Biology

1. Below is the chair confirmation of the molecule, glucose
2. a) Based on the number of molecules,

what type of saccharide is glucose?

(1 mark)

 

1. b) Glucose has two isomers, what does

the word isomer mean?

(2 marks)

 

 

1. c) Draw the structural formulae of and

name the two isomers of glucose

(6 marks)

 

 

1. d) Sucrose is formed from one molecule

of glucose and another simple sugar,

which one?

(1 mark)

 

1. e) Draw and name the bond that joins

simple sugars together in

polysaccharides like sucrose.

(2 marks)

 

 

 

2. This molecule is an example of a lipid

 

 

1. a) Looking at the structure,

identify the type of lipid

pictured, explaining your

reasons.

(3 marks)

 

1. b) Describe the difference

between a saturated fatty acid

and an unsaturated fatty acid,

and deduce which group the

pictured lipid belongs to.

(3 marks)

1. c) Name the type of reaction that

forms this type of lipid

(1 mark)

1. d) Describe the THREE main uses

of this type of lipid within the

body, and suggest why its

structure lends itself to these

uses

(4 marks)

 

3. Draw the general structure of an amino acid, identifying the different

parts (6 marks)

 

 

 

3. Below is an example of a polypeptide

 

1. a) Identify the area called the

“peptide bond”

(1 mark)

1. b) In what sort of chemical

reaction are these bonds

formed?

(1 mark)

5. Discuss the FIVE levels of structural organisation in proteins, providing an

example of each where possible.

(12 marks)

 

6. The diagram below shows part of a messenger RNA (mRNA) molecule.

 

 

1. a) i) How many codons are

shown in this section of

mRNA?

(1 mark)

 

 

1. ii) What is specified by a

sequence of codons in an

mRNA molecule?

(1 mark)

 

 

 

1. b) A tRNA molecule carries a complementary sequence for a particular

codon.

 

1. i) Write out the

complementary sequence

for the FIRST codon in the

mRNA sequence.

(1 mark)

 

1. ii) What is the role of tRNA

molecules in the process of

protein synthesis?

(3 marks)

 

 

7. The diagram below outlines protein synthesis in a normal cell.

 

 

1. a) Name stages 1 and 2

(2 marks)

 

1. b) Where does stage 2 take

place?

(2 marks)

 

1. c) Identify the codon that

initiates stage 2

(1 mark)

8. Below is a graph showing the effect of temperature on the rate of a

biological reaction catalysed by an enzyme.

1. a) Account for the shape of

this graph explaining the

key features of the slopes

and the area signified by

the red circle.

(5 marks)

 

 

 

1. b) Produce a rough graph to

represent the general effect

of change in pH on the rate

of an enzyme catalysed

reaction.

(4 marks)

 

 

1. c) Explain the key features of

this graph and the

reasoning behind why it is

shaped like this.

(3 marks)

 

 

9. The diagram below shows four molecules of water.
10. a) What type of bond is “A” on

the diagram?

(1 mark)

 

1. b) Why are water molecules

described as dipolar?

(4 marks)

1. c) Water has a high specific heat

capacity. Why is this important

for organisms that live in

water?

(2 marks)

 

10. Below are the general structures of prokaryotic and eukaryotic cells.
11. a) Identify the parts labelled A, B

and C

(3 marks)

 

 

1. b) Explain the function of the

parts labelled A, B and C

(3 marks)

 

 

1. c) Part c is present in both

eukaryotic and prokaryotic

cells, how do they differ

between the two?

(1 mark)

 

 

1. d) Sketch simple cell diagrams for

a typical plant cell and a typical

animal cell, and discuss the

differences in terms of: –

 Cell walls

 Plastids

 Lysosomes

 Centrioles

 Vacuoles

(14 marks)

11. The diagram below shows the structure of a chloroplast, as seen using an

electron microscope.

1. a) Identify the parts labelled A, B

and C

(3 marks)

 

 

 

 

1. b) The length of this chloroplast

is 2.5μm. Calculate the

magnification of this diagram.

Show your working out.

(3 marks)

12.The diagrams below show chromosomes during stages in the process of

mitosis.

 

 

1. a) Write down the letters as a list

in the order in which these

stages occur.

(1 mark)

 

 

 

1. b) Give two ways in which meiosis

differs from mitosis

(2 marks)

 

 

 

1. c) Name and briefly describe the

stages of mitosis including the

immediately preceding and

subsequent stages

(12 marks)

13. Below are the reproductive systems of male and female humans.
14. a) Give the functions of: –
15. The testes
16. The ovaries

iii. The penis

1. The vagina

(4 marks)

 

 

 

1. a) Briefly describe the processes of
2. Spermatogenesis (2

marks)

1. Oogenesis (3 marks)

 

Classification, Biodiversity, Exchange & Transport

1. The binomial classification system is widely used to classify organisms

based on different levels of relationship.

1. a) Name the EIGHT taxa used in

binomial classification

(8 marks)

1. b) Using this binomial system of

classification, identify the eight

different tax for the polar bear

(8 marks)

 

 

 

 

1. c) What are the FIVE kingdoms?

