Digestive System

Question 1

What does the tongue do?

Answer 1

Helps push food in the mouth (bolus) backwards into the pharynx.

Question 2

What do teeth do?

Name the four types of teeth and their purpose.

Answer 2

Food is ground by teeth; this is mechanical digestion.
There are 4 types of teeth?
1. Flat Incisors, biting
2. Pointed Canines, tearing
3. Premolars, grinding
4. Molars, crushing and chewing

Question 3

What do salivary glands do?

Answer 3

Release saliva,
Saliva contains enzymes called amylase which breaks down carbs,
Also moistens/lubricates food for easier swallowing.

Question 4

What is bolus?

Answer 4

Chewed and saliva filled food the enters your esophagus.

Question 5

What is your esophagus and what does it do?

Answer 5

It is a long tube that connects the oral cavity to the stomach.
Made of smooth muscle, that has the ability to stretch to allow bolus to be pushed through.
Wavelike contraction is called peristalsis; reverse peristalsis is vomiting.

Question 6

What is the epiglottis and what does it do?

Answer 6

The epiglottis is the flap that covers the larynx (at top of trachea/windpipe), sealing off the opening to the respiratory system.

Question 7

What is the pharynx?

Answer 7

Region at the back of the mouth shared by both the digestive and respiratory system.
Ulna and epiglottis block off pipes to the other systems.

Question 8

What are sphincters?

Answer 8

Rings of muscle surrounding and serving to guard or close an opening or tube, such as the openings of the stomach, the expand and contract.
e.g. The Pyloric Sphincter is contracted and opens slightly to let a small amount of chyme through.

Question 9

What does the stomach do?

What are it’s 3 main functions?

Answer 9

Food passes through the cardiac sphincter into the stomach, which is a muscular sac that can hold 2-4L of food and liquids.
Bolus reaches the stomach, is now referred to a chyme
3 major functions:
1. Store food and release some into small intestine through pyloric sphincter
2. Assist in mechinacal breakdown by peristalsis and churning contractions
3. Chemical digestion though hydrochloric acid, pepsin, and rennin

Question 10

What is the small intestine?

What does it do?

Answer 10

Is 6-7m long and 3.5-5cm wide 
Has 3 parts;
1. Duodenum
2. Jejunum
3. Ileum 

3 juices that help small intestine chemically digest food;

1. Bile; from the liver, breaks down lipids
2. Pancreatic Juices; from pancreas, breaks down carbs (amylase), protein (proteases), fat/lipids (lipases)
3. Intestional Juices; from intestine, breaks down carbs, protein, and lipids

Food is transfered by peristalsis.

Have villi that project from the lining and increase surface area for nutrient absorption

Question 11

What does the large intestine do?

Answer 11

1.5m long and connected to the Ileum, the Ileaceacal valve controls passage of large intestine
The large intestine absorbs water and produces vitamins (K&B)
It also egests unwanted materials in the form of feces or stool.

Question 12

What does the rectum do?

Answer 12

Last portion of the large intestine that is used for storage ready for disposal, when it becomes full, it triggers nerves that carry a message to the brain to go to the washroom.

Question 13

What does the anus do?

Answer 13

The anus is the exit for the digestive system for the feces of all the left over material not used by the body.

Question 14

What does the appendix do?

Answer 14

The appendix is approx. 7cm long and has no known function.

Removal in necessary is it becomes inflamed, that may cause a bacterial infection and or compacted fecal matter.

Question 15

What does the liver do?

Answer 15

-Produces bile that is stored in the gallbladder
This is released into the small intestine to help physically break down lipids smaller
- Stores carbs for energy
- Reguates blood glucose levels
- Stores iron and vitamins (A, B12, D, K)
-Detoxifies the blood (of alcohol and such)
-Converts ammonia into urea

Question 16

What does the gallbladder do?

Answer 16

Stores the bile in from the liver before releasing it into the small intestine.

Question 17

What does the pancreas do?

Answer 17

Consists of two major types of cells:

1. Produces cells for hormones involved in blood sugar regulation
2. Creates pancreatic juices
   - Bicarbonate ions released from pancreas to neutralize HCl
   - Amylase- Digests carbs
   - Proteases- Digests proteins
   - Lipases - Digests lipids

Neutralized acidic chyme

Question 18

What does the uvula do?

Answer 18

Is a flap of cartilage that prevents food from going up our noses.

Question 19

What is amylase? Is it physical or chemical digestion?

Where are they made, where are they used

Answer 19

An enzyme that digests carbs (Chemical Digestion)
Made in pancreas, small intestine, and salivary glands in mouth.
Used in small intestine and in mouth.

Question 20

What are proteases? Is it physical or chemical digestion?

Where are they made, where are they used?

Answer 20

There an enzyme that digests protein (Chemical Digestion)
Made in pancreas, and small intestine
Used in small intestine.

Question 21

What is bile? Is it physical or chemical digestion?

Where is it made, where is it used?

Answer 21

Its a physical digestion of lipids
Made in the liver, stored in the gallbladder.
It is used in the small intestine.

Question 22

What is lipase? Is it physical or chemical digestion?

Where is it made, where is it used?

Answer 22

Is an enzyme that digests lipids (Chemical)
Made in the pancreas, and small intestine.
Used in the small intestine.

Question 23

What is bicarbonate?

Where is made, where is it used?

Answer 23

Is an ion used to neutralize HCL from the stomach.
Made in the pancreas.
Works in the small intestine.

Question 24

What are pepsin and rennin?

Answer 24

They are enzymes found in the stomach to aid in protein digestion.

Question 25

What is gastric juice?

Answer 25

A hormone found in the stomach that stimulates the production and secretion of hydrochloric acid.