AQA GCSE Biology Higher Tier
TOPIC ONE: CELL BIOLOGY: TOPIC ONE: CELL BIOLOGY
1. Eukaryotes: Plants, Animals, Fungi, Protists
DNA in nucleus
2. Prokaryotes: Bacteria
Loose DNA or DNA in plasmid (Ring of DNA)
3. Chloroplast: Site of photosynthesis
4. Mitochondria: Where energy is released during aerobic respiration
5. Cell membrane: Controls what enters and exits the cell
6. Ribosomes: Where protein synthesis occurs
7. Nucleus: Controls cell's activities and contains DNA
8. Cytoplasm: Where chemical reactions take place
9. Permanent vacuole: Contains cell sap to help keep the cell turgid
10. Cell wall: Provides support and gives cell its shape
11. Sperm Cell Adaptations: Have flagellum to swim to ovum
Have many mitochondria to provide energy for swimming
Enzymes in head to digest outer layer of ovum
12. Nerve Cell Adaptations: Axon - Carries electrical impulses around body
Myelin - Insulates axon & speeds up nerve impulses
Dendrites - Increase surface area so other nerve cells can connect easily
End of axon has synapses so impulses can pass from one cell to another
13. Muscle Cell Adaptations: Have many mitochondria to provide energy for contracting
14. Root Hair Cell Adaptations: Hairs increase surface area to absorb water + minerals faster
Do not have chloroplasts as underground
Lots of mitochondria for energy for active transport
15. Xylem Cell Adaptations: Transpiration Stream
Transports unidirectionally
Transports Water + Minerals (Magnesium used to make chlorophyll)
,Thick walls for structure
Made of dead cells
, 16. Phloem Cell Adaptations: Translocation
Transports bidirectionally
Transports dissolved sugars
17. Microscopes Required Practical: 1. Place slide on stage and use clips to hold in place
2. Select lowest power objective lens
3. Turn coarse focusing dial until it almost touches the slide
4. Look through eyepiece and turn coarse focusing dial until cells come into focus
5. Then use fine focusing dial to clearly focus cells
6. Total magnification = Mag of Eyepiece x Mag of Objective lens
7. Draw image in microscope on paper, including magnification scale
18. Light Microscopes: Limited Magnification
Limited Resolution
Less Expensive
19. Electron Microscopes: Greater Magnification
Greater Resolution
More expensive
20. Bacterial Division - Binary Fission: 1 = No. Rounds of Division
2 = Do 2^No. Rounds of Division
3 = Convert to Standard Form
21. Mitosis: 1. DNA replicates to form 2 copies of each chromosome
2. Cell grows and copies all sub-cellular structures
3. Sets of chromosomes pulled to each end of cell by fibres
4. Nucleus divides and then cytoplasm and cell membrane divides to form 2 identical cells
22. Diffusion: The net movement of particles from an area of high concentration to an area of low concentration
23. Factors affecting diffusion: Higher temp = Increased rate of dittusion as particles have more kinetic
energy
Increased surface area = Increased rate of dittusion
24. Osmosis: The net movement of water molecules from a dilute to a concentrated solution through a semi
permeable membrane
25. Active Transport: Moves substances from a more dilute solution to a more concentrated solution - Requires
energy from respiration
TOPIC ONE: CELL BIOLOGY: TOPIC ONE: CELL BIOLOGY
1. Eukaryotes: Plants, Animals, Fungi, Protists
DNA in nucleus
2. Prokaryotes: Bacteria
Loose DNA or DNA in plasmid (Ring of DNA)
3. Chloroplast: Site of photosynthesis
4. Mitochondria: Where energy is released during aerobic respiration
5. Cell membrane: Controls what enters and exits the cell
6. Ribosomes: Where protein synthesis occurs
7. Nucleus: Controls cell's activities and contains DNA
8. Cytoplasm: Where chemical reactions take place
9. Permanent vacuole: Contains cell sap to help keep the cell turgid
10. Cell wall: Provides support and gives cell its shape
11. Sperm Cell Adaptations: Have flagellum to swim to ovum
Have many mitochondria to provide energy for swimming
Enzymes in head to digest outer layer of ovum
12. Nerve Cell Adaptations: Axon - Carries electrical impulses around body
Myelin - Insulates axon & speeds up nerve impulses
Dendrites - Increase surface area so other nerve cells can connect easily
End of axon has synapses so impulses can pass from one cell to another
13. Muscle Cell Adaptations: Have many mitochondria to provide energy for contracting
14. Root Hair Cell Adaptations: Hairs increase surface area to absorb water + minerals faster
Do not have chloroplasts as underground
Lots of mitochondria for energy for active transport
15. Xylem Cell Adaptations: Transpiration Stream
Transports unidirectionally
Transports Water + Minerals (Magnesium used to make chlorophyll)
,Thick walls for structure
Made of dead cells
, 16. Phloem Cell Adaptations: Translocation
Transports bidirectionally
Transports dissolved sugars
17. Microscopes Required Practical: 1. Place slide on stage and use clips to hold in place
2. Select lowest power objective lens
3. Turn coarse focusing dial until it almost touches the slide
4. Look through eyepiece and turn coarse focusing dial until cells come into focus
5. Then use fine focusing dial to clearly focus cells
6. Total magnification = Mag of Eyepiece x Mag of Objective lens
7. Draw image in microscope on paper, including magnification scale
18. Light Microscopes: Limited Magnification
Limited Resolution
Less Expensive
19. Electron Microscopes: Greater Magnification
Greater Resolution
More expensive
20. Bacterial Division - Binary Fission: 1 = No. Rounds of Division
2 = Do 2^No. Rounds of Division
3 = Convert to Standard Form
21. Mitosis: 1. DNA replicates to form 2 copies of each chromosome
2. Cell grows and copies all sub-cellular structures
3. Sets of chromosomes pulled to each end of cell by fibres
4. Nucleus divides and then cytoplasm and cell membrane divides to form 2 identical cells
22. Diffusion: The net movement of particles from an area of high concentration to an area of low concentration
23. Factors affecting diffusion: Higher temp = Increased rate of dittusion as particles have more kinetic
energy
Increased surface area = Increased rate of dittusion
24. Osmosis: The net movement of water molecules from a dilute to a concentrated solution through a semi
permeable membrane
25. Active Transport: Moves substances from a more dilute solution to a more concentrated solution - Requires
energy from respiration
