2.1 Part 1 - Basics of the digestive and endocrine systems

Question 1

What is the digestive system? (GI tract)

Answer 1

• digestive and absorptive organ system

- Releases enzymes and hormones to digest food

Question 2

Amylase is found in the BLANK and digests BLANK into BLANK

Answer 2

Amylase is found in the SALIVA of the mouth it breaks down STARCH into MALTOSE

Question 3

Proteases (pepsin) and hydrochloric acid are BLANK and digest BLANK into BLANK

Answer 3

Protease and hydrochloric acid are GASTRIC JUICES and digest PROTEINS into PEPTIDES

Question 4

Proteases (trypsin), Lipases and Amylase are Pancreatic juices that digest BLANKS into BLANKS

Answer 4

Proteases (trypsin), Lipases and Amylases

digest: into

Proteins: peptides and amino acids

Fats emulsified by bile: fatty acids and glycerol

Starch: maltose

Question 5

Intestinal enzymes:
Peptidases
Sucrase
Lactase
Maltase

digest what into what?

Answer 5

Peptidases: Peptides > Amino acids

Sucrase: Sucrose (sugar) > glucose and fructose

Lactase: Lactose (milk sugar) > glucose and fructose

Maltase: Maltose > glucose

Question 6

What two places specifically produce amylase?

Answer 6

• Pancreas

- Salivary glands in the mouth

Question 7

Salivary glands produce amylase and a small amount of what?

Answer 7

Lipase!

Question 8

What is the main function of the mouth and one smaller secondary function?

Answer 8

Digestive - breaking down of foods

Absorption (only a small amount) eg: soluble drugs

Question 9

What does chewing/mouth trigger?

Answer 9

Stimulates stomach and other organs to begin producing acid, mucus, enzymes and bile

Question 10

Define satiety:

Answer 10

The state of being full

Question 11

What does the satiety index refer to?

Answer 11

Foods that tend to produce greater effects of ‘feeling full’ when calories are equated

Question 12

What effects do the following hormones have on appetite?

CCK (Cholecystokinin)
Ghrelin
Peptide YY
GLP-1 (glucagon like peptide)

Answer 12

CCK = reduce A
Ghrelin = increase A
Peptide YY = reduce A
GLP-1 = reduce A

Question 13

Stomachs main function?

Answer 13

To digest food

Question 14

Stretch receptors in the stomach send signals via the BLANK BLANK to tell the brain what?

Answer 14

Via the vagus nerve to tell the brain how full the stomach is

Question 15

When a more calorie dense meal is consumed what effect does this have on gastric emptying?

Answer 15

It generally will increase the time it takes for gastric emptying to occur

Question 16

Role of the gallbladder?

Answer 16

To STORE bile (liver secretes it - important note)

It is then released to digest fat in the duodenum of the small intestines (I guess like a reservoir?)

Question 17

Main function of the small intestine?

2 small notes on structure of the small intestines

Answer 17

Absorb nutrients (most happens here)

via

1) Microvilli
2) A very large surface area to allow more absorption

Question 18

What are the 3 key sections of the small intestine?

Answer 18

1) duodenum
2) Jejunum
3) Ileum

Question 19

Enterocytes are what?

Answer 19

The absorptive cells in the intestines

Question 20

3 key enzymes in the small intestine? (and what group of enzymes are also released into the small intestine via the pancreas?)

Answer 20

Lipase, amylase, protease

Proteolytic enzymes from the pancreas

Question 21

2 key enzymes released from the pancreas and their functions?

Answer 21

Insulin - reduce blood sugar

Glucagon - increase blood sugar

Question 22

When are pancreatic juices (digestive enzymes) released?

Answer 22

When it detects macronutrients entering the duodenum

Question 23

What is the sequence of things that happens when the body detects low blood glucose?

Answer 23

1) pancreas releases glucagon from the alpha cells
2) This stimulates liver to release glucose into the blood
3) blood glucose normalised

(note there are other mechanisms that can contribute to this - this is the basic)

Question 24

What is the sequence of things that happens when the body detects high blood glucose?

Answer 24

1) Insulin released by beta cells of pancreas
2) Cells take in more glucose from blood
3) blood glucose normalised

** note: glucose oxidation increases when this happens too so our body actively tries to burn more energy!

Question 25

What is the large intestine often referred to and why?

Answer 25

‘The forgotten organ’ - because of its immense impact on the body. However we do not really understand HOW as of yet, we only know that it does.

This is largely in part due to ‘gut flora’ (bacteria balance)

Question 26

The large intestine ferments what?

Answer 26

Indigestible carbs

Question 27

What is dysbiosis?

Answer 27

Bacteria imbalance of the small intestine

Question 28

What is IBS-C and IBS-D?

and what are some potential treatments for each?

Answer 28

irritable bowel syndrome:

C = constipation

• hydrate
• increase soluble fibre
• possible hypothyroid

D = Diarrhoea

• reduce insoluble fibre
• reduce caffeine
• reduce polyols
• stress management

Question 29

4 primary functions of the liver?

Answer 29

1) Bile production and secretion
2) storage of CHO and fat sol vits
3) Synthesises glucose
4) processes hormones, drugs, toxins

Question 30

3 primary functions of the kidneys?

Answer 30

1) Regulates electrolyte balance
2) Maintains pH balance
3) Excretes urine to the bladder