Biology · Oct / Nov 2022 · Paper 42 · Question 2

one mark per row

number

organ that

identifying

product enzyme

secretes the

the organ

substrate

or enzyme

on Fig.

products 2.1

salivary

amylase

1

starch

maltose

pepsin /

stomach /

amino 3

protein

gastric gland

acid(s) fatty fat / lipid

lipase

pancreas

4

acids and

glycerol small

intestine

maltase

5

maltose

glucose

/ ileum

any three from:

1

ref to hydrochloric acid in the stomach ;

2

kills, bacteria / pathogens (in food) ;

3

denatures enzymes in, bacteria / (harmful) microorganisms (in food) ;

4

provides, acid / suitable / low / optimum / best, pH for, pepsin / protease / (digestive) enzymes ;

5

AVP ; e.g. activation of pepsinogen

(re)absorbs, water / ions / vitamins ;

AVP ; e.g. fermentation of indigestible (food) matter by bacteria

any six from:

1

mechanical / physical, digestion / breakdown ;

2

(decrease particle size) increase surface area (of food for chemical digestion) ;

3

for (named) enzyme (activity) ;

4

any further detail of enzyme activity ;

5

chewing / crushing / grinding / AW, in the mouth / by teeth ; A mastication

6

incisor / canine, (teeth) for cutting food / AW ;

7

(pre)molar (teeth), crush food / AW ;

8

mixing of saliva with food / formation of bolus of food for swallowing ;

9

churning action / formation of chyme / AW, of stomach (3) ; 10 ref to action of muscles in the stomach (wall) ;

11 emulsification by bile ;

12 occurs in, small intestine / duodenum / ileum (5) ;

13 described as bile (salts) break(s) fat globules into smaller pieces / large fat droplets into small(er) droplets / AW ;