5/6/26, 6:44 Edexcel gcse combined sci
AM
AQA GCSE Combined Science Biology Paper 1 (8464) –
Full Revision Notes on Cells, Enzymes, Organisation,
Infection & Bioenergetics.
What is the function of the nucleus?
Contains DNA to control the cell
What is the function of the cell membrane?
Controls entry and exit of substances
What is the function of the cell wall?
Provides structure and support
What is the function of mitochondria?
Carry out respiration to release energy
What is the function of ribosomes?
Protein synthesis
What is the function of chloroplasts?
Carry out photosynthesis
What is the function of a vacuole?
Contains cell sap
Define a prokaryote
A cell that does not have a nucleus
Define a eukaryote
A cell that has DNA in a nucleus
Name two cell structures that are in a eukaryote but not in a prokaryote
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,5/6/26, 6:44 Edexcel gcse combined sci
AM
Nucleus, mitochondria, chloroplasts
2/29
, 5/6/26, 6:44 Edexcel gcse combined sci
AM
What is a plasmid?
A small loop of DNA in bacteria
What is a plant cell wall made from?
Cellulose
How is DNA stored in a bacterial cell?
As a single, free-floating loop; also on plasmids
What is differentiation?
The process by which cells become specialised
What is the equation for magnification?
Magnification = Image Size ÷ Actual Size
A photograph of a cell is 15mm long. It has a magnification of 1100x. What is the
actual size?
0.0136mm, or 13.6µm
A cell is 12µm wide. It is magnified by 450 times. How big is the image?
5400µm, or 5.4mm
If the image of a virus is 1.2mm, and its actual size is 0.2µm, how much has it been
magnified by?
6000 times
Convert 38500µm into mm
38.5mm
How many µm are in 1mm?
1000
Write 17400m in standard form
3/29
AM
AQA GCSE Combined Science Biology Paper 1 (8464) –
Full Revision Notes on Cells, Enzymes, Organisation,
Infection & Bioenergetics.
What is the function of the nucleus?
Contains DNA to control the cell
What is the function of the cell membrane?
Controls entry and exit of substances
What is the function of the cell wall?
Provides structure and support
What is the function of mitochondria?
Carry out respiration to release energy
What is the function of ribosomes?
Protein synthesis
What is the function of chloroplasts?
Carry out photosynthesis
What is the function of a vacuole?
Contains cell sap
Define a prokaryote
A cell that does not have a nucleus
Define a eukaryote
A cell that has DNA in a nucleus
Name two cell structures that are in a eukaryote but not in a prokaryote
1/29
,5/6/26, 6:44 Edexcel gcse combined sci
AM
Nucleus, mitochondria, chloroplasts
2/29
, 5/6/26, 6:44 Edexcel gcse combined sci
AM
What is a plasmid?
A small loop of DNA in bacteria
What is a plant cell wall made from?
Cellulose
How is DNA stored in a bacterial cell?
As a single, free-floating loop; also on plasmids
What is differentiation?
The process by which cells become specialised
What is the equation for magnification?
Magnification = Image Size ÷ Actual Size
A photograph of a cell is 15mm long. It has a magnification of 1100x. What is the
actual size?
0.0136mm, or 13.6µm
A cell is 12µm wide. It is magnified by 450 times. How big is the image?
5400µm, or 5.4mm
If the image of a virus is 1.2mm, and its actual size is 0.2µm, how much has it been
magnified by?
6000 times
Convert 38500µm into mm
38.5mm
How many µm are in 1mm?
1000
Write 17400m in standard form
3/29
