GI Tract

Question 1

Functions of digestive system

Answer 1

Break down food physically and chemically
Absorb water ‘excrete cholesterol

Question 2

Function of mouth

Answer 2

Breakdown of food
Food mixed with saliva and broken down into small pieces before being pushed by the tongue

Question 3

Pharynx

Answer 3

Food goes through pharynx from oral cavity to oesophagus through pharynx

Question 4

Oesphagus

Answer 4

Tube that moves food from the pharynx to the stomach via peristalsis

Question 5

Sph incter

Answer 5

Prevents back flow

Question 6

Tongue

Answer 6

Swallowing

Question 7

Salivary gland

Answer 7

Amylase

Question 8

Stomach

Answer 8

Food storage reservoir for food
Chemical digestion
Waves of peristalsis churn food

Question 9

Duodenum

Answer 9

Start of small intestine
Water enters through gut wall
Bile emulsify fats

Question 10

Liver

Answer 10

Produces bile
Emulsify fat

Question 11

Gall bladder

Answer 11

Store and concentrates bile

Question 12

Pancreas

Answer 12

Stores insulin and glucagon

Question 13

Jejunum

Answer 13

Next section after duodenum
Produces moulin to increase gastric motility
Mainly nutrient absorption

Question 14

Ileum

Answer 14

Secrete intestinal juice
Final digestion
Nutrient re absorption

Question 15

Large intestine

Answer 15

Final water and electrolyte absorption

Question 16

Caecum

Answer 16

Acts as a reservoir

Question 17

Rectum

Answer 17

Defeacation

Question 18

Carbohydrates structure

Answer 18

Alpha glucose
Helical and compact for energy storage
Water insoluble
Hydrolyse quickly
Starch - amylose - long straight chains amylopectin branched chains

Question 19

Carbs function

Answer 19

Every storage

Question 20

Protein structure

Answer 20

1 no and equence of amino acids
2 hydrogen bonds form - a helix or b pleated sheet
3 ionic, disulphide and hydrogen bonds form 3d shape
4 more than one polypeptide chains form

Question 21

Protein function

Answer 21

Acts as enzyme
Helps body repair cells

Question 22

Fat structure

Answer 22

Trigylercides 1 glycerols and 3 fatty acid
Phospholipid glycerol hydrophilic head 2 fatty acids hydrophobic tails
Saturated no double bonds
Unsaturated double bon

Question 23

Fat function

Answer 23

Energy source

Question 24

Digestion of carbs

Answer 24

In mouth an small intestines
Amylas - start into maltose
Matisse - maltose into glucose

Question 25

Protein digestion

Answer 25

Endopeptidase - hydrolyse Peptide bonds in middle
Exopeptidase - hydrolyse end bonds
dipeptidase hydroolyse peptide bonds in dipeptides

Question 26

Absorption of carbs

Answer 26

Co transport
Na ions transported out of cell so has low conc in epitheal cell
Na diffuse in and glucose is contransported in
Glucose moves out by facilitated diffusion into bloodstream

Question 27

Amino acids absorption

Answer 27

Specific ano acid cotransport proteins
For every na ion in a amino aid enters
By facilitated diffusion
Diffuses to capillaries

Question 28

Lipid absorption

Answer 28

Lipids emulsify by bile into smaller droplets
Lipase breaks down trigylercides into monooglycerdes
Then packed into micelles and absorbed by mmicrovilli
Converted into triglycerides in the er as monoglyceride and glycerol recombine
Then packaged into chylomicrons and then enter bloodstream

Question 29

Glycogenesis

Answer 29

Glucose molecules combines to make glycogen

Question 30

Glycogenolysis

Answer 30

Break down of glycogen to glucose

Question 31

Glycogeneogenesis

Answer 31

Generation of glucose from glycerol

Question 32

Glycolysis

Answer 32

Glucose to pyruvate
Glucose broken down to produce energy pyruvate and atp

Question 33

Insulin

Answer 33

Enables glucose to enter cells where they use t to produce energy
Reduces high blood sugar levels
Produced beta cells
Released into bloodstream when bloodstream when blood glucose are high and helps glucose in blood move across cell membrane into the cell

Question 34

Glucagon

Answer 34

Breaks down glycogen into glucose
Increases low blood sugar levels
Produced by alpha cells
Released into bloodstream when blood glucose levels are low and breaks down glycogen at stored in liver into glucose

Question 35

Healthy diet

Answer 35

Carbs
Dairy
Protein
Fats

Question 36

Gastric juice

Answer 36

Prevent bacterial growth
Convert Pepsinogen to pepsin

Question 37

Protein catabolism

Answer 37

When there is an excess of amino acids the amino group is removed - deamination
Creates by products co2 and ammonia
Ammmonia is converted into urea by the liver
Urea is excreted by the kidneys into urine