Combined Science A (Gateway) · OCR J250 · Biology Paper 7 · Higher · November 2020
Table 1.1 shows the classification of non-diabetic, pre-diabetic and type 2 diabetes based on their blood glucose levels.
Table 1.2 shows measurements of blood glucose levels taken from 4 people.
Which row in Table 1.2 shows a person who is a pre-diabetic ?
[1]
A student investigates the rate of diffusion using blocks of agar.
The diagram shows one of the blocks of agar they use.
The block has a surface area of 40 cm2.
What is the surface area to volume ratio of this block of agar?
A 1: 2
B 1: 2.5
C 2: 1
D 2.5: 1
[1]
The diagram shows cells from a plant.
What is the function of these cells?
A Produce sucrose
B Take in water from the soil
C Transport sucrose to the roots
D Transport water up the stem
[1]
Which of these statements about proteins is correct?
A Proteins are monomers made from polymers called amino acids.
B Proteins are polymers made from monomers called amino acids.
C Proteins are monomers made from polymers called fatty acids.
D Proteins are polymers made from monomers called fatty acids.
[1]
What are the product(s) of anaerobic respiration in animals?
A Alcohol
B Alcohol and carbon dioxide
C Lactic acid
D Lactic acid and carbon dioxide
[1]
The diagram shows a sensory neurone.
What is the part labelled X ?
A Axon
B Dendrite
C Cell body
D Nucleus
[1]
Look at the table.
| Glucagon released | Insulin released | Action of liver | |
| A | yes | no | glucose converted to glycogen |
| B | no | yes | glycogen converted to glucose |
| C | yes | no | glycogen converted to glucose |
| D | no | yes | glucose converted to glycogen |
Which row describes the body’s response to a decrease in blood sugar levels?
[1]
Which term describes the ability to see two points as separate points and not merged into one?
A Depth of field
B Magnification
C Power
D Resolution
[1]
Stem cells are found in both animals and plants.
Fig. 11.1 shows the area where stem cells can be found in a plant.
What is the name of the area where stem cells are found?
[1]
Describe the difference between embryonic and adult stem cells in animals.
[1]
A group of people were asked if they were in favour of using embryonic stem cells for medical research.
The pie chart in Fig. 11.2 shows the results.
There were 254 people in the survey.
Calculate the total number of people who were against the use of embryonic stem cells.
Give your answer to the nearest whole number.
[3]
Suggest two reasons why some people may object to the use of embryonic stem cells.
[2]
Hormones are used for coordination within the human body.
Complete these sentences about hormones.
Hormones are chemical........
Hormones are made in........ glands.
[2]
The diagram shows how the levels of the hormones oestrogen and progesterone change during the menstrual cycle.
Describe how changes in the levels of these hormones affect the thickness of the uterus wall.
Use data from the graph in your answer.
[2]
What is the role of FSH in the menstrual cycle?
[1]
Fig. 13.1 shows a red blood cell.
Explain one way red blood cells are adapted to transport oxygen around the body.
[2]
Which gas diffuses out of blood and into the lungs?
[1]
Fig. 13.2 shows two different blood vessels, X and Y, that are connected to the heart.
Which blood vessel, X or Y, is most likely to be the vena cava?
Use Fig. 13.2 to explain your answer.
[2]
Why was each pot covered with a clear plastic bag?
[1]
What would be the effect on the results if the pots were not covered?
[1]
The student has not tried to reduce the effects of random error.
Suggest how they should have done this.
[1]
Write down the independent variable and dependent variable for this investigation.
Independent variable........
Dependent variable........
[2]
Plant C has 2 leaves. It had a starting mass of 138 g. After 24 hours the mass of plant C was 131 g.
Calculate the percentage decrease in mass for plant C.
Give your answer to 2 significant figures.
[3]
* The percentage decrease in mass for:
• plant A (6 leaves) is 16.2%
• plant B (4 leaves) is 8.9%.
Explain the difference in the percentage decrease for plant A and plant B.
Use ideas about transpiration in your answer.
[6]
Explain why the student leaves the test tubes in the water bath for 5 minutes before mixing them.
[1]
The table shows the student’s results.
| Temperature of water bath (°C) | Time when indicator stays orange (seconds) |
| 20 | 568 |
| 30 | 360 |
| 40 | 60 |
| 50 | 340 |
| 60 | Indicator still changes colour after 600 |
Explain why amylase works slowly at 50 °C but no longer works at 60 °C.
[2]
The student has investigated the effect of temperature on the activity of amylase.
Describe how they could develop their investigation to find the effect of pH on the activity of amylase.
[4]
Fig. 16.1 shows a single-celled organism called an alga.
The alga cell is a eukaryotic cell.
Describe two differences in structure between eukaryotic and prokaryotic cells.
[2]
Explain why chloroplasts are needed for photosynthesis.
[1]
Fig. 16.2 shows algae growing on the surface of a lake.
In the summer the area covered by the algae increases.
Other plants growing at the bottom of the lake receive less light.
Explain how this could affect the growth of the plants at the bottom of the lake.
[2]
Compare the process of photosynthesis with the process of aerobic respiration.
[3]
The paper as printed
Spotted a mistake on this page?Report a problem
