Question 1

Which statement best describes why mechanical digestion, the process of breaking down large chunks of food into smaller pieces, is an important digestive process?

Accepted Answer

Mechanical digestion increases the surface area of food, which enhances the efficiency of chemical digestion by providing more area for digestive enzymes to act upon. This process is crucial for the efficient breakdown and absorption of nutrients.

Question 2

It is important for pregnant women to consume folic acid supplements because ________.

Accepted Answer

Folic acid is crucial for the proper development of the neural tube in a fetus, and its deficiency can lead to neural tube defects such as spina bifida and anencephaly.

Question 3

Which of the following is an advantage of a complete digestive system?

Accepted Answer

A complete digestive system, unlike a simple one, allows for the development of specialized regions (such as the stomach, intestines, etc.) that can perform specific functions in the process of digestion, improving efficiency and nutrient absorption.

Question 4

Examine the digestive system structures in the figure. In which labeled structure is the rate of nutrient absorption the highest?

Accepted Answer

The answer of  Examine the digestive system structures in...

Question 5

Lysine is an essential amino acid for animals. An animal that lacked lysine in its diet ________.

Accepted Answer

Lysine is an essential amino acid, meaning animals cannot synthesize it and must obtain it from their diet. Without lysine, an animal would be unable to produce many proteins that are crucial for various bodily functions, leading to health issues.

Question 6

Which process does the large surface area in the intestine make more efficient?

Accepted Answer

The large surface area in the intestine makes absorption more efficient because it provides more space for nutrients to be absorbed from food.

Question 7

The process by which digested dietary substances cross cell membranes to be used by the body is known as ________.

Accepted Answer

The process by which digested dietary substances cross cell membranes to be used by the body is known as absorption.

Question 8

Iodine deficiency in mammals will most likely result in ________.

Accepted Answer

Iodine is crucial for the synthesis of thyroid hormones. A deficiency in iodine leads to decreased production of these hormones, which can result in various health issues, including goiter and hypothyroidism.

Question 9

Which of the following is a difference between vitamins and minerals?

Accepted Answer

Vitamins are organic compounds that are essential in small quantities for our bodies to function properly, whereas minerals are inorganic elements that also play crucial roles in bodily functions. This fundamental difference in their chemical nature (organic vs. inorganic) is a key distinction between vitamins and minerals.

Question 10

Each of three groups of cyclists had a different diet: high-carbohydrate; a mix of carbohydrates, fat, and protein; or high in protein and fat. The blood glucose levels of the riders over a six-hour period after consuming each diet is shown in the accompanying graph. Which statement best summarizes the data in the graph?

Accepted Answer

The answer of  Each of three groups of cyclists...

Question 11

Which of the following statements is true regarding the digestive system in mammals?

Accepted Answer

The epiglottis acts as a flap that covers the trachea (windpipe) when swallowing, preventing food and liquid from entering the lungs. This ensures that swallowed substances go down the esophagus to the stomach instead.

Question 12

Jasmine, a 36-year-old female, visits her personal care physician complaining of muscle cramps and reduced appetite. Which of the following options would a doctor likely advise her to do to reduce her symptoms?

Accepted Answer

The answer of Jasmine, a 36-year-old female, visits her personal...

Question 13

In a hydra, digestion is completed ________.

Accepted Answer

The answer of In a hydra, digestion is completed ________.
...

Question 14

Termites are insects that eat a variety of dead plants, but they are most well-known for burrowing into wooden structures (including houses!) and eating the cellulose within the wood. What type of feeding mechanism do termites use?

Accepted Answer

Termites use substrate feeding as their feeding mechanism, where they digest the cellulose in wood or other plant materials directly from the environment they are consuming.

Question 15

Megaloblastic anemia results from a vitamin deficiency and causes abnormalities in red blood cell production and neurological issues. Megaloblastic anemia may be caused by a deficiency in which of the following vitamins?

Accepted Answer

Megaloblastic anemia is primarily caused by a deficiency in vitamin B12 or folate (vitamin B9), leading to abnormal red blood cell production and potential neurological issues. Vitamin B12 deficiency is a common cause.

Question 16

Gastroliths are stones that are used by the digestive systems of some animals to perform mechanical digestion. Fossilized gastroliths have been found with dinosaur skeletons. What does this evidence suggest about the digestive systems of dinosaurs?

Accepted Answer

Gastroliths are most commonly associated with the presence of a gizzard, an organ found in some animals that uses stones to grind up food, aiding in digestion. The discovery of gastroliths with dinosaur skeletons suggests that these dinosaurs likely had a similar digestive organ, indicating they had gizzards.

Question 17

Fat digestion yields fatty acids and glycerol, whereas protein digestion yields amino acids. Which of the following statements is true regarding these processes?

Accepted Answer

Both fat digestion and protein digestion involve hydrolysis reactions, which means they use water molecules to break the bonds within fats and proteins, respectively. This process is essential for breaking down these macromolecules into their smaller, absorbable components: fatty acids and glycerol from fats, and amino acids from proteins.

Question 18

Ticks are parasites that obtain nutrients by ingesting blood from a host animal. Ticks would be classified as ________.

Accepted Answer

Ticks are classified as fluid feeders because they consume the blood of their host animals, which is a fluid.

Question 19

The following table shows the contents of a multivitamin supplement and its percentage of recommended daily values (% DV).

The most likely reason that some of the vitamins and minerals in this supplement are found at less than 100% is that ________.

Accepted Answer

The answer of The following table shows the contents of...

Question 20

Which of the following statements correctly describes peristalsis?

Accepted Answer

Peristalsis is the series of wave-like muscle contractions that moves food to different processing stations in the digestive tract. It is most notably responsible for moving food down the esophagus and through the intestines, not related to fat emulsification, control of urination, or direct nutrient transport to the liver.

Quiz 42: Animal Digestive Systems