Section: Digestion
Name:_______________________________________________
Complete each statement by writing the correct term or phrase in the space provided.
1. The process of breaking down food into molecules the body can use is called _digestion_.
2. _chemical_ digestion involves breaking the chemical bonds in food.
3. Examples of __mechanical_ digestion are chewing food in the mouth and churning food in the stomach.
Study the following major functions of the digestive system. Determine the order in which the
functions are carried out. Write the number of each step in the space provided.
4. __3__The small molecules are taken up by the body.
5. __2__The digestive system breaks down the food into molecules small enough for the body to absorb.
6. __1__Food is taken in by the digestive system.
7. __4__The digestive system gets rid of undigested food and waste.
Complete each statement by writing the correct term or phrase in the space provided.
8. Digestion begins in the _mouth________________.
9. Saliva contains ___amylase____________, enzymes that start the chemical breakdown of starches.
10. The ___esophagus___________ is a long tube that connects the mouth to the stomach.
11. Successive rhythmic waves of smooth muscle contractions in the esophagus are called _peristalsis.
Compare & contrast these terms.
12. gastric juice, pepsin
Gastric juice, a combination of HCl and pepsin, is secreted by the cells that line the inside of the stomach. Pepsin,
a digestive enzyme that breaks down proteins into smaller chains of amino acids, is part of gastric juice.
13. mucous coating, ulcer
A mucous coating covers the walls of the stomach and protects it from stomach acids. An
ulcer is a painful sore that results when stomach acids eat through part of the stomach
lining.
Use the picture on the right.
14. __a_ The structure labeled B is a
a. villus.
c.
b. nephron.
d.
15. _c__ 9. Structure B is found in the
a. kidneys.
c.
b. esophagus.
d.
16. _a__ Structure B allows for an increase in
a. absorption area.
c.
b. mechanical digestion.
d.
Read each question, and write your answer in the space provided.
17. What role does the pancreas play in digestion?
ureter.
urethra.
small intestine.
Tongue
acid production.
bile production.
The pancreas secretes digestive enzymes into the small intestine.
18. What is bile, and where does it come from?
Bile is a fluid made in the liver, which breaks down fat globules and aids in the absorption of fatty acids and fatsoluble vitamins.
19. What are villi, and what important structures do they contain?
Villi are fingerlike projections that line the small intestine. They contain capillaries and lymphatic vessels.
20. What happens to digested sugars and amino acids inside the small intestine?
They are absorbed by the capillaries in the villi and are transported to the liver.
21. What are two functions of the large intestine?
The large intestine absorbs water and mineral ions and packs solid wastes together.
22. What happens if water absorption in the large intestine gets off balance?
Too much water in the large intestine causes diarrhea (watery feces). Too little water results in constipation (hard
feces).
Interpreting Graphics
The figure at right shows the digestive system. In the spaces
provided, label the following parts of the digestive system: liver,
throat, stomach, gallbladder, mouth, esophagus, small intestine,
and large intestine.
23. ___mouth_______________
24. ___throat______________
25. ___esophagus___________
26. ___stomach____________
27. ___liver_______________
28. ___gallbladder_________
29. ___large intestine_____
30. ___small intestine_____
31. The table below lists information about digestive secretions.
Complete the table by writing the correct term or phrase in
the space provided.
Digestive Secretion
Digestive tract area
released into
Mouth
Nutrient secretion
acts on
Amylase
Organ/Structure
released by
Salivary glands
Pepsin
Cells in stomach lining
stomach
proteins
Bile
Liver
small intestine
Fat globules
Lipase
pancreas
small intestine
Fats
starch
Quiz. Section: Digestion In the space provided, write the letter of the term or phrase that best
completes each statement or best answers each question.
1. __b__ All of the following occur in the stomach except
a. temporary food storage.
c. mechanical digestion.
b. release of amylases.
d. chemical digestion.
2. __c__ The small intestine receives secretions from which of the following?
a. saliva
c. pancreas
b. stomach
d. large intestine
3. __c__ Which of the following is involved in mechanical digestion?
a. throat
c. teeth
b. large intestine
d. pancreas
4. __d__ The liver performs all of the following functions except
a. producing bile.
c. stabilizing blood sugar levels.
b. detoxifying poisons.
d. digesting proteins.
In the space provided, write the letter of the description that best matches the term or phrase.
5. _a___ mouth
a. beginning of the digestive tract
6. _d___ pancreas
b. area of the digestive tract that contains villi
7. _f___ esophagus
c. area of the digestive tract that follows the esophagus
8. _c___ stomach
d. secretes digestive enzymes into the small intestine
9. _b___ small intestine
e. area of the digestive tract where water and mineral ions are absorbed
10. _e___ large intestine
f. long tube that connects the mouth to the stomach