechanisms
B) the steroid and peptide hormones must bind to the same receptor protein
C) the steroid hormones affect the synthesis of effector proteins, whereas peptide hormones activate effector proteins already present in the cell
D) the steroid hormones affect the activity of certain proteins within the cell, whereas peptide hormones directly affect the processing of mRNA

Answer 52

C) the steroid hormones affect the synthesis of effector proteins, whereas peptide hormones activate effector proteins already present in the cell

Question 53

Based on their effects, which pair below would NOT be expected to be active at the same time and place?
A) prostaglandin and nitric oxide
B) endocrine and exocrine glands
C) hormones and target cells
D) neurosecretory cells and neurotransmitters

Answer 53

A) prostaglandin and nitric oxide

Question 54

Polypeptides can have which of the following types of effects?
I)	autocrine
II)	paracrine
III)	endocrine
A) only I and III
B) only II and III
C) only I and II
D) I, II, and III

Answer 54

D) I, II, and III

Question 55

A cluster of tumor cells that produces and secretes growth factors to induce surrounding cells to grow and divide is showing which type of cell-to-cell signaling?
A) autocrine
B) paracrine
C) endocrine
D) neuroendocrine

Answer 55

B) paracrine

Question 56

14) Growth factors are local regulators that _____.
A) are modified fatty acids that stimulate bone and cartilage growth
B) are found on the surface of cancer cells and stimulate abnormal cell division
C) bind to cell-surface receptors and stimulate growth and development of target cells
D) convey messages between nerve cells

Answer 56

C) bind to cell-surface receptors and stimulate growth and development of target cells

Question 57

The steroid hormone that coordinates molting in arthropods is \_\_\_\_\_.
A) ecdysteroid
B) glucagon
C) thyroxine
D) growth hormone

Answer 57

A) ecdysteroid

Question 58

Insect hormones and their receptors _____.
A) act independently of each other
B) are a focus in pest control research
C) utilize cell-surface receptors only
D) are active independently of environmental cues

Answer 58

B) are a focus in pest control research

Question 59

During mammalian labor and delivery, the contraction of uterine muscles is enhanced by oxytocin. This is an example of _____.
A) a negative feedback system
B) a hormone that acts in an antagonistic way with another hormone
C) a hormone that is involved in a positive feedback loop
D) signal transduction immediately changing gene expression in its target cells

Answer 59

C) a hormone that is involved in a positive feedback loop

Question 60

Which of the following has both endocrine and exocrine activity?
A) the pituitary gland
B) parathyroid glands
C) salivary glands
D) the pancreas

Answer 60

D) the pancreas

Question 61

When the beta cells of the pancreas release insulin into the blood, _____.
A) the skeletal muscles and the adipose cells take up glucose at a faster rate
B) the liver catabolizes glycogen
C) the alpha cells of the pancreas release glucose into the blood
D) the kidneys begin gluconeogenesis

Answer 61

A) the skeletal muscles and the adipose cells take up glucose at a faster rate

Question 62

The steroid hormone that coordinates molting in arthropods is \_\_\_\_\_.
A) ecdysteroid
B) glucagon
C) thyroxine
D) growth hormone

Answer 62

A) ecdysteroid

Question 63

An example of antagonistic hormones controlling homeostasis is _____.
A) thyroxine and parathyroid hormone in calcium balance
B) insulin and glucagon in glucose metabolism
C) progestins and estrogens in sexual differentiation
D) epinephrine and norepinephrine in fight-or-flight responses

Answer 63

B) insulin and glucagon in glucose metabolism

Question 64

The relationship between the insect hormones ecdysteroid and PTTH is an example of _____.
A) an interaction of the endocrine and nervous systems
B) competitive inhibition of a hormone receptor
C) how peptide-derived hormones have more widespread effects than steroid hormones
D) homeostasis maintained by antagonistic hormones

Answer 64

A) an interaction of the endocrine and nervous systems

Question 65

33) Hormones secreted by the posterior pituitary gland are made in the \_\_\_\_\_.
A) cerebellum
B) thalamus
C) hypothalamus
D) medulla oblongata

