PQ : 5.12 - 5.15 + 5.20 - 5.22 Climate Change

Question 1

Answer 1

Question 2

Answer 2

Question 3

Answer 3

Question 4

Answer 4

Question 5

Answer 5

Question 6

Answer 6

The value of 3 indicates that activity has tripled

Question 7

Explain the effects of a temperature increase from 20 °C to 30 °C on the initial
rate of activity of catalase in the yeast cells.

Answer 7

Question 8

(iii) Explain what happens to the Q10 value between 40 °C and 50 °C.

Answer 8

Question 9

Leaf rust is a disease caused by a species of fungus. Leaf rust affects cereal crops
such as wheat.
Leaf rust yeast spreads through cereal crops when the humidity is high.
Discuss the possible impact of climate change on the effects of leaf rust on the
yield of wheat crops.

Answer 9

Question 10

*Pteropods are small free-swimming snails found in oceans throughout the world.
They are a food source for a variety of fish including salmon, mackerel and herring.
In 2011, the health of these snails was studied in the ocean around Hawaii.
A sample of these snails showed that 53% of them had damaged shells.
The photographs show a healthy snail and a snail with a damaged shell found in
the ocean around Hawaii.

The pH of sea water affects shell formation in these snails. The changes in carbon dioxide
concentration and pH have been recorded in oceans surrounding several islands.
These records are shown in the graphs.
Analyse the data to discuss the likely impact of increased carbon dioxide emissions
on fish populations in these oceans.
(6)

Answer 10

When CO2 is emmited it makes oceans more acidic which affetct the pH of the oceans.

Question 11

The Intergovernmental Panel on Climate Change (IPCC) has issued the following statement:
“Human influence on the climate system is clear, and recent anthropogenic emissions
of greenhouse gases are the highest in history. Recent climate changes have had
widespread impacts on human and natural systems.”
(a) Explain why anthropogenic emissions of greenhouse gases are affecting the climate.

Answer 11

Question 12

Answer 12

Null hyspothesis means - No differnce/No effect

Question 13

Answer 13

• If the expected value is not given then you calculate a mean using the values given
• Or you could use the control

Question 14

3 is the chi-squared value

Answer 14

• You do 3-1 = 2, so you use 2 degrees of freedom.
• In bio you uses always 0.05 significat level.
• Greater than 0.05 value then you reject
• Lower than 0.05 value then you accept

Question 15

(iii) Analyse the data to explain the predicted effect of climate change on the distribution of
ash trees.

Answer 15

Question 16

The golden snub-nosed monkey (Rhinopithecus roxellana) is endemic to high mountainous
regions of China.
This endangered species of monkey feeds on seeds.
Golden snub-nosed monkeys live in areas with very cold winters.
The seeds in their diet contain lipids and carbohydrates.
Climate change is reducing seed production by plants in their habitat.
Discuss the impact of climate change on the monkey population.

Answer 16

Question 17

Answer 17

Question 18

Lipoprotein lipase is an enzyme found in different tissues including the brain.
Lipoprotein lipase can be extracted from brain tissue to investigate the effect of temperature
on the rate of reaction of this enzyme.
(i) State what is meant by the term Q10 temperature coefficient.
(1)

Answer 18

Question 19

(ii) Devise an investigation to determine Q10 for an extract of lipoprotein lipase enzyme.
(5)

Answer 19

Question 20

Lipoprotein lipase is an enzyme found in different tissues including the brain.
The enzyme lipoprotein lipase is involved in the metabolism of lipids in the brain.
The effect of temperature on lipid metabolism in the brain tissue of a species of fish was
investigated.
The results of this investigation are shown in the table.
Comment on the effect of temperature on lipid metabolism in this species of fish.(3)

Answer 20

Question 21

Scientists are concerned that climate change may be affecting the Arctic environment and
the polar bears that live there.
In a study, scientists recorded the length of time ice was present each year in the sea
around the west coast of Spitsbergen, an island in the Arctic.
The graph shows the number of days each year when sea ice was present.
(i) Explain how the data could support a conclusion that climate change is occurring in the
Arctic.
(2)

Answer 21

Question 22

(ii) Explain why the data may not be useful for predicting future climate change.
(4)

Answer 22

Question 23

Answer 23

Question 24

Photosynthesis contributes to the productivity of ecosystems.
(i) State what is meant by the term ecosystem.
(1)

Answer 24

Question 25

Answer 25