Animal Bio

Question 1

In mammals, most gas exchange between the atmosphere and the pulmonary blood occurs in the
(A) bronchi.
(B) trachea.
(C) larynx.
(D) bronchioles.
(E) alveoli.

Answer 1

(E) alveoli

Question 2

Most of the carbon dioxide produced by humans is

(A) converted to bicarbonate ions by an enzyme in red blood cells
(B) bound to hemoglobin
(C) transported in the erythrocytes as carbonic acid
(D) simply dissolved in plasma
(E) bicarbonate ions bound to hemoglobin

Answer 2

(A) converted to bicarbonate ions by an enzyme in red blood cells

Question 3

If a molecule of CO2 released into the blood in your left toe is exhaled from your nose, it must pass through all of the following except

(A) the trachea
(B) the right atrium
(C) an alveolus
(D) the pulmonary vein
(E) the right ventricle

Answer 3

(D) the pulmonary vein

Question 4

Which of the following mechanisms are used to regulate blood pressure in the closed circulatory system of vertebrates?
I) changing the force of heart contraction
II) constricting and relaxing sphincters in the walls of arterioles
III) adjusting the volume of blood contained in the veins
IV) synthesizing new capillaries

(A) only I and II
(B) only I and III
(C) only II and III
(D) I, II, and III
(E) I, II, and IV

Answer 4

(D) I, II, and III

Question 5

How does the design of the circulatory network contribute to reducing blood pressure in the capillary beds avoid hemorrhage?

(A) Blood flow through the capillaries is essentially frictionless, and this reduces the amount of pressure on their walls.
(B) The total cross-sectional diameter of the arterial circulation increases with progression from artery to arteriole to capillary, leading to a reduced blood pressure.
(C) Fluid loss from the arteries is high enough that pressure drops off significantly by the time blood reaches the capillaries.
(D) Capillary beds have the thickest walls of any blood vessel to resist these high pressures.
(E) Capillaries are always open to ensure adequate space for blood to flow into

Answer 5

B) The total cross-sectional diameter of the arterial circulation increases with progression from artery to arteriole to capillary, leading to a reduced blood pressure

Question 6

The material present in arterioles that is not present in capillaries is
(A) a lining of endothelial cells.
(B) white blood cells and platelets.
(C) fully oxygenated blood.
(D) circular smooth muscle cells that can alter the size of the arterioles.
(E) plasma in which carbon dioxide has been added.

Answer 6

(D) circular smooth muscle cells that can alter the size of the arterioles

Question 7

Hydrogen ions produced within human red blood cells are prevented from significantly lowering plasma pH because they bind to

(A) hemoglobin
(B) plasma proteins
(C) carbon dioxide
(D) carbonic acid
(E) plasma buffers

Answer 7

(A) hemoglobin

Question 8

Damage to the sinoatrial node in humans

(A) would block conductance between the bundle branches and the Purkinje fibers
(B) would have a negative effect on peripheral resistance
(C) would disrupt the rate and timing of cardiac muscle contractions
(D) would have a direct effect on blood pressure monitors in the aorta
(E) is a major contributor to heart attacks

Answer 8

(C) would disrupt the rate and timing of cardiac muscle contractions

Question 9

The plasma proteins in humans

(A) carry out gas exchange.
(B) maintain the blood’s osmotic pressure.
(C) undergo aerobic metabolism.
(D) transport oxygen.
(E) transport water-soluble lipids.

Answer 9

(B) maintain the blood’s osmotic pressure

Question 10

Salivary amylase digests

(A) monosaccharides
(B) starches
(C) maltose
(D) protein
(E) glucose

Answer 10

(B) starches

Question 11

Ingested dietary substances must cross cell membranes to be used by the body, a process known as

(A) digestion
(B) ingestion
(C) elimination
(D) absorption
(E) hydrolysis

Answer 11

(D) absorption

Question 12

The “motor unit” in vertebrate skeletal muscle refers to

(A) one motor neuron and all of the muscle fibres on which it has synapses.
(B) one sarcomere and all of its actin and myosin filaments.
(C) an entire muscle.
(D) one myofibril and all of its sarcomeres.
(E) one actin binding site and its myosin partner.

Answer 12

(A) one motor neuron and all of the muscle fibres on which it synapses

Question 13

The hydrostatic skeleton of the earthworm allows it to move around in its environment by

(A) walking on its limbs
(B) swimming with its setae
(C) using peristaltic contractions of its circular and longitudinal muscles
(D) alternating contractions and relaxations of its flagella
(E) crawling with its feet

Answer 13

(C) using peristaltic contractions of its circular and longitudinal muscles

Question 14

Who might be interested in using cytokinins?

