| Date | May 2018 | Marks available | 2 | Reference code | 18M.2.SL.TZ1.2 |
| Level | Standard level | Paper | Paper 2 | Time zone | Time zone 1 |
| Command term | State | Question number | 2 | Adapted from | N/A |
Question
Distinguish between the structure of amylose and the structure of amylopectin.
Suggest the reason for cellulose passing undigested through the human gut.
Draw an annotated diagram to show how a peptide bond is formed.
State two structural features that differ between RNA and DNA.
Markscheme
amylose unbranched/helical while amylopectin branched / vice versa
enzymes required to digest cellulose not present in the human gut OWTTE
OR
undigested cellulose provides bulk/fibre
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.
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
Examiners report
Syllabus sections
- 16N.1.SL.TZ0.7: The diagram shows a molecular structure. Which type of molecule is shown? A. Amino acidB....
- 18M.1.SL.TZ1.11: Nucleic acids are polymers of nucleotides. What parts of nucleotides are joined together in...
- 17N.1.SL.TZ0.10: For which discovery about DNA do Watson and Crick receive credit? A. DNA is the molecule...
- 16N.1.SL.TZ0.10: What is a similarity between DNA and RNA? A. Both are polymers of nucleotides.B. Both are...
- 17M.1.SL.TZ2.27: The bacterium Neisseria gonorrhoeae causes infections related to the human reproductive...
- 18M.2.SL.TZ2.2b.i: Explain how model making helped Watson and Crick to establish the structure of DNA.
-
18M.2.SL.TZ2.2a:
Label the parts of the DNA diagram indicated by I, II, III and IV.
-
22M.2.HL.TZ1.8a:
Draw a labelled diagram to show the structure of a single nucleotide of RNA.
-
22M.2.SL.TZ1.7a:
Draw a labelled diagram to show the structure of a single nucleotide of RNA.
- 17M.1.SL.TZ1.21: Cladograms can be created by comparing DNA or protein sequences. The cladogram on the left is...
- 21M.1.SL.TZ1.9: The hydrolysis of a pure sample of an organic molecule produces a pentose sugar, thymine,...
-
22M.2.HL.TZ2.5a.ii:
Explain how the two strands of the DNA double helix are held together.
-
20N.2.SL.TZ0.5a:
Draw a molecular diagram of alpha-D-glucose.
- 19M.2.HL.TZ2.7a: Distinguish between the structures of DNA and RNA.
- 17M.2.HL.TZ1.1f.ii: Suggest a reason for the greater expression of the gene for the urea transporter after an...
-
20N.2.SL.TZ0.4a:
Sketch the complementary strand to complete the section of a DNA diagram.
- 17M.2.SL.TZ1.1c: Estimate how much smaller drilled oysters raised in seawater at a high CO2 concentration were...
- 22M.1.SL.TZ1.9: A molecule of DNA is found to contain 200 guanine bases, representing 25 % of the total...
- 22M.1.SL.TZ2.11: What is a function of the enzyme helicase? A. It coils DNA up into a double helical...
- 19M.1.HL.TZ1.7: What is common to RNA and DNA? A. Thymine B. Nitrogenous bases C. Histones D. Deoxyribose
- 17M.2.SL.TZ1.5a: Outline how translation depends on complementary base pairing.
- 19N.2.HL.TZ0.6a: Draw the structure of a section of DNA showing all possible bases.
-
18M.2.HL.TZ1.6c:
Hydrogen bonds can exist both within and between molecules in living organisms and have an impact on their structure and function. Explain the importance of hydrogen bonding for living organisms.
