EduNinja
[Maximum number: 1]

All living organisms are placed into groups according to their features. Myriapods are one of the main groups of arthropods.

(a)

Fig. 1.4 is a photograph of the myriapod, Apheloria virginiensis.

Fig. 1.4

Fig. 1.4

[ 1 ]
(i)

A. virginiensis releases the poison cyanide when it is attacked by predators. Cyanide stops enzymes in the mitochondria from functioning.

Suggest why cells die if the mitochondria do not function.

[ 1 ]
(a)

Some students were studying the activity of yeast. They made a fact file, as shown in Fig. 1.1.

Fig. 1.1

Fig. 1.1

[ 1 ]
(i)

State the process that occurs in mitochondria to provide energy for yeast cells.

[ 1 ]
[Maximum number: 1]

In which part of the cell is oxygen used to release energy from nutrient molecules?

A

mitochondrion

B

ribosome

C

rough endoplasmic reticulum

D

vesicle

[Maximum number: 2]

Fig. 2.1 shows a person sitting in a room. A thermometer shows the temperature of the room.

Fig. 2.1

Fig. 2.1

(a)
(i)

Name the process carried out by the person in Fig. 2.1 that releases energy.

[ 1 ]
(ii)

State the balanced chemical equation that describes this process.

[ 1 ]
(a)

Fig. 2.1 shows the transfer of materials between blood and tissues.

Fig. 2.1

Fig. 2.1

[ 2 ]
(i)

Explain why cells need oxygen.

[ 2 ]
[Maximum number: 6]

Fig. 2.1 shows a person sitting in a room. A thermometer shows the temperature of the room.

Fig. 2.1

Fig. 2.1

(a)
(i)

Name the process carried out by the person in Fig. 2.1 that releases energy.

[ 1 ]
(ii)

State the balanced chemical equation that describes this process.

[ 1 ]
(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: 6]

Fig. 2.1 shows a cross-section of a human heart.

Fig. 2.1

Fig. 2.1

(a)

Fig. 2.3 shows how the body uses aerobic and anaerobic respiration during the first 120 seconds of vigorous physical activity. Between 0 and 20 seconds, the body also uses stored energy.
percentage of energy released

Fig. 2.3

Fig. 2.3

[ 6 ]
(i)

Describe the data shown in Fig. 2.3.

[ 4 ]
(ii)

State the balanced chemical equation for aerobic respiration.

[ 2 ]
[Maximum number: 1]

What is the correct equation for aerobic respiration?

A

6CO2+6H2O→C6H12O6+6O26 \mathrm{CO}_{2}+6 \mathrm{H}_{2} \mathrm{O} \rightarrow \mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}+6 \mathrm{O}_{2}

B

C6H12O6+6CO2→6O2+6H2O\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}+6 \mathrm{CO}_{2} \rightarrow 6 \mathrm{O}_{2}+6 \mathrm{H}_{2} \mathrm{O}

C

C6H12O6+O2→CO2+H2O\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}+\mathrm{O}_{2} \rightarrow \mathrm{CO}_{2}+\mathrm{H}_{2} \mathrm{O}

D

C6H12O6+6O2→6CO2+6H2O\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}+6 \mathrm{O}_{2} \rightarrow 6 \mathrm{CO}_{2}+6 \mathrm{H}_{2} \mathrm{O}

[Maximum number: 1]

The apparatus shown was used to investigate aerobic respiration in seeds.
The apparatus was placed in a dark room.

Question image

All environmental conditions were kept constant.
What will happen in the apparatus?

gas taken in
by the seeds

gas absorbed
by the chemical
in the wire mesh

direction of
movement of the
coloured liquid

carbon dioxide

oxygen

towards the seeds

carbon dioxide

oxygen

away from the seeds

oxygen

carbon dioxide

towards the seeds

oxygen

carbon dioxide

away from the seeds

[Maximum number: 1]

Aerobic respiration involves the break down of glucose.

C6H12O6+…x…O2→…y…H2O+…z…CO2+ energy \mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}+\ldots \mathrm{x} \ldots \mathrm{O}_{2} \rightarrow \ldots \mathrm{y} \ldots \mathrm{H}_{2} \mathrm{O}+\ldots \mathrm{z} \ldots \mathrm{CO}_{2}+\text { energy }

Which values for x, y and z balance the equation?

x

y

z

6

4

6

6

6

6

6

12

6

12

12

12

0