Digestive system

Question 1

What are the four stages of digestion?

Answer 1

Ingestion, digestion, absorption, elimination

Question 2

What is digestion?

Answer 2

Process of breaking food down into molecules small enough to absorb

Question 3

What type of digestion occurs in the mouth when food is mixed or crushed with your teeth?

Answer 3

Mechanical digestion

Question 4

What is the chemical digestion that occurs in the mouth?

Answer 4

Digestive enzymes break down complex polymers into monomers

Question 5

What is an enzyme?

Answer 5

Molecule that allows a substances to be converted into smaller molecules

Question 6

1. What is amylase?

2. What does it do?

Answer 6

1. An enzyme produced by the salivary glands and found in saliva
2. Breaks down starch into maltose

Question 7

What does the tongue do to the food in the mouth?

Answer 7

Forms it into a bolus

Question 8

1. When is the swallowing reflex stimulated?
2. What is the pharynx?
3. What is an epiglottis?

Answer 8

1. When food enters the pharynx
2. Place in throat that opens up into trachea and esophagus
3. A flap that flops down over the windpipe and allows food to enter esophagus

Question 9

1. How long is the esophagus and what does it connect to?

2. What is the sphincter valve?

Answer 9

1. 25cm, connects to stomach

2. Food enters it but is prevented from going back up

Question 10

What is peristalsis?

Answer 10

When food is pushed down the esophagus with help of involuntary muscle contractions

Question 11

What are the stomach’s 3 functions?

Answer 11

1. To store up to 2L of food and fluid
2. To break down the food into liquid mixture
3. To slowly empty liquid mixture into small intestine

Question 12

What is churning?

Answer 12

When the smooth muscle in the stomach mixes the food

Question 13

What is gastric juice made up of?

Answer 13

Hydrochloric acid, mucous, enzyme pepsin

Question 14

1. What does the hydrochloric acid in the gastric juice do?
2. What is the role of pepsin?
3. What does mucous do?

Answer 14

1. Breaks down meat and plant material, kills bacteria in food
2. Breaks down proteins into smaller amino acid chains
3. Protects the lining of the stomach from the acid

Question 15

1. What does the bolus become?

2. This liquid is released from the stomach via what?

Answer 15

1. Acid chyme

2. Pyloric sphincter

Question 16

What can decrease the amount of mucous in the stomach?

Answer 16

Helicobacter pylori or chronic use of medication

Question 17

If the inner linings of the stomach are exposed to acid, what does this cause?

Answer 17

1. Irritation (gastritis)

2. Ulcers (sore/hole in stomach)

Question 18

1. Approx. how long is the small intestine?
2. What is its main function?
3. What are the names of the 3 parts of this organ?

Answer 18

1. 6-7m long
2. Transport nutrients into your bloodstream
3. Duodenum, jejenum, ileum

Question 19

1. What are villi?

2. What does each villi contain?

Answer 19

1. Folds on the small intestine that look like fingers and are made up of epithelial cells
2. Microvilli

Question 20

Why do villi and microvilli increase the surface area of the small intestine?

Answer 20

1. Allows more nutrients to be absorbed into the bloodstream

2. Nutrients are absorbed into the blood faster

Question 21

In the duodenum, the acid chyme mixes with digestive juices from which 3 other organs?

Answer 21

Pancreas, liver, gallbladder

Question 22

1. What enzymes does the pancreas produce and why?

2. What else does it produce and why?

Answer 22

1. Lipase, to break down fats

2. Basic solution to neutralize the acid from chyme

Question 23

1. What does the liver produce?
2. What is it?
3. Where is it stored?

Answer 23

1. Bile
2. A liquid that allows fats to be absorbed into the bloodstream
3. Gallbladder

Question 24

What are the liver’s functions?

Answer 24

1. To filter out harmful substances and turn some into more bile
2. Determines the amount of nutrients that will be distributed to the body

Question 25

1. Small intestine empties into the ______ of the large intestine.
2. Waste products will be stored in the ___.

Answer 25

1. Cecum

2. Rectum