Week 2 - Digestive System

Question 1

Digestive Tract

Answer 1

Tube from the mouth to the anus and Accessory organs

Question 2

Gastrointestinal tract

Answer 2

Only the stomach and the intestines

Question 3

Digestive system components in order

Answer 3

Oral cavity (mouth)
Accessory organs - tonsils and salivary glands
Pharynx (throat)
Oesophagus
Stomach
Small intestine - Duodenum, Jejunum and Ileum
Accessory organs - Liver, Gallbladder and Pancreas
Large Intestine - Cecum, Colon, Rectum and Anal canal

Question 4

Digestive System Functions

Answer 4

Ingestion, mastication, propulsion, mixing, secretion, digestion, absorption, elimination

Question 5

Mastication

Answer 5

food is mechanically broken down. Increases the total

surface area to allow digestive enzymes access

Question 6

Propulsion

Answer 6

the movement of food through the digestive tract

Question 7

Three types of propulsion

Answer 7

Swallowing - Moves bolus from oral cavity into oesophagus
Peristalsis - wave of smooth muscle relaxes in front of bolus and wave of smooth muscle contracts behind bolus which pushes it through the oesophagus and small intestine
Mass movements - contractions that move material in the large intestine

Question 8

Mixing

Answer 8

Segmental contractions to mix food with digestive secretions in the small intestine

Question 9

What type of secretion occurs in the digestive tract

Answer 9

Mucus secreted by the digestive tract and enzymes secreted from pancreas, small intestine, stomach and oral cavity help break down food

Water also helps this

Question 10

Digestion (2 types)

Answer 10

Mechanical - mastication and mixing

Chemical - digestive enzymes

Question 11

Describe an enzyme

Answer 11

A substance that increases the speed of a reaction without being changed or used up in the process - is usually always a protein

Question 12

Two mechanisms that describe the action of enzymes

Answer 12

Lock and key hypothesis - enzyme + substrate enter an active site and combine (COMBINE)
Induced fit model - substrate enters active site of enzyme and it breaks the substrate down (BREAKS DOWN)

Question 13

Name the 3 Carbohydrate (saccharides)

Answer 13

Polysaccharide, Disaccharide, Monosaccharide

Question 14

What are proteins composed of and how are they held together

Answer 14

Amino Acid and held together by Peptide bonds

Question 15

Name the 3 Lipids

Answer 15

Fatty Acids, Triglyceride, Glycerol

Question 16

Types of digestive enzymes

Answer 16

Amylase breaks down sugars (carbs), Lipase breaks down fat, Protease breaks down protein

Question 17

What affects enzyme function

Answer 17

Temperature and pH

Question 18

Amylase

Answer 18

Break down carbs

Question 19

Lipase

Answer 19

Break down lipids (fats)

Question 20

Protease

Answer 20

Break down proteins

Question 21

What occurs in the large intestine turning bolus into feces

Answer 21

It absorbs water and salts

Question 22

4 layers of digestive tract

Answer 22

Mucosa
Submucosa
Muscularis
Serosa

Question 23

Mucosa contain 2 receptors

Answer 23

Mechanoreceptors

Chemoreceptors

Question 24

Submucosa contains

Answer 24

Nerves, lymphatic and blood vessels and small glands

Question 25

What type of muscle is the Muscularis of the digestive tract

Answer 25

Smooth muscle

Question 26

Serosa

Answer 26

Smooth layer that covers the digestive tract organs

Question 27

Enteric Nervous System (ENS)

Answer 27

A division of the ANS located within the digestive tract walls and can work independently to ANS

Question 28

What does the PNS do to digestion

Answer 28

Increases motility, salivary and gastric acid secretions

Question 29

What does the SNS do to digestion

Answer 29

Decreases motility

Question 30

3 endocrine secretions

Answer 30

Gastrin (tells the stomach to release gastric acid), Secretin (regulated water homeostasis throughout the body and influences the environment in the duodenum by regulating secretions in the stomach, pancreas and liver, Cholecystokinin (tells gallbladder to secrete bile when the upper small intestine becomes acidic)