- Plants that live in the desert are adapted to survive in a dry climate. How are these adaptations advantageous to plants living in the desert:
- a shallow root system spread out over a large area?
- bulb-like roots growing deep within the soil?
- leaves covered in a layer of wax?
- A group of students was asked to investigate a food chain in a small orchard.
The table below shows estimates of the population and biomass of three main organisms found in the orchard.
Organism |
Number in orchard |
Mean mass (g) |
Biomass in population (g) |
Fox |
5 |
6000 |
30000 |
Mice |
100 |
25 |
2500 |
Apples |
500 |
250 |
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- Calculate the biomass of the apple population. Show clearly how you worked out your answer.
- Sketch a pyramid of biomass for the information in the table.
- Foxes eat mice. The biomass of the mice population is much lower than that of the fox population. Explain why.
- The human body contains approximately 80 million alveoli.
- Give three features of alveoli that make it good for gaseous exchange.
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- Oxygen passes from the air into the blood. What is this process called?
- Large amounts of oxygen can enter the blood due to the process of breathing. Explain how breathing achieves this.
- Lichens are sensitive to sulfur dioxide levels in the air. They are used as indicators of how much air pollution there is in a particular area. Usually, air pollution is worse in towns and cities than in the countryside.
A group of environmentalists decided to investigate the relationship between the species of lichen
growing on trees and their distance from the centre of a town.
On a map they drew a transect line from the centre of the town into the countryside.
The marked out sites to examine every 250 metres.
At each site they examined the trees and walls to a height of 3 metres.
The table of their results is below.
Lichen species |
Distance range from the town centre (km) |
Xanthoria |
0 – 2 |
Lecanora |
1 – 5 |
Parmelia |
2 – 8 |
Evernia |
7 – 8 |
- How could the environmentalists have obtained more accurate results? Provide one way.
-
- Which lichen species was found over the shortest range?
- Which species grows in areas with the least pollution?
- One environmentalist stated: ‘You can see the amount of sulfur dioxide present in the air due to the amount of Lecanora growing.’
Provide two reasons why this conclusion is not valid.
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- What organ in the body monitors the amount of glucose in the blood?
- Insulin prevents high amount of glucose in the blood. Describe how it does this.
- There are two types of diabetes.
-
People who have Type 1 diabetes produce only a little or no insulin.
People who have Type 2 diabetes contains cells that do not respond to insulin.
Connect the type of diabetes to the treatment.
Type 1 Attention to diet only
Type 2 Attention to diet and insulin injections
Insulin injections only
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- Complete the sentence using one of the words provided below.
lipid protein carbohydrate
Insulin is a hormone and a type of ____________.
- Insulin is controlled by a small section of DNA. What is this small section of DNA called?
ANSWERS
-
- Answers include:
- water uptake increased
- able to collect water over a larger surface area
- Answers include:
Answers not accepted:
- any reference to nutrients or food allowing for water to be taken up faster
- water can be stored
- plant more stable
- provides safety from predators
Answers not accepted:
- water absorption from the soil
- water loss/evaporation is reduced
- keeps the plant cool
- heat is reflected
Answers not accepted:
- light reflected
-
-
- 500 x 250 = 125000
- Remember you only need to sketch so it doesn’t have to be accurate. However, you need to use the figures from the biomass column.
- Check how many marks are awarded so that you know how many points to make. Answers include:
- respiration by the fox which leads to carbon dioxide being lost
- the fox excretes/produces faeces/produces urine
- not all the mice are eaten by the foxes/some mice are eaten by other organisms
-
Answers not accepted:
- any reference to size/mass/or the number of organisms
- respiration doesn’t use or produce energy
- some mice die
- any reference to movement/heat/growth
-
- Answers include:
- a large surface area
- only once cell thick so it’s only as short distance from the air to the blood
- they have a good blood supply due to the extensive capillary network
- Answers include:
Answers not accepted:
- moist surface
- Correct: diffusion
Incorrect: gaseous exchange is not acceptable
- Answers include:
- more oxygen/air is brought into the lungs/alveoli which keeps the level of oxygen high in the alveoli
- it maintains the concentration difference between the blood and the alveoli with the oxygen concentration in the alveoli higher than that in the blood
-
- Answers include:
- use a shorter distance between each sample taken
- take a sample of a greater height
- specify how large each site is
- Answers include:
Answers not accepted:
- repeating the investigation
- repeating measurements
- using a longer transect
- Evernia
- Evernia
- Lecanora doesn’t grow along the whole of the transect orLecanora doesn’t grow in the town centre/countryside
- Lecanora grows in a particular range of sulfur dioxide concentrations or Lecanora grows in a limited range of sulfur dioxide
- Lecanora growth could be affected by other factors
- the sulfur dioxide concentration wasn’t measured
- the amount of Lecanora wasn’t measured
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- Pancreas
- Correct answers:
- it increases the movement of glucose into the cells/organs
- it allows glucose to be converted into glycogen/fat
-
Incorrect answer: don’t use hybrid spellings of glycogen in your answer
- Only choose one answer
Type 1 – Attention to diet and insulin injections
Type 2 – Attention to diet only
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- Protein
- Gene or allele
This the end of the paper – Well Done!
Head back to GCSE Biology Revision to carry on with your revision.
Keep going! All of your hard work will pay off in the end!