Which is the correct order of size from smallest to largest?
10 mm, 30 µm, 2000 nm.
900 nm, 4 µm, 0.4 mm.
40 nm, 1.4 mm, 4 µm.
300 nm, 3 µm, 0.003 mm.
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Which is the correct order of size from smallest to largest?
10 mm, 30 µm, 2000 nm.
900 nm, 4 µm, 0.4 mm.
40 nm, 1.4 mm, 4 µm.
300 nm, 3 µm, 0.003 mm.
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Why is it not possible to visualise cell membranes under a light microscope but chloroplasts can be easily seen?
There is no suitable staining method for cell membranes.
Chloroplasts are abundant in many plant cells.
Chloroplasts are green in colour so can be easily visualised.
Light microscopes do not have sufficient magnification / resolution to visualise the cell membrane.
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Which of the following is a defining feature of prokaryotic cells compared to eukaryotic plant cells?
Circular chromosomal DNA present in the cytoplasm.
Mitochondria are present.
Circular plasmid DNA may be present in the nucleus.
They lack a cell wall.
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Which of the following statements about plant cell and animal cells is incorrect?
Plant cells | Animal cells | |
A | Have a cell wall | Lack a cell wall |
B | Contain mitochondria | Contain mitochondria |
C | Contain chloroplasts | Lack chloroplasts |
D | Lack a cell membrane | Have a cell membrane |
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Which of the following statements about electron microscopy is incorrect?
Electron microscopes have improved our understanding of the cell.
Only dead specimens can be visualised.
Electron beams have a longer wavelength than visible light.
Higher resolution and magnification can be attained compared to light microscopy.
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The diameter of a human egg cell is 120 μm.
What is the diameter in mm?
1.2 × 10–1
1.2 × 10–2
1.2 × 10–3
1.2 × 10–4
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Which of these structures is found in eukaryotic but not prokaryotic cells?
Cell wall
Cytoplasm
Nucleus
Plasmid
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A 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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The microscope used by the student has an eyepiece lens with a magnification of 10×.
Which objective lens would give an image magnification of 200×?
10×
20×
30×
200×
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Look at the bacterial cell that causes disease in humans.
The human eye can see objects 0.1mm in size.
What minimum magnification will be needed before the eye can see this bacterial cell?
12.5×
125×
1250×
12500×
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The resolution of an electron microscope is 0.1 nanometres.
The resolution of the eye is 100 micrometres.
How many times greater is the resolution of the electron microscope than the eye?
(1 micrometre = 1000 nanometres)
1000
10000
100000
1000000
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The diagram shows a light microscope.
Which label is pointing to the eyepiece lens?
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A light microscope resolution is 0.2μm. An electron microscope resolution is 0.0001μm.
How many times closer can two objects be seen as separate objects by using an electron microscope compared to using a light microscope?
2x
20x
200x
2000x
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A cell structure measures 1 micrometre in diameter.
What is the diameter of the cell structure in metres?
1 × 10–3 metres
1 × 10–6 metres
1 × 10–9 metres
1 × 10–12 metres
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A human cell has 10000 mitochondria and a yeast cell has 10.
By how many orders of magnitude are there more mitochondria in a human cell than in a yeast cell?
2
3
10
1000
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The diagram shows a plant cell observed using a light microscope.
Which label is pointing to a structure that contains genetic material?
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