enzymes and digestion

Question 1

Define Digestion

Answer 1

Digestion is breaking down of the food by mechanical and chemical mean, into smaller components to be absorbed into the bloodstream

Question 2

Define absorption

Answer 2

Absorption is the taking in of soluble nutrients into the body cells

Question 3

Define assimilation

Answer 3

Assimilation is the process in cells where the soluble nutrients are used to make larger molecules.

Question 4

Digestion of starch

Answer 4

Starch is digested into glucose, in two stages. First it begins in the mouth by Salivary amylase, where only a small proportion of it is actually hydrolysed since the enzyme gets denatured.And in the pancreas by pancreatic amylase, where it is digested to maltose. Then on the epithelial cells of the ileum, where maltase (membrane bound dissacharideases enzyme) hydrolyses it to glucose by breaking glycosidic bonds

Question 5

Define hydrolysis

Answer 5

Hydrolysis is the breaking down of bonds between molecules with the use of water

Question 6

List two structures that produce amylase

Answer 6

Pancreas & Salivary glands

Question 7

Digestion of disaccharides

Answer 7

Disaccharides

Question 8

List the final product of digestion of starch in the gut

Answer 8

@-glucose

Question 9

List the enzymes produced by the epithelium cells lining of the ileum

Answer 9

Maltase, sucrose, Lactase

Question 10

Type of bonds are broken in the digestions of carbohydrates

Answer 10

Glycosidic bonds

Question 11

What happens in the digestion of proteins

Answer 11

3 types of enzymes act to hydrolyse the proteins.

Endopetides then Exopeptides and then Dipeptidases

Question 12

Function of Endopetidases

Answer 12

The enzymes hydrolyses peptide bonds within the amino acids in the central region/middle of a polypeptide chain. Breaking it into two or more smaller peptides

Question 13

Function of exopeptidases

Answer 13

The enzyme hydrolyses the peptide bonds at the ends of the protein molecules

Question 14

Function of dipeptidases

Answer 14

hydrolyses the peptide bonds between a dipeptide (two amino acids)

Question 15

Where does digestion of proteins occur

Answer 15

Proteins are first broken down in the stomach, the process then continues in the duodenum and it is fully digested in the ileum

Question 16

What digests lipids?

Answer 16

The pancreatic enzyme lipase and the action of bile salts

Question 17

What are lipids hydrolysed into?

Answer 17

Lipids are hydrolysed into fatty acid and monoglycerides. As the ester bonds between the fatty acid molecules and the glycerol molecule is broken apart.

Question 18

Features of the ileum that maximise absorption

Answer 18

The ileum wall is covered in tiny vili, the vili have thin walls and are heavily surrounded by tiny capillaries . THe epithelial cells themselves have tiny microvilli.