(A) grocers, to spray on fruit to enhance ripening in the store
(B) consumers, to spray on fruit before eating to enhance taste
(C) florists, to dip stems in to keep leaves green longer
(D) farmers, to spray on fruit after picking to stall ripening

Answer 14

(C) florist, to dip stems in to keep leaves green longer

Question 15

Which of the following plant hormones are most likely to act synergistically if expressed or applied to a drought-stricken plant?

(A) auxin and ethylene
(B) phytochrome and gibberellins
(C) gibberellins and abscisic acid
(D) abscisic acid and ethylene
(E) brassinosteroids and cytokinins

Answer 15

(D) abscisic acid and ethylene

Question 16

The vegetative (nutritionally active) bodies of most fungi are

(A) referred to as a mycelium
(B) usually underground
(C) composed of hyphae
(D) three of these responses are correct
(E) two of these responses are correct

Answer 16

(D) three of these responses are correct

Question 17

Lichens are symbiotic associations of fungi and

(A) green algae
(B) mosses
(C) cyanobacteria
(D) three of these responses are correct
(E) two of these responses are correct

Answer 17

(E) two of these responses are correct
Green algae and Cyanobacteria

Question 18

Cells produced by lateral meristems are known as

(A) dermal and ground tissue
(B) lateral tissues
(C) pith
(D) secondary tissues
(E) shoots and roots

Answer 18

(D) secondary tissues

Question 19

Guard cells do which of the following?
(A) protect the endodermis
(B) accumulate K+ and close the stomata
(C) contain chloroplasts that import K+ directly into the cells
(D) guard against mineral loss through the stomata
(E) help balance the photosynthesis-transpiration compromise

Answer 19

(E) help balance the photosynthesis-transpiration compromise

Question 20

The velocity of blood flow is the lowest in capillaries because

(A) the capillary walls are not thin enough to allow oxygen to exchange with the cells
(B) the capillaries are far from the heart, and blood flow slows as distance from the heart increases
(C) the diastolic blood pressure is too low to deliver blood to the capillaries at a high flow rate
(D) the systemic capillaries are supplied by the left ventricle, which has a lower cardiac output than the right ventricle
(E) the total cross-sectional area of the capillaries is greater than the total cross-sectional area of the arteries or any other part of the circulatory system

Answer 20

(E) the total cross-sectional area of the capillaries is greater than the total cross-sectional area of the arteries or any other part of the circulatory system

Question 21

o become bound to hemoglobin for transport in a mammal, atmospheric molecules of oxygen must cross
(A) zero membranes, oxygen binds directly to hemoglobin, a protein dissolved in the (plasma of the blood.
(B) one membrane, that of the lining in the lungs and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood.
(C) two membranes, in and out of the cell lining the lung — and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood.
(D) four membranes, in and out of the cell lining the lung, in and out of the endothelial cell lining the pulmonary capillary — and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood.
(E) five membranes, in and out of the cell lining the lung, in and out of the endothelial cell lining the pulmonary capillary, and into the red blood cell to bind with hemoglobin.

Answer 21

(E) five membranes, in and out of the cell lining the lung, in and out of the endothelial cell lining the pulmonary capillary, and into the red blood cell to bind with hemoglobin.

Question 22

A human red blood cell in an artery of the left arm is on its way to deliver oxygen to a cell in the thumb. To travel from the artery in the arm to the left ventricle, this red blood cell must pass through

(A) Five
(B) One
(C) Four
(D) Three
(E) Two

Answer 22

(E) Two

Question 23

Among the following choices, which organism likely has the highest systolic pressure?

(A) mouse
(B) rabbit
(C) human
(D) hippopotamus
(E) giraffe

Answer 23

(E) giraffe

Question 24

The semilunar valves of the mammalian heart

(A) are found only on the right side of the heart
(B) prevent backflow of blood in the aorta and pulmonary arteries
(C) are the route by which blood flows from atria to the ventricles
(D) are the attachment site where the pulmonary veins empty into the heart
(E) are at the places where the anterior and posterior venae cavae empty into the heart

Answer 24

(B) prevent backflow of blood in the aorta and pulmonary arteries

Question 25

Connective tissues typically have

a) the ability to transmit electrochemical impulses
b) the ability to shorten upon stimulation
c) many densely packed cells with direct connections between the membranes of adjacent cells
d) a supporting material such as chondroitin
e) relatively few cells and a large amount of extracellular matrix

Answer 25

e) relatively few cells and a large amount of extracellular matrix

Question 26

It is wintertime and your pet lizard has somehow escaped into the backyard. After much searching, you find him basking on a rock in the sun trying to keep warm.

