1 markWhen preparing a slide of cells to examine down a light microscope, which is the best reason for needing to achieve a sample that is just one cell thick?
To ensure a 2-dimensional view of the cell is achieved
So fewer cells are visible in the field of view but in more detail
To reduce the chance of bubbles forming under the coverslip
To be thin enough to allow light to transmit through the sample
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1 markWhich of the tables (A - D) gives the correct food tests for all four major food groups?
| Glucose (a reducing sugar) | Lipids | Proteins | Starch |
Benedict's test | X |
|
|
|
Biuret test |
|
| X |
|
Ethanol test |
| X |
|
|
Iodine test |
|
|
| X |
| Glucose (a reducing sugar) | Lipids | Proteins | Starch |
Benedict's test |
| X |
|
|
Biuret test |
|
| X |
|
Ethanol test | X |
|
|
|
Iodine test |
|
|
| X |
| Glucose (a reducing sugar) | Lipids | Proteins | Starch |
Benedict's test | X |
|
|
|
Biuret test |
| X |
|
|
Ethanol test |
|
|
| X |
Iodine test |
|
| X |
|
| Glucose (a reducing sugar) | Lipids | Proteins | Starch |
Benedict's test |
|
| X |
|
Biuret test |
| X |
|
|
Ethanol test | X |
|
|
|
Iodine test |
|
|
| X |
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1 markWhen calculating the rate of an enzyme-controlled reaction as part of an experiment into factors that affect the rate, which of the following would be the most unsuitable unit of measurement of the rate?
mg cm-3 min-1
mmol ml s-1
g dm-3 s-1
g cm-3 mmol-1
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1 markWhen carrying out work with microorganisms in a school laboratory, which of the following is not an aspect of aseptic technique that should be followed by students?
Disinfecting work surfaces before and after an experiment
Working in a dust-free atmosphere with filtered air to reduce contamination
Working in the area immediately surrounding a lit Bunsen burner
Flaming the necks of bottles used to contain microorganisms to prevent contamination
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1 markWhat is the surface area : volume ratio of a cube that has a side length of 3cm?
0.5
1
2
6
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1 markA student uses a microscope to look at plant cells on a slide.
Which of these methods should they use first?
Highest power objective lens and focus moving the lens away from the slide
Highest power objective lens and focus moving the lens towards the slide
Lowest power objective lens and focus moving the lens away from the slide
Lowest power objective lens and focus moving the lens towards the slide
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1 markThe diagram shows positive results in two different food tests.
What do the results show in each tube?
| Tube 1 | Tube 2 |
A | sugar | lipid |
B | starch | sugar |
C | protein | sugar |
D | starch | protein |
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1 markThe pictures show four foxes.
Which fox has the largest surface area : volume ratio?
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1 markA student uses a microscope.
The magnification on the eyepiece lens is ×10.
The magnification on the objective lens is ×4.
What is the total magnification?
2.5
6
14
40
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1 markWhich substance gives a positive test with Benedict’s reagent?
Lipid
Protein
Starch
Sugar
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1 markA student places an antibiotic disc onto the surface of agar that is covered in bacteria.
She calculates the area around the disc that is free from bacteria.
Which formula should she use?
2πb2 – 2πa2
πb2 + πa2
πb2 – πa2
π(b – a)2
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1 markThe diagram shows a variegated leaf.
Which diagram shows the correct starch test results for the variegated leaf?
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1 markA student wants to test for protein.
What would they use to test for protein?
Benedict’s reagent
Biuret reagent
Iodine solution
Ethanol
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1 markA scientist is estimating the number of rabbits in a field.
He has eight different estimates, 12, 12, 13, 15, 17, 19, 22 and 26.
Which is the median value for his estimates?
8
12
16
17
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1 markA group of students collected some measurements from a field.
They plotted the measurements on this graph.
Which technique have the students used to collect the data?
Capture-recapture
Random quadrats
Scaling up
Transect line with quadrats
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1 markA student uses a simple potometer to study the effect of different temperatures on the cut shoot of a plant.
What does the potometer actually measure?
Volume of water evaporating from the leaves of the shoot
Volume of water produced by respiration in the shoot
Volume of water taken up by the shoot
Volume of water used in photosynthesis in the shoot
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1 markA plant cell is placed in a solution with a higher solute concentration than the cell contents.
What will happen to the plant cell?
Absorb water until it bursts.
Absorb water until it is turgid.
Lose cytoplasm and shrink.
Lose water and become flaccid.
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