2016 Unit 2 aqa biology unofficial mark scheme!! 2016

ANAEROBIC RESPIRATION!
1a) what is meant by anaerobic ?(1)
a) The release of energy by the break down of glucose molecules ( main point needed ---> WITH NO OXYGEN PRESENT

1b) Use figure 1 to describe what happened during the respiration ( the bar chart ) ? (2)
a) starts off low lactic acid as runners still breathing in oxygen. Then lactic acid level increases as he runner is intaking oxygen, making the body convert glucose into lactic acid this also causes oxygen debt !!

1c) how long did the runner run for ? (1)
a) 1.4/1.5 minutes ( A LOT OF PEOPLE GOT THEM BOTH BECAUSE THE LINE WASN'T VERY ACCURATE )

1d) How does the increase in rate of blood pressure o the muscle help the athlete? (4)
a) ( IT GAVE A GRAPH ) - its aerobic respiration , the more oxygen he breathed in the more the blood pressure went to his muscles, also the oxygen made more glucose molecules break down releasing more energy ( possibly making adrenaline hormones e.g. insulin )

2) PONDWEED QUESTION 6 MARKS ! ( EQUIPMENT GIVEN AS A DIAGRAM )
a) - taping the pondweed to the ruler
-placing in beaker with water near window so chlorophyll can absorb sunlight
-try different temperatures to vary results
- GIVE A DIFFERENT METHOD EG... water in beaker, place pondweed in water, attach the glass tube to test tube and count after every 1 minute how much oxygen create, put at different temperatures and different distances from light energy etc...

3a) what does an enzyme work best at - cell membrane - cytoplasm - nucleus ? (1)
a) cytoplasm

3ai) what is an enzyme ? (2)
a) biological catalyst, made from proteins, speeds up chemical reactions

3b) what organ system is the stomach part of (1)
a) digestive system

3bi) what does the epithelial tissue do ? (1)
a) protects the inner and outer lining of the stomach

3bii) what does the glandular tissue do ? (3)
a) produces digestive juices, produces hormones, produces enzymes or secretes them

MESSAGE ME OR COMMENT THE REST OF THIS QUESTION PLEASE

4) The maths question - IF YOU HAVE THE ANSWERS COMMENT THEM (3)

4a) 3 ways to improve the experiment ? (3)
1 - Use a random sample instead of being specific
2 - Use a more populated species so you get more varied and larger results
3 - Take more samples so you have a wider range of results and averages will be easier to predict

5) the chromosomes are heterozygous so why could he of still got polydactyl ?
a) heterozygous means the chromosomes are the same so that increases the chances also during mitosis the chromosomes are diploid doubling the chances again and in meiosis the chromosones cross over and swap DNA meaning both chromosones could have the disease.

5ai) what is the probability of him having polydactyl ?
a) 1/2 - 50 %


REST OF QUESTION NOT COMPLETE COMMENT THE ANSWERS AND QUESTIONS...

6) Give the advantages and disadvantages of using hydrogen peroxide and catalyse ? (2)
a) 1- ad- catalyse - catalysts can be re-used repeatedly, hydrogen peroxide - it can work towards killing dangerous bacteria
2- disadvantages - catalyse - catalysts denature some at very low temperature so wouldn't work very well, hydrogen peroxide - it can remain in the milk becoming dangerous to us and it doesn't actually fully kill the bacteria - not effective

COMMENT THE REST OF THIS QUESTION

7 ) Don't know if this was the right question, but - what is the process taking place here ? DIAGRM OF A TYPE OF CELL DIVISION GIVEN ... (1)
a) meiosis

7b) Organ does this process take place ? (1)
a) gametes / testes ( either )

7bi) THIS WAS THE PUNNET TABLE QUESTION .... RED HAIR OR BROWN HAIR (3)
Father - B -------- mother b
B BB Bb
b Bb bb

COMMENT THE REST OF THIS QUESTION AND THE ANSWERS

8) How can scientists prove that the foxes are the same species? (2)
a) looking at tow of the different types of the same species and look at their DNA and genes, observing their appearance ( features ) and how they adapting.

8ai) How did the grey foxes spread over all 6 countries and exist now? (5)
a) - it was during the ice age, land would of frozen and close countries could of created land bridges for the foxes to separate
- Its speciation meaning a change in the environment made species adapt to their new surroundings
- involve survival of the fittest and how ones that have negative speciation or don't adapt will most likely die or not be able to reproduce

8b) How are grey foxes able to create completely different species of animal? (2)
a) because once adapted fully to the new surrounding they are still able to reproduce meaning they can reproduce with the new species of animal in the environment, which means new species will be reproduce and it will start generations of that animal.

IF I HAVE MISSED ANY THEN PLEASE MESSAGE ME OR COMMENT WHICH ONES I'VE MISSED :-)

The cell division was mitosis?

yea, i put mitosis not meiosis.

ANAEROBIC RESPIRATION!
1a) what is meant by anaerobic ?(1)
a) The release of energy by the break down of glucose molecules ( main point needed ---> WITH NO OXYGEN PRESENT


1b) Use figure 1 to describe what happened during the respiration ( the bar chart ) ? (2)
a) starts off low lactic acid as runners still breathing in oxygen. Then lactic acid level increases as he runner is intaking oxygen, making the body convert glucose into lactic acid this also causes oxygen debt !!

