1.
State what is meant by a condensation reaction.
[1 mark]
- joins two molecules and releases water
JD SCIENCE
Module 2 Foundations in biology
Indicative marking points. Award marks for equivalent scientific or mathematical wording. Do not issue this sheet with the student worksheet.
2.
State what is meant by hydrolysis.
[1 mark]
- breaks a bond using water
3.
State what is meant by α-glucose.
[1 mark]
- hexose sugar used in starch and glycogen
4.
State what is meant by starch.
[1 mark]
- amylose and amylopectin
5.
State what is meant by cellulose.
[1 mark]
- β-glucose chains with hydrogen bonds
6.
State what is meant by a triglyceride.
[1 mark]
- glycerol + 3 fatty acids
7.
State what is meant by a phospholipid.
[1 mark]
- phosphate head + two fatty tails
8.
State what is meant by the primary structure of a protein.
[1 mark]
- sequence of amino acids
9.
State what is meant by an enzyme.
[1 mark]
- globular protein catalyst
10.
State what is meant by a nucleotide.
[1 mark]
- pentose + phosphate + base
11.
Grace is asked about a condensation reaction in a OCR Biology paper.
(a) [2 marks]
- makes polymers
(b) [3 marks]
- glycosidic, peptide, ester bonds
12.
Grace is asked about hydrolysis in a OCR Biology paper.
(a) [2 marks]
- digestion
(b) [3 marks]
- opposite of condensation
13.
Grace is asked about α-glucose in a OCR Biology paper.
(a) [2 marks]
- C₆H₁₂O₆
(b) [3 marks]
- differs from β-glucose at carbon 1
14.
Grace is asked about starch in a OCR Biology paper.
(a) [2 marks]
- plant energy store
(b) [3 marks]
- coiled, compact, insoluble
15.
Grace is asked about cellulose in a OCR Biology paper.
(a) [2 marks]
- plant cell walls
(b) [3 marks]
- high tensile strength
16.
Grace is asked about a triglyceride in a OCR Biology paper.
(a) [2 marks]
- energy store, insulation
(b) [3 marks]
- ester bonds
17.
A dipeptide is hydrolysed. How many water molecules are needed?
[3 marks]
- Final answer: 1
18.
A polypeptide has 50 amino acids. How many peptide bonds?
[3 marks]
- Final answer: 49
19.
Rf of a chromatogram spot 3.0 cm, solvent 7.5 cm
[3 marks]
- Final answer: 0.40
20.
Enzyme rate is 24 units at 20°C and 48 at 30°C. Q10
[3 marks]
- Final answer: 2
21.
A DNA strand is 12% A. Percentage T
[3 marks]
- Final answer: 12%
22.
If A=12% in DNA, percentage G
[3 marks]
- Final answer: 38%
23.
Grace carries out a OCR-style required practical linked to biological molecules. This is a typical OCR required-practical style question.
(a) [2 marks]
- Independent: the independent variable for this topic
- Dependent: the measured outcome
(b) [2 marks]
- keep all other variables constant
- so the test is fair / only one variable is changed
(c) [2 marks]
- repeat and calculate a mean / use a tighter method
24.
Grace carries out collecting valid data for biological molecules. This is a typical OCR required-practical style question.
(a) [2 marks]
- Independent: a chosen factor
- Dependent: a quantitative measurement
(b) [2 marks]
- calibrated instrument
- so the test is fair / only one variable is changed
(c) [2 marks]
- systematic error from zero error
25.
Grace carries out drawing a graph for biological molecules. This is a typical OCR required-practical style question.
(a) [2 marks]
- Independent: x-variable
- Dependent: y-variable
(b) [2 marks]
- same scale / same apparatus
- so the test is fair / only one variable is changed
(c) [2 marks]
- not drawing a line of best fit through the trend
26.
Grace carries out evaluating a method about biological molecules. This is a typical OCR required-practical style question.
(a) [2 marks]
- Independent: method change
- Dependent: precision / accuracy
(b) [2 marks]
- same sample size
- so the test is fair / only one variable is changed
(c) [2 marks]
- too few repeats
27.
Compare a condensation reaction with hydrolysis.
[4 marks]
- joins two molecules and releases water
- breaks a bond using water
- give one linked difference
28.
Compare hydrolysis with α-glucose.
[4 marks]
- breaks a bond using water
- hexose sugar used in starch and glycogen
- give one linked difference
29.
Compare α-glucose with starch.
[4 marks]
- hexose sugar used in starch and glycogen
- amylose and amylopectin
- give one linked difference
30.
Compare starch with cellulose.
[4 marks]
- amylose and amylopectin
- β-glucose chains with hydrogen bonds
- give one linked difference
31.
Apply your knowledge of a phospholipid to this situation: bilayer
[3 marks]
- bilayer
32.
Apply your knowledge of the primary structure of a protein to this situation: determined by DNA
[3 marks]
- determined by DNA