Biology aqa A level common questions, AQA A Level Biology Topic 5 Exa
Questions, biology paper 2 aqa a level
Study online at https://quizlet.com/_hegan6
1. give two factors other than age and gender that would affect the concentra-
tion of creatinine in the blood ?: muscle/ body mass
ethnicity
2. Explain how the cells of the collecting duct are able to absorb water from the
filtrate through the protein channels in their plasma membranes?: lower w.p/ more
negative inside tubule cells so h2o enters by osmosis
3. Suggest why diabetes insipidus is more common in males ?: Bc males only have X
chromosome do not have Y chromosome single copy of recessive allele will be expressed
4. A recessive allele which has harmful effects is able to reach a higher frequency
in a population than a harmful dominant allele. Explain how ?: recessive allele can be
carried by individuals showing ettects dominant allel always expressed
organisms that are attected are more likely to reproduce therefore recessive alleles are more likely to be passed on
5. In some forms of kidney disease, proteins from the blood plasma are found in
the urine. Which part of the nephron would have been damaged by the disease
to cause proteins from blood plasma to be present in the urine? Explain your
answer: glomerulus/ bowmans capsule
basement membrane
proteins are large molecules cannot normally pass through filter
can only pass through if filter damaged
6. Describe the role of the hormone glucagon in the control of blood sugar
concentration ?: glucagon binds to specific receptor on liver cells
activation of enzymes in liver
hydrolysis of glycogen
F.D of glucose out of liver cells
increases blood glucose levels
7. Explain two ways in which the cells of the proximal convoluted tubule are
adapted for reabsorption.?: microvilli provide a large S.A for reabsorption
carrier protiens in membrane for A.T
channel proteins for F.D
many mitochondria for A.T and providing Atp
, Biology aqa A level common questions, AQA A Level Biology Topic 5 Exa
Questions, biology paper 2 aqa a level
Study online at https://quizlet.com/_hegan6
8. Explain the role of the loop of Henle in the absorption of water from the
flitrate ?: in the ascending limb na+ ions actively transported
ascending limb impermeable to water
in descending limb na+ ions dittuse in
descending limb h2o moves out
low w.p ( high conc of ions in medulla) the longer the loop, lower w.p in medulla
h2o leaves collecting duct by osmosis down w.p gradient
9. Explain the role of ADH in the production of concentrated urine?: when w.p of blood
too low it is detected by receptors in hypothalamus
pituitary secretes releases more ADH
ADH increases permeability opens channels for h2o in DCT
more h2o reabsorbed into blood by osmosis down w.p gradient
10. Explain how different subspecies of giraffe may have evolved from a com-
mon ancestor ? (5): 1) no interbreeding/geographical isolation
2) variation due to mutation linked to ditterent markings (colours)
3) survival linked to ditterent markings ditterent selection pressure
4) adapted organisms survive and reproduce ( ditterent reproductive success)
5) increase in allele frequencies
11. describe how crop plants use light energy during the light dependent reac-
tion? (5): 1) excites electrons
2) electrons move along electron transfer chain releasing energy
3) energy used to join ADP + Pi -> ATP
4) photolysis of H2O produces P, e- and O2
5) NADP reduced by hydrogen
12. describe how altered DNA may lead to cancer ? (6): 1. (DNA altered by) mutation;
2. (mutation) changes base sequence;
3. Of gene controlling cell growth / oncogene / that monitors cell division;
4. Of tumour suppressor gene;
5. Change protein structure / non-functional protein / protein not formed;
6. (Tumour suppressor genes) produce proteins that inhibit cell division;
7. Mitosis;
, Biology aqa A level common questions, AQA A Level Biology Topic 5 Exa
Questions, biology paper 2 aqa a level
Study online at https://quizlet.com/_hegan6
8. Uncontrolled / rapid / abnormal (cell division);
9. Malignant tumour;
13. why would one area ( e.g wild ower meadow) have a higher species diversity
than another e.g potato field ? (5): 1) there would be more plant species
2) hence more habitats
3) more niches
4) more food sources
5) the area is able to support more biomass
14. describe competitive and non-competitive inhibition of enzyme ? (6): competitive
inhibitor
1) inhibitors reduce binding of enzyme to substrate/prevent formation of e-s complexes
2) inhibitor similar shape to substrate binds to active site of enzyme
3) inhibition can be overcome by adding more substrate
non-competitive inhibitor
4) inhibitor binds to site on enzyme other than active site
5) prevents formation of active site/ changes shape of active site
6) cannot be overcome by adding more substrate
15. Meiosis: cell ÷ to form gametes
