Ch 37: Animal Cardiovascular and Respiratory Systems

Question 1

Imagine a planet that has a similar atmospheric pressure to Earth (760 mmHg) but different concentrations of gases in its atmosphere. On this hypothetical planet, oxygen makes up 10% of the atmosphere, carbon dioxide makes up 15%, and nitrogen makes up the remaining 75%. Based on this information, what is the partial pressure of oxygen on this new planet?

Answer 1

76 mmHg

Question 2

What is the main benefit of having hemoglobin in the blood?

Answer 2

It increases the amount of oxygen that can be carried in the blood.

Question 3

What function do collagen and elastin have in arteries?

Answer 3

They provide elastic rebound of the arterial wall to help smooth out blood flow.

Question 4

What is the correct order of events in the control of the heartbeat?
1 - activation of the SA node
2 - contraction of the atria
3 - contraction of the ventricles
4 - activation of the AV node
5 - transmission of the action potential through a set of modified conducting muscle fibers

Answer 4

1, 2, 4, 5, 3

Question 5

T/F: The unidirectional flow of air through a bird’s lungs maintains a larger concentration gradient for diffusion than can be obtained through tidal breathing.

Answer 5

True

Question 6

T/F: Myoglobin is found within vertebrate muscle cells.

Answer 6

Ture

Question 7

T/F: Imagine that a doctor encounters a patient carrying a mutation that reduces collagen production. As a result, the arteries of this patient will likely be stronger and more resistant to aneurysms compared to arteries in an individual not carrying this mutation.

Answer 7

False

Question 8

T/F: Diving reptiles can alter the pattern of blood circulation to bypass their lungs when submerged.

Answer 8

True

Question 9

T/F: The blood pressure within the veins is much lower than the blood pressure within the arteries.

Answer 9

True

Question 10

T/F: The repolarization of the pacemaker cells following an action potential allows the heart to relax between contractions.

Answer 10

True

Question 11

When stimulated by _____, arterioles supplying the digestive system ______, which decreases blood flow to digestive organs.

Answer 11

sympathetic nerves; constrict

Question 12

At any given point along the length of the gill lamella, how does the pO2 of the blood flowing through the blood vessels in the lamella compare to the pO2 of the water flowing over the gill lamella?

Answer 12

The pO2 of the blood is lower than the pO2 of the water.

Question 13

A scientist is evaluating the hemoglobin in mountain goats compared to the hemoglobin in normal barnyard goats. How will the hemoglobin in these two goat species compare?

Answer 13

Given that mountain goats tend to live at higher altitudes, these goats will have hemoglobin with a greater oxygen-binding affinity compared to the hemoglobin of barnyard goats.

Question 14

At the venous end of a capillary, the blood pressure is _____ the osmotic pressure and fluid _____ the blood vessel.

Answer 14

lower than; moves into

Question 15

T/F: Diffusion is an effective way to exchange gases over short distances but not over large distances.

Answer 15

True

Question 16

What is the function of surfactant in the mammalian respiratory system?

Answer 16

reduction of surface tension in the fluid covering the alveoli

Question 17

T/F: If a hemoglobin molecule comes into close contact with a respiring cell, the presence of CO2 in the environment will cause hemoglobin to bind to more oxygen molecules (if it is not already bound to four).

Answer 17

False

Question 18

How many molecules of O2 can a single hemoglobin molecule carry when fully saturated?

Answer 18

4

Question 19

Why do cells in the airways of the lungs produce mucus?

Answer 19

to trap pathogens and guard against infection

Question 20

How is a fetus able to extract O2 from its mother’s blood?

Answer 20

Fetal hemoglobin has a higher affinity for O2 than maternal hemoglobin.

Question 21

What is meant by tidal ventilation?

Answer 21

Air moves into the lungs during inhalation and air moves out of the lungs during exhalation.

Question 22

What percentage of oxygen in the air is typically extracted by the mammalian lung when an animal is resting?

Answer 22

less than 25%

Question 23

The partial pressure of one gas in a mixture is:

Answer 23

its fractional contribution to total pressure of the mixture.

Question 24

T/F: As you read this sentence, you have breathed in and out. What you have just experienced is referred to as “gas exchange,” where you have taken oxygen into your lungs and expelled carbon dioxide into the environment.

Answer 24

True