DP Biology (last assessment 2024)

Test builder »

Question 18M.2.SL.TZ1.2

Select a Test
Date May 2018 Marks available [Maximum mark: 7] Reference code 18M.2.SL.TZ1.2
Level SL Paper 2 Time zone TZ1
Command term Distinguish, Draw, State, Suggest Question number 2 Adapted from N/A
2.
[Maximum mark: 7]
18M.2.SL.TZ1.2
(a.i)

Distinguish between the structure of amylose and the structure of amylopectin.

[1]

Markscheme

amylose unbranched/helical while amylopectin branched / vice versa

(a.ii)

Suggest the reason for cellulose passing undigested through the human gut.

[1]

Markscheme

enzymes required to digest cellulose not present in the human gut OWTTE
OR
undigested cellulose provides bulk/fibre

(b)

Draw an annotated diagram to show how a peptide bond is formed.

[3]

Markscheme

a. correct structure of two amino acids 

b. H2O lost 

c. C from COOH of one links to N of NH2/NH3+ from the other 

d. correct labelling of the peptide bond

e.g.

(c)

State two structural features that differ between RNA and DNA.

[2]

Markscheme

a. number of strands
OR
(usually) only one strand in RNA/two strands in DNA 

b. base composition
OR
uracil only in RNA / thymine only in DNA 

c. type of pentose
OR
ribose only in RNA / deoxyribose only in DNA

Syllabus sections