1.
State what is meant by ultrastructure of a eukaryotic cell.
[1 mark]
- organelles with specific functions
JD SCIENCE
Cells
Indicative marking points. Award marks for equivalent scientific or mathematical wording. Do not issue this sheet with the student worksheet.
2.
State what is meant by a prokaryotic cell.
[1 mark]
- no nucleus, 70S ribosomes, cell wall of murein
3.
State what is meant by the magnification formula.
[1 mark]
- magnification = image / actual
4.
State what is meant by an organelle.
[1 mark]
- specialised structure in a cell
5.
State what is meant by the fluid mosaic model.
[1 mark]
- phospholipid bilayer with proteins
6.
State what is meant by osmosis in terms of water potential.
[1 mark]
- water moves from high to low ψ
7.
State what is meant by active transport.
[1 mark]
- against a gradient using ATP and carrier proteins
8.
State what is meant by mitosis.
[1 mark]
- produces two genetically identical cells
9.
State what is meant by the cell cycle.
[1 mark]
- interphase + mitosis + cytokinesis
10.
State what is meant by an antibody.
[1 mark]
- protein produced by plasma cells
11.
Amira is asked about ultrastructure of a eukaryotic cell in a AQA Biology paper.
(a) [2 marks]
- nucleus, mitochondria, RER, Golgi, lysosomes
(b) [3 marks]
- division of labour
12.
Amira is asked about a prokaryotic cell in a AQA Biology paper.
(a) [2 marks]
- plasmids, flagella, capsule
(b) [3 marks]
- smaller than eukaryotes
13.
Amira is asked about the magnification formula in a AQA Biology paper.
(a) [2 marks]
- convert units first
(b) [3 marks]
- µm and nm
14.
Amira is asked about an organelle in a AQA Biology paper.
(a) [2 marks]
- mitochondrion: aerobic respiration
(b) [3 marks]
- chloroplast: photosynthesis
15.
Amira is asked about the fluid mosaic model in a AQA Biology paper.
(a) [2 marks]
- fluid: phospholipids move; mosaic: proteins
(b) [3 marks]
- partially permeable
16.
Amira is asked about osmosis in terms of water potential in a AQA Biology paper.
(a) [2 marks]
- ψ of pure water is 0
(b) [3 marks]
- solutes lower ψ
17.
Image 40 mm, actual 8 µm. Magnification
[3 marks]
- Final answer: ×5000
18.
Scale bar 2 cm represents 5 µm. Magnification
[3 marks]
- Final answer: ×4000
19.
A cell is 20 µm. Length in mm
[3 marks]
- Final answer: 0.020 mm
20.
Water potential: cell −400 kPa, solution −800 kPa. Direction of water
[3 marks]
- Final answer: out of the cell
21.
Mitotic index: 18 cells in mitosis out of 200
[3 marks]
- Final answer: 0.09
22.
A bacterium 2 µm long at ×10 000. Image size
[3 marks]
- Final answer: 20 mm
23.
Amira carries out a AQA-style required practical linked to cells and microscopy. This is a typical AQA required-practical style question.
(a) [2 marks]
- Independent: the independent variable for this topic
- Dependent: the measured outcome
(b) [2 marks]
- keep all other variables constant
- so the test is fair / only one variable is changed
(c) [2 marks]
- repeat and calculate a mean / use a tighter method
24.
Amira carries out collecting valid data for cells and microscopy. This is a typical AQA required-practical style question.
(a) [2 marks]
- Independent: a chosen factor
- Dependent: a quantitative measurement
(b) [2 marks]
- calibrated instrument
- so the test is fair / only one variable is changed
(c) [2 marks]
- systematic error from zero error
25.
Amira carries out drawing a graph for cells and microscopy. This is a typical AQA required-practical style question.
(a) [2 marks]
- Independent: x-variable
- Dependent: y-variable
(b) [2 marks]
- same scale / same apparatus
- so the test is fair / only one variable is changed
(c) [2 marks]
- not drawing a line of best fit through the trend
26.
Amira carries out evaluating a method about cells and microscopy. This is a typical AQA required-practical style question.
(a) [2 marks]
- Independent: method change
- Dependent: precision / accuracy
(b) [2 marks]
- same sample size
- so the test is fair / only one variable is changed
(c) [2 marks]
- too few repeats
27.
Compare ultrastructure of a eukaryotic cell with a prokaryotic cell.
[4 marks]
- organelles with specific functions
- no nucleus, 70S ribosomes, cell wall of murein
- give one linked difference
28.
Compare a prokaryotic cell with the magnification formula.
[4 marks]
- no nucleus, 70S ribosomes, cell wall of murein
- magnification = image / actual
- give one linked difference
29.
Compare the magnification formula with an organelle.
[4 marks]
- magnification = image / actual
- specialised structure in a cell
- give one linked difference
30.
Compare an organelle with the fluid mosaic model.
[4 marks]
- specialised structure in a cell
- phospholipid bilayer with proteins
- give one linked difference
31.
Apply your knowledge of active transport to this situation: e.g. mineral ions in roots
[3 marks]
- e.g. mineral ions in roots
32.
Apply your knowledge of mitosis to this situation: prophase metaphase anaphase telophase
[3 marks]
- prophase metaphase anaphase telophase