Human Physiology (Digestive System)

Front 1

What is needed for intrinsic factor in the stomach to form? What does intrinsic factor allow?

Back 1

B12

Calcium absorption

Front 2

What varies in the structure of the gastrointestinal tract according to function?

Back 2

Difference in:

- epithelial lining

- musculature

Front 3

What is segmentation? Where does it mainly occur?

Back 3

- Mixes food with enzymes

- Small intestine

Front 4

What is a trigger for peristalsis?

Back 4

Distension of gut by food

Front 5

What are the 3 functions of the stomach?

Back 5

- Storage

- Mixing

- Emptying

Front 6

What is distension of stomach detected by and what 2 responses does it cause?

Back 6

- Mechanoreceptors

- Gastrin release and stomach motility

Front 7

What 2 sphincters control exit of food from stomach?

Back 7

Antrum and pyloric

Front 8

What 2 factors stimulates release of CCK and where (2)?

Back 8

- Acids and fats in duodenum

- Fats in jejunum

Front 9

What stimulates release of secretin?

Back 9

Acidic chyme and fats

Front 10

What occurs in caecum?

Back 10

Drying of waste - water and ion absorption

Front 11

What is Haustration/ Haustral shuffling and where does it occur?

Back 11

Mixing movements in large intestine

Front 12

What does entero- mean?

Back 12

Relating to digestive system

Front 13

What 6 compounds are secreted by the stomach? What are their functions?

Back 13

- HCl (inhibits salivary alpha amylase)

- Pepsinogen (precursor -> acid activated)

- Gastrin (hormone - stimulates HCl and pepsinogen)

- Intrinsic factor (Ca absorption)

- Mucus (protection)

- hydrogen carbonate ions (neutralisation)

Front 14

What 3 things stimulates gastrin release?

Back 14

- Stomach distension

- Low pH

- Insulin

Front 15

What 5 compounds are secreted by the duodenal brush border?

Back 15

- Peptidases

- Oligosaccharides

- Secretin (stimulates exocrine pancreas)

- CCK (stimulates endocrine pancreas and bile production)

- Bicarbonate ions

Front 16

Give 2 examples of enterogastrones.

Back 16

CCK and secretin

Front 17

Give 3 functions of bile.

Back 17

- Emulsifies lipids so can be digested

- Removes waste bilirubin (colour) from haem

- Removes cholesterol

Front 18

What 5 compounds does the exocrine component of the pancreas produce? What is the best stimulus?

Back 18

- inactive proteases (e.g. trypsinogen)

- lipases

- pancreatic alpha amylase

- ribonucleases and deoxyribonucleases

- hydrogen carbonate ions

Secretin

Front 19

Give 7 functions of liver.

Back 19

- Ammonia -> urea

- Amino acid synthesis

- Plasma protein synthesis

- Glycogen storage

- Lipid metabolism

- Waste management (e.g. detoxification and haemoglobin break down)

- Bile production

Front 20

What are the 5 components of the portal triad?

Back 20

- Portal vein

- Hepatic artery

- Bile duct

- Vagus nerve

- Lymphatic branch

Front 21

What 2 stimuli are there for bile production?

Back 21

CCK and gastrin

Front 22

Where are carbohydrates absorbed (2) and what are they absorbed as (3)?

Back 22

duodenum and upper jejunum

- fructose, glucose, galactose

Front 23

By what process is glucose absorbed and in association with what process?

Back 23

- co-transport (secondary active transport)

- Sodium/potassium pump

Front 24

What did the experiment involving ouabain tell us about glucose absorption? What does it do?

Back 24

active transport involved

- inhibits sodium potassium pump ATPase

Front 25

Where are proteins absorbed (2)?

Back 25

Duodenum and ileum

Front 26

Where are lipids absorbed (1)?

Back 26

mid-jejunum

Front 27

What is lactose broken down into?

Back 27

sucrose and galactose

Front 28

What is sucrose broken down into?

Back 28

fructose and glucose

Front 29

What is starch/glycogen broken down into?

Back 29

individual glucose molecules

Front 30

What carriers are involved in the absorption of carbohydrate? Where are they situated and which molecules do they carry?

Back 30

SGLT1 (Na, G, GA) and GLUT5 (F) - apical membrane

GLUT2 (G, GA, F) and sodium-potassium pump - basolateral membrane

Front 31

What are the 4 symptoms of lactose intolerance?

Back 31

Undigested lactose enters colon causing:

- gas

- distension

- increased colonic motility

- diarrhoea

Front 32

What is the cause and treatment for glucose-galactose malabsorption?

Back 32

- SGLT1 gene faulty therefore no transporter

- Diet with fructose as carbohydrate source

Front 33

What can cause trypsinogen deficiency and what does it result in?

Back 33

Faulty trypsinogen gene

Reduced protein absorption

Front 34

What is cysteinuria and what can it cause

Back 34

Cysteine in urine

Kidney stones

Front 35

What is prolinuria?

Back 35

Proline and hydroxyproline in urine

Front 36

What are fatty acids absorbed into, what as and why?

Back 36

Lacteals

Chylomicrons (bundle of fatty acids so hydrophobic tails covered)

Front 37

What can cause malabsorption of lipids (3)?

Back 37

- Bile deficiency

- Intestinal mucosal atrophy

- Pancreatic insufficiency

Front 38

Where is water mostly absorbed?

Back 38

Jejunum

Front 39

What ion does water follow for absorption?

Back 39

Sodium

Front 40

Where is potassium mostly absorbed (2) and what does excessive loss result in?

Back 40

Jejunum and ileum

diarrhoea

Front 41

Why are Xenopus oocytes used in experiments?

Back 41

Because they have the ability to express foreign mRNA

Front 42

Compare type I, IIa and IIb muscle fibres.

Back 42

Type I = slow twitch

Type 2 = fast twitch (a = oxidative, b = glycolytic)