1c) how long did the runner run for ? (1)
a) 1.4/1.5 minutes ( A LOT OF PEOPLE GOT THEM BOTH BECAUSE THE LINE WASN'T VERY ACCURATE )

1d) How does the increase in rate of blood pressure o the muscle help the athlete? (4)
a) ( IT GAVE A GRAPH ) - its aerobic respiration , the more oxygen he breathed in the more the blood pressure went to his muscles, also the oxygen made more glucose molecules break down releasing more energy ( possibly making adrenaline hormones e.g. insulin )

2) PONDWEED QUESTION 6 MARKS ! ( EQUIPMENT GIVEN AS A DIAGRAM )
a) - taping the pondweed to the ruler
-placing in beaker with water near window so chlorophyll can absorb sunlight
-try different temperatures to vary results
- GIVE A DIFFERENT METHOD EG... water in beaker, place pondweed in water, attach the glass tube to test tube and count after every 1 minute how much oxygen create, put at different temperatures and different distances from light energy etc...

3a) what does an enzyme work best at - cell membrane - cytoplasm - nucleus ? (1)
a) cytoplasm

3ai) what is an enzyme ? (2)
a) biological catalyst, made from proteins, speeds up chemical reactions

3b) what organ system is the stomach part of (1)
a) digestive system

3bi) what does the epithelial tissue do ? (1)
a) protects the inner and outer lining of the stomach

3bii) what does the glandular tissue do ? (3)
a) produces digestive juices, produces hormones, produces enzymes or secretes them

MESSAGE ME OR COMMENT THE REST OF THIS QUESTION PLEASE

4) The maths question - IF YOU HAVE THE ANSWERS COMMENT THEM (3)

4a) 3 ways to improve the experiment ? (3)
1 - Use a random sample instead of being specific
2 - Use a more populated species so you get more varied and larger results
3 - Take more samples so you have a wider range of results and averages will be easier to predict

5) the chromosomes are heterozygous so why could he of still got polydactyl ?
a) heterozygous means the chromosomes are the same so that increases the chances also during mitosis the chromosomes are diploid doubling the chances again and in meiosis the chromosones cross over and swap DNA meaning both chromosones could have the disease.

5ai) what is the probability of him having polydactyl ?
a) 1/2 - 50 %


REST OF QUESTION NOT COMPLETE COMMENT THE ANSWERS AND QUESTIONS...

6) Give the advantages and disadvantages of using hydrogen peroxide and catalyse ? (2)
a) 1- ad- catalyse - catalysts can be re-used repeatedly, hydrogen peroxide - it can work towards killing dangerous bacteria
2- disadvantages - catalyse - catalysts denature some at very low temperature so wouldn't work very well, hydrogen peroxide - it can remain in the milk becoming dangerous to us and it doesn't actually fully kill the bacteria - not effective

COMMENT THE REST OF THIS QUESTION

7 ) Don't know if this was the right question, but - what is the process taking place here ? DIAGRM OF A TYPE OF CELL DIVISION GIVEN ... (1)
a) meiosis

7b) Organ does this process take place ? (1)
a) gametes / testes ( either )

7bi) THIS WAS THE PUNNET TABLE QUESTION .... RED HAIR OR BROWN HAIR (3)
Father - B -------- mother b
B BB Bb
b Bb bb

COMMENT THE REST OF THIS QUESTION AND THE ANSWERS

8) How can scientists prove that the foxes are the same species? (2)
a) looking at tow of the different types of the same species and look at their DNA and genes, observing their appearance ( features ) and how they adapting.

8ai) How did the grey foxes spread over all 6 countries and exist now? (5)
a) - it was during the ice age, land would of frozen and close countries could of created land bridges for the foxes to separate
- Its speciation meaning a change in the environment made species adapt to their new surroundings
- involve survival of the fittest and how ones that have negative speciation or don't adapt will most likely die or not be able to reproduce

8b) How are grey foxes able to create completely different species of animal? (2)
a) because once adapted fully to the new surrounding they are still able to reproduce meaning they can reproduce with the new species of animal in the environment, which means new species will be reproduce and it will start generations of that animal.

IF I HAVE MISSED ANY THEN PLEASE MESSAGE ME OR COMMENT WHICH ONES I'VE MISSED :-)

Are you sure on 1d? That's what I put too but people are saying its with lactic acid and oxidation?

yeah it's mitosis

Are you sure on 1d? That's what I put too but people are saying its with lactic acid and oxidation?

It clearly was meiosis it had 4 cells at the bottom

yeah it's mitosis

It clearly was meiosis it had 4 cells at the bottom

For what does the term anerobic mean?. Would I get a mark if I put that there isn't enough oxygen to break down the lactic acid.

The cell division was mitosis?

it was meiosis, they gave a diagram showing the cells being split up twice and that means the cells are haploid which means halved and that only happens in meiosis as the cells cleve and divide twice and give 4 daughter cella instead of mitosis which is diploid and they double and only divide once and give 2 daughter cells :-)

it was meiosis, they gave a diagram showing the cells being split up twice and that means the cells are haploid which means halved and that only happens in meiosis as the cells cleve and divide twice and give 4 daughter cella instead of mitosis which is diploid and they double and only divide once and give 2 daughter cells :-)