Question 1

Which of the following would increase the rate of oxygen diffusion from the air into the body cells of a flatworm?

Accepted Answer

Increasing the surface area of the body enhances the rate of oxygen diffusion by providing a larger area for gas exchange, which is crucial for organisms like flatworms that rely on diffusion across their body surface for oxygen uptake.

Question 2

What are desirable characteristics for a gas exchange surface, such as the endothelial cells lining the inside of lung?

Accepted Answer

A large surface area allows for more gas exchange to occur, while a thin surface (under 10 micrometers) allows for gases to diffuse across quickly. A small surface area (choice B) would limit gas exchange, and a thickness of 100 micrometers (choice C) would be too thick for efficient diffusion of gases.

Question 3

Which of the following statements is FALSE?

Accepted Answer

Ventilation can involve mechanisms that do not necessarily require a pump to generate pressure. For example, in humans, ventilation occurs through the movement of the diaphragm and rib muscles, creating a pressure difference that allows air to flow into the lungs. This process does not involve a pump in the same way the heart acts as a pump for circulation.

Question 4

Which of the following is the CORRECT order of steps of gas transport and exchange?

Accepted Answer

The correct order of gas transport and exchange starts with ventilation, where air is pulled into the lungs through inhalation and pushed out through exhalation. This is followed by diffusion across the respiratory surface, where oxygen (O2) crosses the respiratory membrane from the air into the blood vessels, and carbon dioxide (CO2) diffuses from the capillaries into the alveoli. Then, circulation takes place, where the O2-rich blood is carried from the lungs to the body tissues and organs, while at the same time the CO2-rich blood is transported from the body tissues and organs back to the lungs. Finally, diffusion between blood and cells occurs, where O2 diffuses from the blood into the cells, while CO2 diffuses from the cells into the blood for transport back to the lungs.

Question 5

One of the functions of the respiratory system is to rid the body of CO₂. Where does the CO₂ come from?

Accepted Answer

CO₂ is a byproduct of cellular respiration, which breaks down carbohydrates and lipids to release energy. As part of this process, CO₂ is produced and removed from the body through the respiratory system.

Question 6

A constant supply of oxygen is essential to animal survival. Why?

Accepted Answer

The answer of A constant supply of oxygen is essential...

Question 7

Which of the following affect the rate of diffusion of a substance?

Accepted Answer

The answer of Which of the following affect the rate...

Question 8

Simple multicellular organisms that are small can meet their gas exchange needs by means of:

Accepted Answer

The answer of Simple multicellular organisms that are small can...

Question 9

Organisms that use bulk flow to move oxygen are able to:

Accepted Answer

Bulk flow allows organisms to transport oxygen and other substances over greater distances efficiently, supporting larger body sizes compared to reliance solely on diffusion.

Question 10

Which of the following is an example of bulk flow during gas exchange in vertebrates?

Accepted Answer

Bulk flow refers to the movement of a fluid (liquid or gas) in bulk, typically driven by pressure differences. In vertebrates, the movement of water or air past a respiratory surface (such as gills or lungs) is an example of bulk flow, as it involves the movement of large volumes of fluid.

Question 11

Diffusion is an effective way to exchange gases over short distances, but not over large distances.

Accepted Answer

Diffusion is effective over short distances because it relies on the random movement of molecules. Over large distances, the concentration gradient is reduced, and diffusion becomes less efficient. In organisms, specialized structures such as respiratory systems and circulation help facilitate the exchange of gases over larger distances.

Question 12

If the partial pressure of oxygen outside of a cell is 100 mmHg and the partial pressure of oxygen inside of a cell is 25 mmHg, which of the following statements is CORRECT?

Accepted Answer

When there is a difference in partial pressure of a gas across a membrane, there will be a net movement of that gas from the area of higher partial pressure to the area of lower partial pressure until equilibrium is reached. In this case, the partial pressure of oxygen is higher outside of the cell than inside, so oxygen will move from outside the cell to inside the cell.

Question 13

The partial pressure of a gas is:

Accepted Answer

The partial pressure of a gas is the fraction of the total pressure contributed by that gas. It is calculated by multiplying the fractional concentration of the gas by the overall atmospheric pressure. This is known as Dalton's Law of Partial Pressures.

Question 14

The respiratory and cardiovascular systems of vertebrate animals work in tandem to transport oxygen to metabolizing tissues and to eliminate carbon dioxide as a waste gas. Which of the following statements accurately describes how these systems interact for gas exchange?

Accepted Answer

The rate of oxygen transport by diffusion across the lungs must generally match the rate of transport by the circulatory system to ensure efficient gas exchange. Bulk flow is effective over long distances, while diffusion is effective over short distances.

Question 15

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?

Accepted Answer

The partial pressure of a gas in a mixture is calculated by multiplying the total pressure of the mixture by the fraction of the gas in the mixture. For oxygen, with 10% of the atmosphere, its partial pressure would be 0.10 * 760 mmHg = 76 mmHg.

Question 16

One of the functions of the respiratory system is to rid the body of CO₂. What is the specific biochemical pathway that is responsible for CO₂ production?

Accepted Answer

The answer of One of the functions of the respiratory...

Question 17

_____ is the process by which molecules of a substance move from regions of high concentration to regions of low concentration (until an equilibrium is reached).

Accepted Answer

The answer of _____ is the process by which molecules...

Question 18

We breathe more quickly and deeply when we exercise. Why does this make sense?

Accepted Answer

When we exercise, our muscles require more ATP for energy, which is produced through aerobic respiration that requires more oxygen (B). Additionally, exercise increases CO2 production as a byproduct of metabolism, and increased ventilation helps expel this excess CO2 (D).

Question 19

Which of the following would INCREASE the rate of flow in blood vessels?

Accepted Answer

Increasing the diameter of blood vessels (vasodilation) and decreasing their length (by smoothing out any kinks or curves) will decrease resistance to blood flow, allowing for a faster rate of flow. Decreasing the diameter of blood vessels or increasing their length will increase resistance to blood flow, slowing down the rate of flow.

Question 20

Lamellae are structures that are present in the:

Accepted Answer

Lamellae are structures present in the gills of fish. They increase the surface area for gas exchange to occur. The other options are incorrect as they do not have lamellae structures.

Quiz 39: Animal Cardiovascular and Respiratory Systems