Answer 65

C) hypothalamus

Question 66

The interrelationships between the endocrine and the nervous systems are especially apparent in a _____.
A) steroid-producing cell in the adrenal cortex
B) neurosecretory cell in the hypothalamus
C) brain cell in the cerebral cortex
D) cell in the pancreas that produces digestive enzymes

Answer 66

B) neurosecretory cell in the hypothalamus

Question 67

Portal blood vessels connect two capillary beds found in the _____.
A) hypothalamus and thalamus
B) anterior pituitary and posterior pituitary
C) hypothalamus and anterior pituitary
D) posterior pituitary and thyroid gland

Answer 67

C) hypothalamus and anterior pituitary

Question 68

If a person loses a large amount of water in a short period of time, he or she may die from dehydration. Antidiuretic hormone (ADH) can help reduce water loss through its interaction with its target cells in the \_\_\_\_\_.
A) anterior pituitary
B) posterior pituitary
C) bladder
D) kidney

Answer 68

D) kidney

Question 69

A product of the anterior pituitary gland that causes color changes in its target cells is \_\_\_\_\_.
A) follicle-stimulating hormone (FSH)
B) luteinizing hormone (LH)
C) thyroid-stimulating hormone (TSH)
D) melanocyte-stimulating hormone (MSH)

Answer 69

D) melanocyte-stimulating hormone (MSH)

Question 70

In a lactating mammal, the two hormones that promote milk synthesis and milk release, respectively, are _____.
A) prolactin and calcitonin
B) prolactin and oxytocin
C) follicle-stimulating hormone and luteinizing hormone
D) luteinizing hormone and oxytocin

Answer 70

B) prolactin and oxytocin

Question 71

41) Which endocrine disorder is correctly matched with the malfunctioning gland?
A) dwarfism — the adrenal cortex
B) gigantism — the anterior pituitary gland
C) goiter — the adrenal medulla
D) diabetes mellitus — the parathyroid glands

Answer 71

B) gigantism — the anterior pituitary gland

Question 72

Which of the following is the most likely explanation for hypothyroidism in a patient whose iodine level is normal?
A) greater production of T3 than of T4
B) hyposecretion of thyroid-stimulating hormone (TSH)
C) hypersecretion of thyroid-stimulating hormone (TSH)
D) a decrease in the thyroid secretion of calcitonin

Answer 72

B) hyposecretion of thyroid-stimulating hormone (TSH)

Question 73

When a person drinks alcohol, the rate of urination increases. This suggests that antidiuretic hormone (ADH) may be affected by alcohol consumption in some way. Which of the following best accounts for the increase in urination?
A) Alcohol stimulates the release of ADH.
B) Alcohol inhibits the release of ADH.
C) Alcohol inhibits the binding of ADH to receptors in the nephron.
D) Alcohol could inhibit ADH release or the binding of ADH to receptors in the nephron.

Answer 73

B) Alcohol inhibits the release of ADH.

Question 74

Removing which of the following glands would have the most wide-reaching effect on bodily functions of an adult human?
A) adrenal glands
B) pituitary gland
C) thyroid gland
D) ovaries (in female) or testes (in male)

Answer 74

B) pituitary gland

Question 75

Glucocorticoids do which of the following?
A) promote the immune response
B) promote the release of fatty acids
C) increase blood glucose levels
D) increase insulin production

Answer 75

C) increase blood glucose levels

Question 76

Nitric oxide and epinephrine \_\_\_\_\_.
A) both function as neurotransmitters
B) both function as steroid hormones
C) bind the same receptors
D) both cause a reduction in the blood levels of glucose

Answer 76

A) both function as neurotransmitters

Question 77

Fight-or-flight reactions include activation of the _____.
A) parathyroid glands, leading to increased metabolic rate
B) anterior pituitary gland, leading to cessation of gonadal function
C) adrenal medulla, leading to increased secretion of epinephrine
D) pancreas, leading to a reduction in the blood sugar concentration

Answer 77

C) adrenal medulla, leading to increased secretion of epinephrine

Question 78

The amino acid tyrosine is a starting substrate for the synthesis of \_\_\_\_\_.
A) epinephrine
B) steroid hormones
C) parathyroid hormone
D) acetylcholine

Answer 78

A) epinephrine

Question 79

A disease that destroys the adrenal cortex should lead to an increase in the plasma levels of \_\_\_\_\_.
A) glucocorticoid hormones
B) epinephrine
C) adrenocorticotropic hormone (ACTH)
D) acetylcholine

