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Biology 2e

Critical Thinking Questions

Biology 2eCritical Thinking Questions

Critical Thinking Questions

20.

How does the polygastric digestive system aid in digesting roughage?

21.

How do birds digest their food in the absence of teeth?

22.

What is the role of the accessory organs in digestion?

23.

Explain how the villi and microvilli aid in absorption.

24.

Name two components of the digestive system that perform mechanical digestion. Describe how mechanical digestion contributes to acquiring nutrients from food.

25.

What are essential nutrients?

26.

What is the role of minerals in maintaining good health?

27.

Discuss why obesity is a growing epidemic.

28.

There are several nations where malnourishment is a common occurrence. What may be some of the health challenges posed by malnutrition?

29.

Generally describe how a piece of bread can power your legs as you walk up a flight of stairs.

30.

In the 1990s fat-free foods became popular among people trying to lose weight. However, many dieticians now conclude that the fat-free trend made people less healthy and heavier. Describe how this could occur.

31.

Explain why some dietary lipid is a necessary part of a balanced diet.

32.

The gut microbiome (the bacterial colonies in the intestines) have become a popular area of study in biomedical research. How could varying gut microbiomes impact a person’s nutrition?

33.

Many mammals become ill if they drink milk as adults even though they could consume it as babies. What causes this digestive issue?

34.

Describe how hormones regulate digestion.

35.

Describe one or more scenarios where loss of hormonal regulation of digestion can lead to diseases.

36.

A scientist is studying a model that has a mutation in the receptor for somatostatin that prevents hormone binding. How would this mutation affect the structure and function of the digestive system?

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