2 ÷ forming 4 haploid daughter cells
genetically non-identical due to crossing over and independent segregation (assortment)
crossing over- creates new combination of alleles
independent assortment - creates new combination of chromosomes
16. Mitosis: cell divides for growth and repair
2 genetically identical daughter cells
prophase - nuclear membrane breaks down and chromosomes condense
metaphase- chromosomes line up on the equator and spindle fibres attach to chromosome at the centromere
anaphase - centromeres split and chromatids move to opposite poles
, Biology aqa A level common questions, AQA A Level Biology Topic 5 Exa
Questions, biology paper 2 aqa a level
Study online at https://quizlet.com/_hegan6
telophase - nuclear membrane reforms, chromosomes uncoil and cell ÷by cytokinesis
interphase - cells grow and organelles multiply and dna replicates, organelles multiply ready to ÷
17. heart disease ? (6): atheroma is cholesterol
in artery wall
atheroma is linked to blood clot
blocks coronary artery ( artery supplying heart muscle/tissue/ cells)
reduces o2 supply to heart muscle/ tissues/cells
unable to respire so die
18. Meiosis: prophase 1 - nuclear membrane breaks down, chromosomes condense
metaphase 1 - homologous pair of chromosomes line up next to each other on the equator, spindle attaches to
chromosome at the centromere, crossing over chromatid takes place
anaphase 1 - homologous pairs seperate 1 to each pole ( independent assortment )
telophase 1 - nuclear membrane reforms, cell ÷ by cytokinesis
prophase 2 - nuclear membrane breaks down, chromosomes condense
metaphase 2- chromosomes line up on the equator and spindle attaches to chromosome at the centromere
anaphase 2 - centromere split, chromatids move to opposite poles
telophase 2- nuclear membrane reforms, chromosomes uncoil, cell ÷ by cytokinesis
19. natural selection? (6): 1) variation of phenotypes in population due to random mutations
2) individuals that do not show behaviour die
3) change in selection pressue- environmental change
4) allele frequency increases in population
5) those who have the advantageous alleles, survive and reproduce and pass on their alleles giving a selective advantage
to their ottspring
6) until all individuals show the phenotype frequency of alleles in the population changes
20. tissue fluid? (6): high b.p/h.p
forces h2o out
large proteins remain in capillary
low w.p in capillary
due to plasma proteins
h2o enters capillary by osmosis
Questions, biology paper 2 aqa a level
Study online at https://quizlet.com/_hegan6
1. give two factors other than age and gender that would affect the concentra-
tion of creatinine in the blood ?: muscle/ body mass
ethnicity
2. Explain how the cells of the collecting duct are able to absorb water from the
filtrate through the protein channels in their plasma membranes?: lower w.p/ more
negative inside tubule cells so h2o enters by osmosis
3. Suggest why diabetes insipidus is more common in males ?: Bc males only have X
chromosome do not have Y chromosome single copy of recessive allele will be expressed
4. A recessive allele which has harmful effects is able to reach a higher frequency
in a population than a harmful dominant allele. Explain how ?: recessive allele can be
carried by individuals showing ettects dominant allel always expressed
organisms that are attected are more likely to reproduce therefore recessive alleles are more likely to be passed on
5. In some forms of kidney disease, proteins from the blood plasma are found in
the urine. Which part of the nephron would have been damaged by the disease
to cause proteins from blood plasma to be present in the urine? Explain your
answer: glomerulus/ bowmans capsule
basement membrane
proteins are large molecules cannot normally pass through filter
can only pass through if filter damaged
6. Describe the role of the hormone glucagon in the control of blood sugar
concentration ?: glucagon binds to specific receptor on liver cells
activation of enzymes in liver
hydrolysis of glycogen
F.D of glucose out of liver cells
increases blood glucose levels
7. Explain two ways in which the cells of the proximal convoluted tubule are
adapted for reabsorption.?: microvilli provide a large S.A for reabsorption
carrier protiens in membrane for A.T
channel proteins for F.D
many mitochondria for A.T and providing Atp
, Biology aqa A level common questions, AQA A Level Biology Topic 5 Exa
Questions, biology paper 2 aqa a level
Study online at https://quizlet.com/_hegan6
8. Explain the role of the loop of Henle in the absorption of water from the
flitrate ?: in the ascending limb na+ ions actively transported
ascending limb impermeable to water
in descending limb na+ ions dittuse in
descending limb h2o moves out
low w.p ( high conc of ions in medulla) the longer the loop, lower w.p in medulla
h2o leaves collecting duct by osmosis down w.p gradient