Answer 79

C) adrenocorticotropic hormone (ACTH)

Question 80

Of the following types of molecules, which can function as both neurotransmitters and hormones?
A) glucocorticoids
B) second messengers
C) catecholamines
D) adipocytes

Answer 80

C) catecholamines

Question 81

Predict the effects of a drug that increases adrenocorticotropic hormone (ACTH) synthesis.
A) increase in glucocorticoid production
B) increase in release of corticotropin-releasing hormone (CRH)
C) decrease in cortisol release
D) decrease in release of corticotropin-releasing hormone (CRH)

Answer 81

A) increase in glucocorticoid production

Question 82

58) Osteoporosis is a condition in which the density of bones is decreased so much that the individual is at a higher risk of fractures. The more calcium in the bones, the better the bone density. Which of the following would produce the greatest increase in bone calcium levels?
A) calcitonin injection 
B) calcitonin receptor blocker 
C) parathyroid hormone injection
D) glucagon receptor blocker

Answer 82

A) calcitonin injection

Question 83

People with type II diabetes mellitus have defective insulin receptors that cannot respond to insulin properly. Relative to normal individuals, what would be the effect on blood glucose levels under conditions of chronic stress that kept blood cortisol levels high? There would be _____.
A) a greater increase in blood glucose levels in individuals with type II diabetes mellitus than in normal individuals
B) less increase in blood glucose levels in individuals with type II diabetes mellitus than in normal individuals
C) be a greater decrease in blood glucose levels in individuals with type II diabetes mellitus than in normal individuals
D) less decrease in blood glucose levels in individuals with type II diabetes mellitus than in normal individuals

Answer 83

A) a greater increase in blood glucose levels in individuals with type II diabetes mellitus than in normal individuals

Question 84

In an experiment, rats' ovaries were removed immediately after impregnation and then the rats were divided into two groups. Treatments and results are summarized in the table above. The results most likely occurred because progesterone exerts an effect on the \_\_\_\_\_.
A) general health of the rat
B) metabolism of the uterus
C) gestation period of rats
D) number of eggs fertilized

Answer 84

B) metabolism of the uterus

Question 85

Epinephrine is an example of \_\_\_\_\_.
A) an androgen
B) an estrogen
C) a catecholamine
D) a glucocorticoid

Answer 85

C) a catecholamine

Question 86

DES is called an "endocrine disrupting chemical" because it structurally resembles, and interferes with, the endocrine secretions of the \_\_\_\_\_.
A) thyroid gland
B) adrenal medulla
C) ovaries
D) hypothalamus

Answer 86

C) ovaries

Question 87

Melatonin is secreted by the_____.
A) hypothalamus during the day
B) pineal gland during the night
C) autonomic nervous system during the winter
D) posterior pituitary gland during the day

Answer 87

B) pineal gland during the night

Question 88

In response to stress, the adrenal gland promotes the synthesis of glucose from non-carbohydrate substrates via the action of the steroid hormone \_\_\_\_\_.
A) glucagon
B) cortisol
C) thyroxine
D) adrenocorticotropic hormone (ACTH)

Answer 88

B) cortisol

Question 89

During a stressful interval, _____.
A) thyroid-stimulating hormaon (TSH) stimulates the adrenal cortex and medulla to secrete acetylcholine
B) the alpha cells of islets secrete insulin and simultaneously the beta cells of the islets secrete glucagon
C) adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex, and neurons of the sympathetic nervous system stimulate the adrenal medulla
D) the calcium levels in the blood are increased due to actions of two antagonistic hormones, epinephrine and norepinephrine

Answer 89

C) adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex, and neurons of the sympathetic nervous system stimulate the adrenal medulla

Question 90

Which of the following is the most likely explanation for the lack of a filter blocking the passage of alcohol between the maternal and fetal circulations in humans?
A) There has not been enough time to evolve such a barrier.
B) Such a barrier would probably also block important molecules that need to be passed to the fetus.
C) The maternal and fetal blood mix directly together in an area with many villi, so a barrier is impossible.
D) Alcohol has some positive effects on the fetus, so evolution has resulted in an intermediate level of filtering that blocks all but the worst abuses of alcohol.

