$C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{Heat}$

Question 1

Which of the following best describes why animals must ingest essential nutrients throughout their lives?

Accepted Answer

Essential nutrients are molecules that animals cannot synthesize themselves and are necessary for normal physiological function.

Question 2

Which of the following is NOT a fundamental reason animals need energy?

Accepted Answer

To store genetic information in DNA.

Question 3

An animal's metabolic rate is best defined as:

Accepted Answer

The total amount of energy an animal converts to heat per unit time.

Question 4

Which of the following equations correctly represents the aerobic respiration of glucose in animals?

Accepted Answer

$C_6H_{12}O_6 + 6O_2 ightarrow 6CO_2 + 6H_2O + 	ext{Heat}$

Question 5

Which of the following best explains why small mammals like mice have higher metabolic rates per gram than large mammals like elephants?

Accepted Answer

Small mammals lose heat more rapidly due to a higher surface area-to-volume ratio, requiring more energy to maintain body temperature.

Question 6

Which of the following is an example of 'division of labor' in animal tissues?

Accepted Answer

Specialized cells in the digestive tract absorbing nutrients while others secrete digestive enzymes.

Question 7

Which of the following best describes the role of epithelial tissue in the digestive system?

Accepted Answer

It covers surfaces and lines organs, facilitating absorption and compartmentalization.

Question 8

A patient is unable to absorb fats efficiently. Which part of their digestive system is most likely malfunctioning?

Accepted Answer

The midgut (small intestine), where most nutrient absorption takes place.

Question 9

Which of the following statements about peristalsis is correct?

Accepted Answer

Peristalsis is the rhythmic contraction of muscles that propels food through the digestive tract.

Question 10

Which of the following best explains why herbivores like cows have longer intestines compared to carnivores?

Accepted Answer

Herbivores need more time and surface area to digest and absorb nutrients from plant material, which is harder to break down.

Question 11

Which of the following is a correct statement about essential amino acids in humans?

Accepted Answer

There are 8 essential amino acids that humans must obtain from their diet.

Question 12

A scientist measures the oxygen consumption of a resting animal to estimate its metabolic rate. Which principle justifies this method?

Accepted Answer

Oxygen consumption is directly proportional to the rate of heat production during aerobic metabolism.

Question 13

Which of the following is a real-world example of symbiotic relationships aiding digestion in animals?

Accepted Answer

Cows rely on gut microbes to digest cellulose in plant material.

Question 14

If an animal's metabolic rate increases during exercise, which of the following is most likely to occur?

Accepted Answer

The animal's rate of heat production increases.

Question 15

Which of the following best explains why frogs feel cold to the touch compared to mammals?

Accepted Answer

Frogs have a lower metabolic rate and lose heat more rapidly to the environment.

Question 16

Which of the following is a correct application of the concept of 'division of labor' in a multicellular animal?

Accepted Answer

Muscle cells contract to move food, while epithelial cells absorb nutrients.

Question 17

Which of the following is a correct statement about the relationship between diet and digestive tract length?

Accepted Answer

Herbivores have longer intestines to allow more time and surface area for digesting plant material.

Question 18

Which of the following best describes the function of villi in the small intestine?

Accepted Answer

They increase the surface area for absorption of nutrients.

Question 19

A mutation causes an animal to lack the ability to form epithelial tissue. Which of the following would be a likely consequence?

Accepted Answer

The animal would be unable to absorb nutrients efficiently.

Question 20

Which of the following best explains why measuring the rate of carbon dioxide production can be used to estimate metabolic rate?

Accepted Answer

Carbon dioxide is produced as a byproduct of aerobic respiration, which is proportional to energy usage.

Digestive Systems in Animals: Structure, Function, and Integration

Study Guide - Practice Questions