Digestion and absorption：练习题

In which part of the digestive system does the chemical digestion of proteins first begin?

What is the primary role of hydrochloric acid (HCl) in the stomach during the digestion process?

Which specific enzyme in the ileum is responsible for converting sucrose into glucose and fructose?

What is the name of the rhythmic, wave-like muscular contractions that move food along the digestive tract?

Which of the following is an inactive enzyme precursor found in pancreatic juice that must be activated before it can digest proteins?

Identify the specific enzyme found in the mouth and name the substrate it acts upon during the initial stage of digestion.

Identify the final end products of protein digestion and name the enzyme in the ileum that completes this final stage.

Differentiate between the types of nutrients absorbed into the blood capillaries of the villi and those absorbed into the lacteals.

Digestion is the process of breaking down food into a form that the body can use.

(a) List four main stages or locations in the digestive system where digestion occurs.
(b) Name the specific enzyme found in saliva and describe its function in the chemical digestion of food.

The stomach provides a unique environment for the initial digestion of proteins.

(a) Describe how mechanical digestion is achieved in the stomach.
(b) Explain the role of hydrochloric acid in the gastric juice.
(c) State the functions of the enzymes pepsin and rennin within the stomach.