Answer 90

B) Such a barrier would probably also block important molecules that need to be passed to the fetus.

Question 91

An ectopic pregnancy occurs when a fertilized egg implants somewhere other than in the lining of the uterus. Usually it implants in the oviduct. Which of the following would be the most likely explanation for such a pregnancy being unsuccessful?
A) The orientation of the baby would be sideways.
B) Human chorionic gonadotropin (hCG) cannot be produced in the oviduct.
C) The lining of the oviduct is unable to support the developing fetus.
D) The necessary hormones cannot reach the developing fetus in the oviduct.

Answer 91

C) The lining of the oviduct is unable to support the developing fetus.

Question 92

Based on the figure above, showing fetal (A) and adult (B) oxygen-hemoglobin saturation curves, which of the following conclusions is true?
A) The mother binds oxygen with greater affinity than the fetus.
B) Adult saturation occurs at lower partial pressures of oxygen than fetal saturation does.
C) At 50 percent saturation, fetal blood will have a higher affinity for oxygen than adult blood will.
D) As the partial pressure of oxygen increases, adult hemoglobin approaches saturation faster than fetal hemoglobin does.

Answer 92

C) At 50 percent saturation, fetal blood will have a higher affinity for oxygen than adult blood will.

Question 93

A pregnant woman comes into the hospital past her due date. The doctor decides it is time for the baby to be delivered. Before performing a cesarean section, the doctor wants to try to induce labor. Which of the following would she most likely inject?
A) progesterone
B) luteinizing hormone (LH)
C) follicle-stimulating hormone (FSH)
D) oxytocin

Answer 93

D) oxytocin

Question 94

Imagine that a woman is in the final week of her pregnancy. Her doctor gives her an injection of oxytocin. The likely result of this is that the pregnant woman would _____.
A) stop secreting prostaglandins from the placenta
B) undergo vigorous contractions of her uterine muscles
C) increase the synthesis and secretion of progesterone
D) be prevented from lactation

Answer 94

B) undergo vigorous contractions of her uterine muscles

Question 95

A vasectomy \_\_\_\_\_.
A) eliminates spermatogenesis
B) eliminates testosterone synthesis
C) prevents implantation of an embryo
D) prevents sperm from exiting the male urethra

Answer 95

D) prevents sperm from exiting the male urethra

Question 96

Tubal ligation _____.
A) reduces the incidence of ovulation
B) prevents fertilization by preventing sperm from entering the uterus
C) prevents sperm from exiting the male urethra
D) prevents oocytes from entering the uterus

Answer 96

D) prevents oocytes from entering the uterus

Question 97

Two contraceptive methods that are generally irreversible and which block the gametes from moving to a site where fertilization can occur are _____.
A) the male condom and female condom
B) the male condom and oral contraceptives
C) vasectomy and tubal ligation
D) the diaphragm and subcutaneous progesterone implant

Answer 97

C) vasectomy and tubal ligation

Question 98

In excreted urine, a reliable "marker" that a pregnancy has initiated is \_\_\_\_\_.
A) progesterone
B) estrogen
C) follicle-stimulating hormone
D) human chorionic gonadotropin (hCG)

Answer 98

D) human chorionic gonadotropin (hCG)

Question 99

Labor contractions can be increased by the medical use of a synthetic drug that mimics the action of \_\_\_\_\_.
A) inhibin
B) luteinizing hormone
C) oxytocin
D) prolactin

Answer 99

C) oxytocin

Question 100

Menopause is characterized by _____.
A) the loss of responsiveness by the ovaries to follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
B) a decline in production of the gonadotropin hormones by the anterior pituitary gland
C) wearing away of the uterine endometrium
D) a halt in the synthesis of gonadotropin-releasing hormone by the brain

Answer 100

A) the loss of responsiveness by the ovaries to follicle-stimulating hormone (FSH) and luteinizing hormone (LH)

Question 101

The primary function of the corpus luteum is to _____.
A) nourish and protect the egg cell
B) maintain progesterone and estrogen synthesis after ovulation has occurred
C) stimulate the development of the mammary glands
D) support pregnancy in the second and third trimesters

