One to four mark questions
One to four mark questions will start with command words such as 'describe' or 'explain'. Some command words are easy to understand such as:
- 'calculate' or 'determine' for maths questions
- 'complete' to fill in a gap in a table or graph
- 'define' to give the meaning of an important word
- 'suggest' where you use your knowledge in an unfamiliar situation
- 'compare' where you describe the similarities and/or differences between things
The command words 'describe' and 'explain' can be confusing. If you are asked to describe a graph, you will be expected to write about its overall shape, whether it is linear or curved, the slope of gradients etc. If you are asked to explain why a pattern or trend is seen in a graph, you will be expected to use your science knowledge, not just say what you see (which is a description), eg the graph shows a steep linear increase for the first three hours because…
Explain how and why questions often have the word 'because' in their answer. Describe questions don't.
The number of marks per question part is given in this form '[2 marks]'. It is essential that you give two different answers if a question is worth two marks. Sometimes you can gain a second mark by giving the units in a calculation or stating specific data points, eg during the first two years the number of lions decreased by seven.
You will be expected to write in more depth for three and four mark questions. They might ask you about a process such as the carbon cycle or the method you would use in an experiment.
These questions have been written by Bitesize consultants as suggestions to the types of questions that may appear in an exam paper.
Sample question 1 - Foundation
Question
Select the two incorrect statements. [2 marks]
| A | Embryonic stem cells are only found in specific locations like the nose and bone marrow |
| B | An embryo is made from embryonic stem cells |
| C | Adult stem cells can differentiate into all cell types |
| D | Embryonic stem cells can differentiate into all cell types |
| A |
| Embryonic stem cells are only found in specific locations like the nose and bone marrow |
| B |
| An embryo is made from embryonic stem cells |
| C |
| Adult stem cells can differentiate into all cell types |
| D |
| Embryonic stem cells can differentiate into all cell types |
A and C
Sample question 2 - Foundation
Question
Name the type of cell in plants that can differentiate into different types of cell. [1 mark]
Meristem cell or meristematic cell.
Note that you must be specific. It isn't sufficient to call it a 'stem cell', as stem cells occur in animals.
Sample question 3 - Foundation
Question
Describe how a sperm cell is adapted to its role. [4 marks]
Four from:
- Role is to fertilise an egg.
- The head has the nucleus, which contains the male genetic material.
- It has a tail for swimming.
- The acrosome has enzymes so that the sperm can penetrate the egg.
- It is packed with mitochondria to supply the energy for movement.
Sample question 4 - Higher
Question
State how a potometer can be used for measuring transpiration. What is the main limitation? [2 marks]
It measures the rate of water uptake by a plant shoot which gives an indication of the rate of transpiration.
Water uptake by a plant is often very similar to the rate of transpiration, but not always because water is used for other purposes such as photosynthesis, or for making cells turgid.
Sample question 5 - Higher
Question
In an osmosis experiment, after 45 minutes a potato cylinder had lost 2.4 g in mass.
Calculate the rate of water loss from the potato cylinder in grams per hour. [2 marks]
3.2 g/h
45 minutes = 0.75 h
The water lost in 0.75 h is 2.4 g
Therefore, \(\frac{2.4}{0.75}\) g of water would be lost in 1 hour
The rate of water loss is 3.2 g per hour, or written more scientifically, 3.2 g/h.
Note that rate is a compound measure and always has more than one unit.
Sample question 6 - Higher
Question
Explain how plant roots are adapted for osmosis and active transport and give an example of a substance absorbed by each process. [4 marks]
Four from:
- Osmosis is the net movement of molecules from an area of high to lower concentration of water across a partially permeable membrane. This could also be described as moving from a dilute solution to a more concentrated one, or from high water potential to low water potential.
- Active transport is the net movement of molecules from an area of low to high concentration and requires energy.
- Plants use active transport to absorb mineral ions which are in low concentrations in the soil and higher concentrations in the plant.
- Plants have root hair cells.
- These increase the surface area of the plant in contact with the soil.
- This allows greater osmosis and active transport.