9. Explain the role of ADH in the production of concentrated urine?: when w.p of blood
too low it is detected by receptors in hypothalamus
pituitary secretes releases more ADH
ADH increases permeability opens channels for h2o in DCT
more h2o reabsorbed into blood by osmosis down w.p gradient
10. Explain how different subspecies of giraffe may have evolved from a com-
mon ancestor ? (5): 1) no interbreeding/geographical isolation
2) variation due to mutation linked to ditterent markings (colours)
3) survival linked to ditterent markings ditterent selection pressure
4) adapted organisms survive and reproduce ( ditterent reproductive success)
5) increase in allele frequencies
11. describe how crop plants use light energy during the light dependent reac-
tion? (5): 1) excites electrons
2) electrons move along electron transfer chain releasing energy
3) energy used to join ADP + Pi -> ATP
4) photolysis of H2O produces P, e- and O2
5) NADP reduced by hydrogen
12. describe how altered DNA may lead to cancer ? (6): 1. (DNA altered by) mutation;
2. (mutation) changes base sequence;
3. Of gene controlling cell growth / oncogene / that monitors cell division;
4. Of tumour suppressor gene;
5. Change protein structure / non-functional protein / protein not formed;
6. (Tumour suppressor genes) produce proteins that inhibit cell division;
7. Mitosis;
, Biology aqa A level common questions, AQA A Level Biology Topic 5 Exa
Questions, biology paper 2 aqa a level
Study online at https://quizlet.com/_hegan6
8. Uncontrolled / rapid / abnormal (cell division);
9. Malignant tumour;
13. why would one area ( e.g wild ower meadow) have a higher species diversity
than another e.g potato field ? (5): 1) there would be more plant species
2) hence more habitats
3) more niches
4) more food sources
5) the area is able to support more biomass
14. describe competitive and non-competitive inhibition of enzyme ? (6): competitive
inhibitor
1) inhibitors reduce binding of enzyme to substrate/prevent formation of e-s complexes
2) inhibitor similar shape to substrate binds to active site of enzyme
3) inhibition can be overcome by adding more substrate
non-competitive inhibitor
4) inhibitor binds to site on enzyme other than active site
5) prevents formation of active site/ changes shape of active site
6) cannot be overcome by adding more substrate
15. Meiosis: cell ÷ to form gametes
2 ÷ forming 4 haploid daughter cells
genetically non-identical due to crossing over and independent segregation (assortment)
crossing over- creates new combination of alleles
independent assortment - creates new combination of chromosomes
16. Mitosis: cell divides for growth and repair
2 genetically identical daughter cells
prophase - nuclear membrane breaks down and chromosomes condense
metaphase- chromosomes line up on the equator and spindle fibres attach to chromosome at the centromere
anaphase - centromeres split and chromatids move to opposite poles
, Biology aqa A level common questions, AQA A Level Biology Topic 5 Exa
Questions, biology paper 2 aqa a level
Study online at https://quizlet.com/_hegan6
telophase - nuclear membrane reforms, chromosomes uncoil and cell ÷by cytokinesis
interphase - cells grow and organelles multiply and dna replicates, organelles multiply ready to ÷
17. heart disease ? (6): atheroma is cholesterol
in artery wall
atheroma is linked to blood clot
blocks coronary artery ( artery supplying heart muscle/tissue/ cells)
reduces o2 supply to heart muscle/ tissues/cells
unable to respire so die
18. Meiosis: prophase 1 - nuclear membrane breaks down, chromosomes condense
metaphase 1 - homologous pair of chromosomes line up next to each other on the equator, spindle attaches to
chromosome at the centromere, crossing over chromatid takes place
anaphase 1 - homologous pairs seperate 1 to each pole ( independent assortment )
telophase 1 - nuclear membrane reforms, cell ÷ by cytokinesis
prophase 2 - nuclear membrane breaks down, chromosomes condense
metaphase 2- chromosomes line up on the equator and spindle attaches to chromosome at the centromere
anaphase 2 - centromere split, chromatids move to opposite poles
telophase 2- nuclear membrane reforms, chromosomes uncoil, cell ÷ by cytokinesis
19. natural selection? (6): 1) variation of phenotypes in population due to random mutations
2) individuals that do not show behaviour die
3) change in selection pressue- environmental change
4) allele frequency increases in population
5) those who have the advantageous alleles, survive and reproduce and pass on their alleles giving a selective advantage
to their ottspring
6) until all individuals show the phenotype frequency of alleles in the population changes
20. tissue fluid? (6): high b.p/h.p
forces h2o out
large proteins remain in capillary
low w.p in capillary
due to plasma proteins
h2o enters capillary by osmosis