Answer 101

B) maintain progesterone and estrogen synthesis after ovulation has occurred

Question 102

In correct chronological order, the three phases of the human uterine cycle are \_\_\_\_\_.
A) follicular → luteal → secretory
B) menstrual → proliferative → secretory
C) follicular → ovulation → luteal
D) proliferative → luteal → ovulation

Answer 102

B) menstrual → proliferative → secretory

Question 103

A primary response by the Leydig cells in the testes to the presence of luteinizing hormone is an increase in the synthesis and secretion of \_\_\_\_\_.
A) inhibin
B) testosterone
C) oxytocin
D) progesterone

Answer 103

B) testosterone

Question 104

A reproductive hormone that is secreted directly from a structure in the brain is \_\_\_\_\_.
A) estradiol
B) progesterone
C) follicle-stimulating hormone (FSH)
D) gonadotropin-releasing hormone (GnRH)

Answer 104

D) gonadotropin-releasing hormone (GnRH)

Question 105

In correct chronological order, the three phases of the human ovarian cycle are \_\_\_\_\_.
A) follicular → luteal → secretory
B) menstrual → proliferative → secretory
C) follicular → ovulation → luteal
D) proliferative → luteal → ovulation

Answer 105

C) follicular → ovulation → luteal

Question 106

The primary difference between estrous and menstrual cycles is that _____.
A) the endometrium shed by the uterus during the estrous cycle is reabsorbed with no extensive fluid flow out of the body, whereas the shed endometrium of menstrual cycles is excreted from the body
B) behavioral changes during estrous cycles are much less apparent than those of menstrual cycles
C) season and climate have less pronounced effects on estrous cycles than they do on menstrual cycles
D) copulation normally occurs across the estrous cycle, whereas in menstrual cycles copulation only occurs during the period surrounding ovulation

Answer 106

A) the endometrium shed by the uterus during the estrous cycle is reabsorbed with no extensive fluid flow out of the body, whereas the shed endometrium of menstrual cycles is excreted from the body

Question 107

A male’s “primary” sex characteristics include _____.
A) deepening of the voice at puberty
B) development of the seminal vesicles and associated ducts
C) elongation of the skeleton prior to puberty
D) onset of growth of facial hair at puberty

Answer 107

B) development of the seminal vesicles and associated ducts

Question 108

A physician finds that a nine-year-old male patient is entering puberty much earlier than is usual. Such a condition is most likely the result of a tumor in the _____.
A) hypothalamus, producing elevated levels of testosterone
B) anterior pituitary, producing elevated levels of testosterone
C) testes, producing elevated levels of estrogen
D) anterior pituitary, producing elevated levels of gonadotropin-stimulating hormone
Answer: D

Answer 108

D) anterior pituitary, producing elevated levels of gonadotropin-stimulating hormone

Question 109

Which statement about human reproduction is correct?
A) Fertilization occurs in the uterus.
B) In humans, spermatogenesis and oogenesis function best at normal, core body temperatures.
C) A human oocyte completes meiosis after a sperm penetrates it.
D) The earliest stages of spermatogenesis occur closest to the lumen of the seminiferous tubules.

Answer 109

C) A human oocyte completes meiosis after a sperm penetrates it.

Question 110

For which of the following is the number the same in spermatogenesis and oogenesis?
A) timing of meiotic divisions
B) functional gametes produced by meiosis
C) meiotic divisions required to produce each gamete
D) different cell types produced by meiosis

Answer 110

C) meiotic divisions required to produce each gamete

Question 111

The surgical removal of the seminal vesicles would likely _____.
A) cause sterility because sperm would not be produced
B) cause sterility because sperm would not be able to exit the body
C) greatly reduce the volume of semen
D) cause the testes to migrate back into the abdominal cavity

Answer 111

C) greatly reduce the volume of semen

Question 112

Human sperm cells first arise in the \_\_\_\_\_.
A) prostate gland
B) vas deferens
C) seminiferous tubules
D) epididymis

Answer 112

C) seminiferous tubules

Question 113

Among human males, both semen and urine normally travel along the \_\_\_\_\_.
A) vas deferens
B) seminal vesicle
C) urethra
D) ureter

Answer 113

C) urethra

Question 114

Among mammals, the male and female genital structures that consist mostly of erectile tissue include the \_\_\_\_\_.
A) penis and clitoris
B) vas deferens and oviduct
C) testes and ovaries
D) prostate and ovaries

