digestion

Question 1

what are the major parts of the digestive system

Answer 1

1) the oesophagus- transports food to stomach
2) ileum- long muscular tube
3) large intestine - absorbs water
4) rectum - faeces stored here
5) anus - faeces removed by egestion
6) salivary glands - secrete amylase (hydrolyses starch into maltose)
7) pancreas - produces hydrolysing secretion

Question 2

what are endopeptidases

Answer 2

• hydrolyse peptide bonds in polypeptide chain
• creates more terminal ends for exopeptidase to work on

Question 3

what do exopeptidases do?

Answer 3

• hydrolyses terminal peptide bonds
• to remove individual amino acids
• creates smaller polypeptide chain

Question 4

what the structural adaptations of the ileum

Answer 4

1) very thin walled - reducing diffusion distance
2)contain muscle and so can physically mix contents of ileum
3) microvilli - increase surface area for absorption
4) lots of capillaries - provides good bloody supply and maintain diffusion gradient

Question 5

what are lipids emulsified into

Answer 5

micelles