Digestion

Question 1

what is digestion?

Answer 1

the breakdown of food chemically or manually in order to utilise nutrients

Question 2

what is mechanical digestion?

Answer 2

teeth breaking up the food (chewing or mastication)

Question 3

what is salivary amylase and where does it take place?

Answer 3

initiates digestion of starch

mouth

Question 4

what is pancreatic amylase and where does it take place?

Answer 4

breaks down polysaccharides into shorter glucose chains and disaccharides

small intestine

Question 5

what is lingual lipase and where does it take place?

Answer 5

initiates digestion of triglycerides into smaller FA

mouth

Question 6

what is pepsin and where does it take place?

Answer 6

an enzyme that breaks down large proteins into amino acids

stomach

Question 7

what is trypsin and where does it take place?

Answer 7

breaks the shorter polypeptide chains into singular amino acids and shorter peptide chains

small intestine

Question 8

what is chemical digestion and what does it include?

Answer 8

saliva is released by the salivary gland which contains enzymes

includes amylase and lingual lipase

Question 9

What is the order of the digestive tract?

Answer 9

1. pharynx
2. oesopagus
3. stomach
4. small intestine
5. large intestine
6. rectum

Question 10

what is the oesophagus?

Answer 10

a muscular tube that has two sphincter muscles (lower and upper)

Question 11

what are the three sections of the small intestine and what happens in them?

Answer 11

duodenum - most digestion occurs
jejunum and ileum - absorption of nutrients and water occurs

Question 12

what happens in the large intestine?

Answer 12

• water and nutrients are absorbed
• bacteria ferments soluble fibre
• undigested solid materials pass through and exit through the rectum

Question 13

What is bile?

Answer 13

Bile is a fluid that is made and released by theliverand stored in thegallbladder. Bile helps withdigestion. It breaks downfatsinto fatty acids, which can be taken into thebodyby the digestive tract.

Question 14

What is the chemical digestion of carbs?

Answer 14

1. mouth - breakdown of starch by salivary amylase into short polysaccharides
2. stomach - carb digestion is reduced
3. small intestine - pancreatic amyalse breaks down polysaccharides into shorter glucose chains and disaccharides
4. small intestine - specific disaccharide enzymes finish carb digestion into monosachharides ready for absorption into the bloodstream
5. large intestine - soluble fibre is fermented by bacteria

Question 15

What is the chemical digestion of lipids?

Answer 15

1. mouth - slight breakdown of lipids into smaller fatty acid chains by lingual lipase
2. stomach - minimal chemical digestion of lipids
3. small intestine - pancreatic lipase efficiently breaks down small fat droplets into singular fatty acid chains, glycerol or monoglycerides to allow them to be absorbed into the bloodstream or lymphatic system

Question 16

What is the chemical digestion of proteins?

Answer 16

1. mouth - no chemical break down of protein
2. stomach - hydrochloric acid converts inactive pepsinogen into its active form pepsin
3. hydrochloric acid uncoils and dentures each protein strand to allow gastric pepsin to break the peptide bonds between amino acids, making shorter polypeptide chains
4. small intestine - pancreatic and intestinal proteases, including trypsin and chymotrypsin break the short polypeptide chains into singluar amino acids and shorter peptide chains
5. small intestine - intestinal peptidase completes the digestion of the shorter peptides into singular amino acids ready for absorption into the bloodstream