Answer 114

A) penis and clitoris

Question 115

Which of the following correctly describes a difference between spermatogenesis and oogenesis?
A) Spermatogenesis results in four mature sperm cells, while oogenesis results in one mature egg cell.
B) Spermatogenesis results in one mature sperm cell, while oogenesis results in four mature egg cells.
C) In spermatogenesis, mitosis occurs twice and meiosis once, while in oogenesis, mitosis occurs once and meiosis twice.
D) Spermatogenesis results in four mature sperm cells, while oogenesis results in one mature egg cell. In spermatogenesis, mitosis occurs twice and meiosis once, while in oogenesis, mitosis occurs once and meiosis twice.

Answer 115

A) Spermatogenesis results in four mature sperm cells, while oogenesis results in one mature egg cell.

Question 116

Mature human sperm and ova are similar in that they _____.
A) both have the same number of chromosomes
B) are approximately the same size
C) each have a flagellum that provides motility
D) are produced from puberty until death

Answer 116

A) both have the same number of chromosomes

Question 117

In vertebrate animals, spermatogenesis and oogenesis differ in that _____.
A) oogenesis begins at the onset of sexual maturity, whereas spermatogenesis begins during embryonic development
B) oogenesis produces four functional haploid cells, whereas spermatogenesis produces only one functional spermatozoon
C) cytokinesis is unequal in oogenesis, whereas it is equal in spermatogenesis
D) oogenesis ends at menopause, whereas spermatogenesis is finished before birth

Answer 117

C) cytokinesis is unequal in oogenesis, whereas it is equal in spermatogenesis

Question 118

At the time of fertilization, the maturation of the human oogonium has resulted in \_\_\_\_\_.
A) one secondary oocyte
B) two primary oocytes
C) four secondary oocytes
D) four zygotes

Answer 118

A) one secondary oocyte

Question 119

In humans, the follicular cells that remain behind in the ovary following ovulation become _____.
A) the ovarian endometrium that is shed at the time of the menses
B) a steroid-hormone synthesizing structure called the corpus luteum
C) the thickened portion of the uterine wall
D) the placenta, which secretes cervical mucus

Answer 119

B) a steroid-hormone synthesizing structure called the corpus luteum

Question 120

Which of the following structures in females is analogous in function to the vas deferens in males?
A) urethra
B) oviduct
C) uterus
D) vagina

Answer 120

B) oviduct

Question 121

Which of the following is a challenge to the hypothesis that bats, which produce an unusually large number of sperm, increase the probability of conception when females engage in multiple matings?
I) Female bats can eject the sperm of certain males after mating.
II) A female can actively choose which male mates with her last, thus increasing the odds of conception with that male’s sperm.
A) Only I is correct.
B) Only II is correct.
C) Both I and II are correct.

Answer 121

C) Both I and II are correct.

Question 122

You decide to study two species of birds, both of which form monogamous pairs (one male and one female). In species 1, you find that the eggs in a pair’s nest are in fact almost always the offspring of that pair. In species 2, you are surprised to find that many of the eggs in a nest were actually fathered by males of neighboring pairs. Apparently, mating outside of monogamous pairings is widespread in species 2. Given this information, what would be the logical prediction to make before comparing testes size of males of the two species?
A) Testes of species 1 are larger than testes of species 2.
B) Testes of species 2 are larger than testes of species 1.
C) There is no relationship between this observation and the size of testes.

Answer 122

B) Testes of species 2 are larger than testes of species 1.

Question 123

In close comparisons, external fertilization often yields more offspring than does internal fertilization. However, internal fertilization typically offers the advantage that _____.
A) it requires less time and energy to be devoted to reproduction
B) the smaller number of offspring produced often receive a greater amount of parental investment
C) it permits the most rapid population increase
D) it requires expression of fewer genes and maximizes genetic stability

Answer 123

B) the smaller number of offspring produced often receive a greater amount of parental investment

Question 124

Animals that have external fertilization are most likely to reproduce in which of the following areas?
A) sand dune
B) polar ice sheet
C) shallow lake
D) tallgrass prairie

