1
1
The diagram shows a protease molecule catalysing the break down of a protein molecule.
P
Q
R
S
What are the parts labelled P, Q, R and S?
enzyme
product
substrate
active site
A
P
Q
R
S
B
R
S
P
Q
C
S
P
Q
R
D
S
R
Q
P
[1]
[Total: 1]
2
List the three chemical elements that are found in fats.
..................................................................................................................................................
[1]
[Total: 1]
3
Urine contains urea.
State where urea is produced in the body.
..................................................................................................................................................
[1]
[Total: 1]
2
4
Which diagram shows the structure of DNA?
A
B
C
D
A
C
A
T
A
C
A
G
A
C
A
T
A
C
A
T
T
G
T
A
T
G
T
G
C
A
C G
C
A
C
G
G
T
G C
G
T
G
C
A
C
A
T
A
C
C
T
G
T
G C
G
T
G
C
[1]
[Total: 1]
5
The table shows the results of some food tests.
Which row shows a food containing both protein and starch?
Benedict’s
solution
biuret test
ethanol
iodine
solution
A
blue
blue
clear
blue-black
B
blue
purple
clear
blue-black
C
red
blue
cloudy
brown
D
red
purple
cloudy
brown
[1]
[Total: 1]
6
Which statement about enzymes is correct?
A
Enzymes become part of the product.
B
Lowering the pH always slows down the reaction rate.
C
Raising the temperature always increases the reaction rate.
D
The specificity of an enzyme depends on the shape of its active site.
[1]
[Total: 1]
3
7
The diagram shows some of the stages in the reproduction of the bacterium Escherichia coli.
loop of DNA
original bacterial cell
bacterial cell expands to a critical length
and a copy of DNA is synthesised
daughter cells are formed
daughter cells grow
Complete the sentences about the cells in the diagram.
The DNA is in the form of a double ............................................... . The DNA is copied so
that the number of loops of DNA after cell division is ............................................... in each
daughter cell. The daughter cells are genetically ............................................... to the original
cell.
[3]
[Total: 3]
8
State the word equation for aerobic respiration.
+
→
+
[2]
[Total: 2]
4
9
Dialysis tubing is an artificial membrane, which is similar to the lining of the intestine.
A student investigated the diffusion of glucose through dialysis tubing by using the apparatus shown
in the diagram.
The student took samples of the water outside the dialysis tubing at 5 minute intervals and tested
the samples with Benedict’s solution. The results are shown in the table.
time / minutes
results of the Benedict’s tests on the water outside
the dialysis tubing
0
blue
5
green
10
yellow
15
red
Describe and explain the results shown in the table.
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
[3]
[Total: 3]
5
10 Seed banks are used to conserve endangered plant species.
The diagram shows some of the steps involved in managing a seed bank.
seeds are collected from
many populations of
each species
seeds are checked using
X-rays
seeds are stored at low
temperatures in the
seed bank
a small sample of seeds
is germinated
Seeds stored at low temperatures have very low respiration rates.
Explain why.
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
[2]
[Total: 2]
6
11
Yeast is used in the production of ethanol to manufacture a type of biofuel.
The diagram is a flow chart of the process.
Yeast is used in process U. Complete the balanced chemical equation for anaerobic respiration in
yeast.
................................. →
...........C2H5OH
+
..................
[2]
[Total: 2]
12 Complete the sentences about enzymes by filling in the gaps.
Use words or phrases from the list.
catalysts
hormones
prevent
protein
speed up
not changed
slow down
used up
Enzymes are made of ......................................... molecules.
They function as ......................................... which means that they .........................................
chemical reactions.
[3]
7
[Total: 3]
13 Researchers in Chile investigated the rate of respiration in crickets.
They investigated the effect of temperature and body mass on the rate of respiration. They measured
the rate of oxygen consumption in crickets with different body masses, at different temperatures.
The researchers’ results are shown in the graph below.
State two conclusions that can be made from the data in the graph and support each conclusion
with evidence from the graph.
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
[4]
[Total: 4]
8
14 Doctors wanted to investigate the effect of exercise on the excretion of salts.
They collected urine from people before and after running a long distance on a hot day.
The results of their investigation are shown in the table.
average volume of urine / cm
3
average concentration of sodium in urine /
3
mmol per dm
before running
after running
1156.0
569.0
85.6
78.2
Calculate the percentage decrease in the average sodium concentration after running compared
with before running.
Give your answer to one significant figure.
Space for working.
.............................................. %
[3]
[Total: 3]
15 Organisms carry out aerobic respiration to release the energy they need to stay alive.
State three processes that humans carry out using this released energy.
1 ................................................................................................................................................
2 ................................................................................................................................................
3 ................................................................................................................................................
[3]
[Total: 3]
9
16 The table shows some comparisons between a human and a mouse.
feature
human
mouse
body mass / kg
60.0
0.025
kidney mass / g
320.0
0.310
1.5
0.005
water reabsorption / dm per day
179.0
0.168
salt filtration rate / g per day
580.0
0.556
salt reabsorption / g per day
575.0
0.551
3
water intake / dm per day
3
The table shows that water is reabsorbed in the kidneys of both humans and mice.
State the name of the process that mammals use to reabsorb water.
..................................................................................................................................................
[1]
[Total: 1]
17 The diagram shows an enzyme with its substrate and product molecules.
Q
P
R
S
Which form an enzyme-substrate complex?
A
P and Q
B
Q and R
C
R and S
D
S and P
[1]
[Total: 1]
10
18 Why does excessive heat decrease enzyme activity?
A
It changes the shape of the active site.
B
It changes the shape of the substrate and product molecules.
C
It increases the force of collisions between substrate and product molecules.
D
It increases the kinetic energy of the substrate molecules.
[1]
[Total: 1]
19 A longitudinal section of the kidney and some associated structures have been labelled.
Which labelling is correct?
A
B
cortex
cortex
renal artery
renal vein
ureter
ureter
medulla
medulla
C
D
medulla
cortex
medulla
renal artery
ureter
ureter
renal artery
cortex
[1]
[Total: 1]
11
20 The diagram shows some of the structures involved in excretion.
Complete the diagram by labelling the structures in the spaces provided.
Choose structures from the list:
bladder
bronchus
heart
liver
pancreas
trachea
ureter
urethra
lung
[5]
[Total: 5]