To conserve heat, it is likely that

a) the lizard will utilize countercurrent exchange
b) blood vessels in the extremities are dilated
c) blood vessels in the extremities are constricted
d) the lizard will become a temperature conformer
e) blood pressure has decreased in the extremities

Answer 26

c) blood pressure has decreased in the extremities

Question 27

Analysis of a blood sample from a fasting individual who had not eaten for 24 hours would be expected to reveal high levels of

a) secretin
b) insulin
c) glucose
d) glucagon
e) gastrin

Answer 27

d) glucagon

Question 28

Hormones that promote homeostasis

a) utilize receptors that bind any hormone
b) usually operate as part of a negative feedback loop
c) are not found as members of antagonistic signaling mechanisms
d) travel to target cells without passage in the plasma
e) initiate signal transduction in the target cell without binding to receptors

Answer 28

B) usually operate as part of a negative feedback loop

Question 29

Even in the absence of sperm, metabolic activity in an egg can be artificially activated by

a) abnormally low levels of extracellular oxygen
b) injection of calcium ions into the cytosol
c) abnormally high levels of carbonic acid in the cytosol
d) exposure to the low pH of the uterus
e) depletion of its ATP supplies

Answer 29

b) injection of calcium ions into the cytosol

Question 30

A human blastomere is

a) a component of the zona pellucida
b) that part of the acrosome that opens the egg’s membrane
c) an embryonic structure that includes a fluid-filled cavity
d) an embryonic cell that is much smaller than the ovum
e) a cell that contains a (degenerating) second polar body

Answer 30

an embryonic cell that is much smaller than the ovum

Question 31

In placental mammals, the yolk sac

a) transfers nutrients from yolk to embryo
b) differentiates into the placenta
c) becomes a fluid-filled sac that surrounds and protects the embryo
d) stores waste products from embryo until the placenta develops
e) produces blood cells that then migrate into the embryo

Answer 31

e) produces blood cells that then migrate into the embryo

Question 32

If gastrulation were blocked by an environmental toxin, then

a) cleavage would not occur in the zygote
b) fertilization would be blocked
c) the blastula would not be formed
d) the blastopore would form above the grey crescent in the animal pole
e) embryonic germ layers would not form

Answer 32

e) embryonic germ layers would not form

Question 33

In a developing frog embryo, most of the yolk is

a) distributed equally throughout the embryo
b) found within the blastocoels
c) located near the animal pole
d) located near the vegetal pole
e) found within the cleavage furrow

Answer 33

d) located near the vegetal pole

Question 34

Inflammatory responses typically include

a) reduced permeability of blood vessels to conserve plasma.
b) clotting proteins migrating away from the site of infection.
c) inhibiting the release of white blood cells from bone marrow.
d) release of substances to decrease the blood supply to an inflamed area.
e) increased activity of phagocytes in an inflamed area.

Answer 34

e) increased activity of phagocytes in an inflamed area

Question 35

The transfer of fluid from the glomerulus to Bowman’s capsule

a) is very selective as to which subprotein-sized molecules are transferred
b) usually includes the transfer of red blood cells into Bowman’s capsule
c) transfers large molecules as easily as small ones
d) is mainly a consequence of blood pressure in the capillaries of the glomerulus
e) results from active transport

Answer 35

d) is mainly a consequence of blood pressure in the capillaries of the glomerulus

Question 36

Which of the following reactions prevails in red blood cells traveling through alveolar capillaries? (Hb = hemoglobin)

a) Hb + 4 O2 → Hb(O2)4
b) Hb(O2)4 → Hb + 4 O2
c) CO2 + H2O → H2CO3
d) H2CO3 → H+ + HCO3
e) Hb + 4 CO2 → Hb(CO2)4

Answer 36

a) Hb + 4 O2 → Hb(O2)4

Question 37

Endocrine structures derived from nervous tissue include the

a) ovaries and the testes
b) thymus and the thyroid
c) posterior pituitary gland and the adrenal medulla
d) anterior pituitary gland and the adrenal cortex
e) liver and pancreas

Answer 37

c) posterior pituitary gland and the adrenal medulla

Question 38

In mammals, the nuclei resulting from the union of the sperm and the egg are first truly diploid at the end of the

a) complete of spermatogenesis
b) completion of gastrulation
c) acrosomal reaction
d) initial cleavage
e) activation of the egg

Answer 38

d) initial cleavage

Question 39

Cortical reaction functions directly in the

a) fusion of egg and sperm nuclei
b) formation of a fertilization envelope
c) generation of a nerve-like impulse by the egg cell
d) release of hydrolytic enzymes from the sperm cell
e) production of a fast block polyspermy

Answer 39

b) formation of a fertilization envelope