IB DP Biology- C1.1 Enzymes and metabolism- IB Style Questions For SL Paper 2 - FA 2025
▶️ Answer/Explanation
(a)
Function of the cell: This pancreatic cell secretes digestive enzymes, which are proteins, into the small intestine.
Relevant organelles and their roles:
- Nucleus:
a. Contains genes that are transcribed to mRNA for enzyme production. - Rough Endoplasmic Reticulum (RER):
b. Has ribosomes on its surface that synthesize proteins (digestive enzymes) from mRNA instructions. - Mitochondria:
c. Produces ATP, supplying energy needed for protein synthesis and secretion. - Golgi Apparatus:
d. Modifies and packages enzymes into vesicles. - Vesicles:
e. Transport enzymes to the plasma membrane for secretion via exocytosis.
(b) (i) Lipase catalyzes the hydrolysis (breakdown) of lipids/triglycerides into fatty acids and glycerol.
(ii) Protease
Markscheme:
(a)
a. genes for digestive enzymes are transcribed in the nucleus;
b. rough ER/ribosomes produces/synthesizes enzymes/proteins;
c. mitochondrion produces ATP to provide energy for protein/enzyme production;
d. Golgi apparatus/body processes enzymes/proteins
OR
Golgi apparatus/body packages enzymes into vesicles;
e. vesicles carry enzymes to (plasma) membrane
OR
vesicles secrete enzymes by exocytosis;
(b)
(i) digestion/hydrolysis/break down of lipids/fats/triglycerides (into fatty acids and glycerol);
(ii) amylase / endopeptidase / trypsin / trypsinogen / protease;