Module 2: Mammalian Digestive System

Question 1

Define digestion:

Answer 1

The break down of food into particle that are small enough to be absorbed into the bloodstream.

Question 2

What is Mechanical/Physical digestion?

Answer 2

The physical break down of food into smaller pieces to increase surface area.

Question 3

What is chemical digestion?

Answer 3

When digestive enzymes chemically break down larger molecules into simple ones that can be absorbed into the bloodstream.

Question 4

What are the three enzymes involved with digestion? What substances do they break down?

Answer 4

Amylase - Starch
Protease - Protein
Lipase - Fats

Question 5

What do starches and fats break down into?

Answer 5

Starch - maltose and glucose
Fats - fatty acids and glycerol

Question 6

Where are each of the digestive enzymes found?

Answer 6

Amylase - mouth and duodenum
Protease - Stomach and duodenum
Lipase - duodenum

Question 7

What is the pathway of food through the digestive system?

Answer 7

Digestion begins in the mouth.

After the food is swallowed it goes into the oesophagus.

Food goes into the stomach and then first part of the small intestine, called the duodenum.

Food then goes into the lower parts of the small intestine, called the jejunum and the ileum.

Waste is moved into the large intestine and is stored in the rectum.

Question 8

What is Peristalsis?

Answer 8

Muscle contractions that move food through the digestive tract.

Question 9

What is bolus?

Answer 9

Food that has been chewed and mixed in the mouth with saliva to form a ball shape.

Question 10

What’s the epiglottis?

Answer 10

A flap that covers the trachea during swallowing so that food does not enter the lungs.

Question 11

What is the trachea?

Answer 11

(Also known as the windpipe) The airway that leads from the larynx (voice box) to the bronchi.

Question 12

What does the stomach do?

Answer 12

Breaks food smaller pieces and combines it with gastric juices (called chyme)

Question 13

The stomach is very…

Answer 13

Acidic

Question 14

What are the three regions of the small intestine?

Answer 14

Duodenum - where most digestion occurs
Jejunum - Where the most absorption occurs
Ileum

Question 15

What are villi?

Answer 15

Microscopic finger like projections on the wall of the jejunum. They are one cell thick.

Question 16

How does nutrients enter the bloodstream from the digestive system?

Answer 16

Food enters the bloodstream through the villi which are connected to capillaries. This is done via diffusion or active transport.

Question 17

What does the large intestine do?

Answer 17

Absorbs water and minerals into the bloodstream. The remaining undigested food is stored in the rectum as faeces.

Question 18

Bile produced by the liver and stored in…

Answer 18

The gallbladder

Question 19

What does bile do?

Answer 19

Helps digest fat molecules to increase
surface area for breakdown by lipases.

Question 20

What does the liver do?

Answer 20

Produces bile for fat digestion
Filters drugs and toxin from the blood
Breaks down the nutrients and processes vitamins

Question 21

What does the liver do with toxins?

Answer 21

Converts them into urea which is passes out of the body in urine.

Question 22

What does the pancreas do?

Answer 22

The pancreas releases many different digestive enzymes and bicarbonate ions.

Question 23

What do bicarbonate ions do, where are they secreted from?

Answer 23

The pancreas secretes bicarbonates, which help in neutralizing stomach acid.