(5 marks)

2. Charles Darwin’s book “On the Origin of the Species by means of

natural selection” changed our perceptions of evolution in November

1860. a) Describe the FOUR main

observations of Darwin’s

theory of natural selection

(4 marks)

1. b) What are the THREE types of

natural selection? Describe and

give an example of each.

(12 marks)

 

1. c) Outline the difference between

allopatric and sympatric

speciation

(2 marks)

3. The biodiversity index, D, can provide an insight into the health of an

ecosystem and the various species within it. We can calculate the

biodiversity index using the following formula: –

An individual count of species in a small rock pool ecosystem is undertaken

and population numbers of its various species recorded, producing the

following table: –

1. a) Calculate the diversity index, D

for this rock-pool community.

Show your working

(6 marks)

 

 

 

1. b) What is the maximum

diversity for this community

and what does your value for

D say about the diversity here?

(3 marks)

4. Below are two different sized cubes that represent small organisms

and large organisms respectively.

1. a) Calculate for both cubes:
2. i) The area of a face
3. ii) The total surface area

iii) The volume

1. iv) The surface area: volume

ratio

(8 marks)

 

 

 

1. b) Outline the pros and cons of

having a low surface area to

volume ratio as is the case with

large organisms.

(2 marks)

 

 

1. c) Suggest how the human lungs

are adapted for effective gas

exchange, in terms of surface

area distance and

concentration gradient

(3 marks)

 

5. Explain what is meant by the following terms

 

1. a) Osmosis

(3 marks)

 

 

 

1. b) Facilitated Diffusion

(3 marks)

 

 

 

1. c) Diffusion

(3 marks)

 

 

 

1. d) Active transport

(3 marks)

6. Mammals and fish have very different environments in which to thrive

and so their systems for gas exchange have to be adapted in

completely different ways.

 

1. a) Compare and contrast the gas

exchange systems in mammals

and fish

(6 marks)

 

 

1. b) Explain the gas exchange

system of insects, and how

they are adapted for their

lifestyle.

(4 marks)

7. Below is a diagram of a cross section of a plant leaf.

Identify and give the functions of

parts A and B

(4 marks)

8. The diagram below shows a section of a human heart at a

precise stage in the cardiac cycle.

1. a) Name the stage of the cardiac

cycle shown in the diagram

(1 mark)

 

 

1. b) Give two reasons for your

answer

(2 marks)

1. c) Name and give a function for

each of the parts A and B as

shown on the diagram

(4 marks)

9. The graphs below show the changes in pressure in the aorta and in the

left and right ventricles of the heart, during the cardiac cycle. The

figure 0 on the ‘time’ axis indicates the start of atrial contraction.

1. a) What do you notice about

the changes in pressure in

the left ventricle compared

with the changes in the right

ventricle?

(4 marks)

 

 

 

1. b) Compare the changes in the

pressure in the aorta with

those in the left ventricle

and write down your

observations.

(3 marks)

 

1. c) Cardiac muscle is described

as myogenic. Explain how

the cardiac cycle is

coordinated within the heart

– so here you need to think

about the underlying

processes.

(4 marks)

 

 

 

1. d) Describe the differences

between the double and

single circulatory systems

(3 marks)

 

10. Name FIVE risk factors for atherosclerosis and explain your reasoning.

(10 marks)

11. Explain why the haemoglobin of a foetus has a greater affinity for

binding with oxygen than an adult’s haemoglobin.

(3 marks)

12. The uptake of water by a leafy shoot can be investigated using

apparatus like that shown in the diagram below.

1. a) What is the name of this piece

of apparatus?

(1 mark)

 

 

 

1. b)
2. i) Name the assumption

made when this

apparatus is used to

investigate the rate of

transpiration?

(1 mark)

 

1. ii) Name two precautions

that need to be taken in

order to make sure this

experiment works

correctly. (2 marks)

Using this apparatus, four experiments were carried out with the

same shoot in the following order:

 

A: Still air, leaves untreated

B: Moving air, leaves untreated

C: Still air, lower surface of leaf covered with grease

D: Moving air, lower surface of leaf covered with grease

 

The variables of temperature and light intensity were kept constant

during the investigation and the results are shown in the following

graph:

The mean rate of water uptake during experiment A was 3.2 mm3 per

minute and the cross-sectional area of the bore of the capillary tube is 0.8

mm2.

 

1. c) Now calculate the mean rate of

water uptake by the shoot

during experiment B. Show

your working out.

(3 marks)

 

 

1. d)
2. i) Explain the effect of

moving air on the rate of

water uptake in

experiment B.

(3 marks)

1. ii) Give an explanation for

the different effects of

moving air in

experiments B and D.

(3 marks)

Unit 2

Energy for Biological Processes, Microbiology & Pathogens

2. a) In recall the chemical word equation

for aerobic respiration

(2 marks)

 

1. b) In which organelle within cells does

respiration take place?

(1 mark)

 

1. c) Summarise the steps involved in

glycolysis

(4 marks)