Answer 124

C) shallow lake

Question 125

Females of many insect species, including honeybee queens, can store gametes shed by their mating partners in \_\_\_\_\_.
A) their nests
B) the abdominal tract
C) the uterus
D) the spermatheca

Answer 125

D) the spermatheca

Question 126

Among non-mammalian vertebrates, the cloaca is an anatomical structure that functions as _____.
A) a specialized sperm-transfer device produced only by males
B) a shared pathway for the digestive, excretory, and reproductive systems
C) a source of nutrients for developing sperm in the testes
D) a gland that secretes mucus to lubricate the vaginal opening

Answer 126

B) a shared pathway for the digestive, excretory, and reproductive systems

Question 127

For water fleas of the genus Daphnia, switching from a pattern of asexual reproduction to sexual reproduction coincides with _____.
A) environmental conditions becoming more favorable for offspring
B) greater abundance of food resources for offspring
C) periods of temperature or food stresses on adults
D) exhaustion of an individual’s supply of eggs

Answer 127

C) periods of temperature or food stresses on adults

Question 128

Asexual reproduction results in greater reproductive success than does sexual reproduction when _____.
A) pathogens are rapidly diversifying
B) there is some potential for rapid overpopulation
C) a species is expanding into diverse geographic settings
D) a species is in stable and favorable environments

Answer 128

D) a species is in stable and favorable environments

Question 129

Genetic mutations in asexually reproducing organisms lead to more evolutionary change than do genetic mutations in sexually reproducing ones because _____.
A) asexually reproducing organisms, but not sexually reproducing organisms, pass all mutations on to their offspring
B) sexually reproducing organisms can produce more offspring in a given time than can asexually reproducing organisms
C) more genetic variation is present in organisms that reproduce asexually than is present in those that reproduce sexually
D) asexually reproducing organisms have more dominant genes than organisms that reproduce sexually

Answer 129

A) asexually reproducing organisms, but not sexually reproducing organisms, pass all mutations on to their offspring

Question 130

In an animal that switches between sexual and asexual reproduction, when is sexual reproduction more likely to occur?
A) when conditions for survival are favorable
B) when conditions for survival are unfavorable
C) when males and females find each other
D) What conditions favor sexual over asexual remains a complete mystery.

Answer 130

B) when conditions for survival are unfavorable

Question 131

Evidence that parthenogenic whiptail lizards are derived from sexually reproducing ancestors includes _____.
A) the requirement for male-like behaviors in some females before their partners will ovulate
B) the development and then regression of testes prior to sexual maturation
C) the observation that all of the offspring are haploid
D) the persistence of a vestigial penis among some of the females

Answer 131

A) the requirement for male-like behaviors in some females before their partners will ovulate

Question 132

Environmental cues that influence the timing of reproduction generally do so by _____.
A) increasing the body temperature
B) providing access to water for external fertilization
C) increasing ambient temperature most favorable for sex
D) direct effects on hormonal control mechanisms

Answer 132

D) direct effects on hormonal control mechanisms

Question 133

Which of the following is most true of sexual reproduction?
A) Only half of the offspring from sexually reproducing females are also females.
B) Asexual reproduction produces offspring of greater genetic variety.
C) Sexual reproduction is completed more rapidly than asexual reproduction.
D) Asexual reproduction is better suited to environments with extremely varying conditions.

Answer 133

A) Only half of the offspring from sexually reproducing females are also females.

Question 134

On a submarine expedition to the ocean bottom, you discover a population of fish that are only female. What type of reproduction does this fish most likely use?
A) sexual
B) budding
C) cloning
D) parthenogenesis

Answer 134

D) parthenogenesis

Question 135

Which of the following aspects of eukaryotic reproduction are found only among invertebrate animals?
A) sexual and asexual reproduction
B) external and internal fertilization
C) hermaphroditism and parthenogenesis
D) fission and budding

Answer 135

D) fission and budding

Question 136

Asexual reproduction results in offspring that are genetically identical to their parent. What type of cell process occurs to generate this type of offspring?
A) mitosis
B) meiosis
C) cell fusion

Answer 136

A) mitosis

Question 137

Regeneration, the regrowth of lost body parts, normally follows \_\_\_\_\_.
A) all types of asexual reproduction
B) fission
C) fragmentation
D) parthenogenesis

Answer 137

C) fragmentation