(a)
Soon after starting physical activity the concentration of carbon dioxide in the blood increases.
[ 1 ]
(i)
Name the process inside cells that produces carbon dioxide.
[ 1 ]
[Maximum number: 6]
Bacteria are classified in the Prokaryote kingdom.
(a)
Samples were taken from the fermenter at frequent intervals and the number of live bacteria was determined. The results are shown in Fig. 1.2.
number of live bacteria /million per
Fig. 1.2
Describe and explain what happens to the number of live bacteria shown in the stages labelled A, B, C and D in Fig. 1.2.
[ 6 ]
[Maximum number: 3]
Homeostasis is the maintenance of a constant internal environment.
(a)
Energy is used to maintain body temperature.
State three other uses of energy in humans.
1
2
3
[ 3 ]
(a)
State three uses of energy in the human body.
1
2
3
[ 3 ]
[Maximum number: 1]
Commercial fishermen use ice to store the fish that they catch.
How does the ice keep the fish fresh?
A
Cells denature.
B
Decomposer activity decreases.
C
Decomposer activity increases.
D
Proteins denature.
[Maximum number: 3]
Fig. 2.1 shows a person sitting in a room. A thermometer shows the temperature of the room.
Fig. 2.1
(a)
Give three uses of energy in the body of the person in Fig. 2.1.
1
2
3
[ 3 ]
[Maximum number: 7]
Fig. 2.1 shows a person sitting in a room. A thermometer shows the temperature of the room.
Fig. 2.1
(a)
Give three uses of energy in the body of the person in Fig. 2.1.
1
2
3
[ 3 ]
(b)
The person leaves the room and runs very fast for 200 m . When the person stops running, his breathing rate and his heart rate remain high for several minutes.
Explain why the person's breathing rate and heart rate remain high.
[ 4 ]
[Maximum number: 1]
The diagram shows the apparatus at the beginning of an investigation into temperature change during the germination of seeds. The temperature at the start of the investigation was in both flasks.
After two days the temperature in flask 1 is . The temperature in flask 2 is .
Which characteristic of living organisms is shown in this experiment?
A
excretion
B
growth
C
reproduction
D
respiration
[Maximum number: 1]
An experiment is set up to investigate the uptake of oxygen by germinating seeds.
What happens to the levels of the coloured water at X and Y ?
X
Y
falls
rises
falls
unchanged
rises
falls
rises
unchanged
[Maximum number: 1]
What is the effect on germinating seeds of increasing the temperature from to ?
A
a decrease in the production of oxygen
B
a decrease in the respiration rate
C
an increase in the respiration rate
D
an increase in the transpiration rate