Digest gen

Question 1

The digestive system is divided into 2 main parts

Answer 1

Alimentary Canal or Gastro-Intestinal Tract
Accessory Organs of Digestion

Question 2

Alimentary Canal or Gastro-Intestinal Tract

Answer 2

Includes the mouth, pharynx, oesophagus, stomach, small intestine and large intestine.

Question 3

Accessory Organs of Digestion

Answer 3

These release substances into the digestive tract through ducts. Structures include the salivary glands, liver, gall bladder and pancreas.

Question 4

Alimentary Canal or Gastro-Intestinal Tract

Answer 4

This is 7 – 10 metres in length, it begins at the mouth and ends at the anus.

Question 5

Saliva in the mouth

Answer 5

Saliva from the salivary glands, parotid, submandibular and sublingual glands lubricate the food with mucus until it becomes a mass called a bolus

Question 6

mastication

Answer 6

The teeth help to breakdown the food by a process called mastication.

Question 7

Bolus

Question 8

breakdown of carbohydrates begins?

Answer 8

The breakdown of carbohydrates begins in the mouth

Question 9

Pharynx (throat)

Answer 9

This muscular tube passes the bolus down to the oesophagus. The epiglottis, a flap of cartilage, prevents the food from entering the lungs

Question 10

structure Oesophagus (food pipe)

Answer 10

10 inch long muscular tube
Consists of a muscular tube leading to the stomach.

Question 11

Function Oesophagus (food pipe)

Answer 11

The wall of the oesophagus not only releases mucus to help break down the food but it also creates a wave of muscular contractions which propels the bolus down to the stomach. This process is called peristalsis

Question 12

Stomach located

Answer 12

This is a muscular J shaped sac situated on the left hand side of the body beneath the diaphragm.

Question 13

Lining of the stomach?

Answer 13

It is lined with folds of rugae that allow it to stretch and contract.

Question 14

There are 2 sphincter muscles one at each end to control the movement of food.

Answer 14

Enters from the oesophagus vid Cardiac and
Leaves pyloric to duodenum

Question 15

Bolus turns to

Answer 15

chyme

Question 16

What do gastric juices in the stomach comprise of

Answer 16

gastic juices containing enzymes and hydrochloric acid which kills bacteria.

Question 17

The pyloric sphincter muscle

Answer 17

The pyloric sphincter muscle controls the entry of chyme into the small intestine (duodenum)

Question 18

Small Intestine structure

Answer 18

This is approximately 6 – 7 metres long and divided into 3 parts:
- Duodenum
- Jejunum
- Ileum

Question 19

the wall of the duodenum secrets?

Answer 19

The wall of the duodenum secretes mucus to protect it from the acidic chime from the stomach.

Question 20

breakdown of proteins begins?

Answer 20

The breakdown of proteins begins in the stomach

Question 21

Bolus enters the stomach and

Answer 21

The bolus enters the stomach where it is broken down further into a liquid called chyme by gastic juices containing enzymes and hydrochloric acid which kills bacteria.

Question 22

function of small intestine

Answer 22

Cells of the small intestine secrete enzymes to digest proteins, carbohydrates and fats

Digestive juices from the liver and the pancreas enter via an opening in the duodenum to help the process.

Nutrients are passed into the blood stream and waste materials and indigestible products are moved into the large intestine.

Question 23

villi

Answer 23

The surface of the small intestine consists of tiny projections called villi which increase the surface space for absorption of nutrients.

Question 24

Large Intestine (colon) Consists of 3 parts

Answer 24

Ascending colon
Transverse colon
Descending colon

Question 25

function of the large intestine

Answer 25

absorbing water and electrolytes
producing and absorbing vitamins
forming and propelling feces toward the rectum for elimination.

Question 26

Sigmoid Colon

Answer 26

The sigmoid colon is located on the lower part of the descending colon as it forms a ‘S’ shape. The sigmoid colon empties into the rectum

Question 27

Appendix

Answer 27

This is a small blind tube containing lymphoid tissue located in the large intestine attached to a small pouch called the cecum. Inflammation of this tissue is known as appendicitis.

Question 28

Rectum

Answer 28

The waste material is stored here before being passed down the anal canal and through an opening out of the body called the anus.

Question 29

Peritoneum

Answer 29

This is the lining of the abdominal / pelvic cavity. It is a thin shiny serous membrane that also folds back to cover the organs contained within the cavity to support, bind and secrete a lubricating fluid that allows the organs to slide against each other.

Question 30

Enzyme

Answer 30

Organic catalyst which speeds up a chemical reaction but is not changed in the reaction.

Question 31

Sphincter

Answer 31

Permits the passage of substances in one direction only

Question 32

Peristalsis

Answer 32

Wave like motion in the wall of an organ that propels the substance along

Question 33

Salivary Glands function

Answer 33

These produce saliva that moistens the food and helps the process of mastication, reduce bacterial growth, clean the teeth and mouth.

Question 34

Saliva contains

Answer 34

Saliva contains mucus and salivary amylase, an enzyme which helps convert starch to sugar.

Question 35

where is the pancreas?

Answer 35

The pancreas is located behind the stomach, between the spleen and the duodenum.

Question 36

function of the pancreas?

Answer 36

The exocrine pancreas produces enzymes that help to digest food, particularly protein.

The endocrine pancreas makes the hormone insulin, which helps to control blood sugar levels.