2017 HKDSE Integrated Science Paper 1 Q. 2, 3, 9,10 Paper 2 Q. 2 10 November 2017

Paper 2B

Paper 1

Paper 1

Q. 2, 3, 9,10

2

- Poor performance - overlooked the information of the question: BTX inhibits the release of neurotransmitters from the neurones

− Some candidates overlooked the requirement of the question: different variations in blood glucose level

9

b

c

- Poor performance - Failed to point out the importance of creating the same sticky ends to join the plasmid and the viral gene segment by complementary base pairing

- Unsatisfactory performance - Recombinant DNA technology involves ligation as well as gene isolation

- Unsatisfactory performance - misunderstood the question: to explain why instead of how the foreign viral gene can be expressed in the new host

- Unsatisfactory performance - Confused vaccine with antibiotics - vague answers such as disrupting the food chain

- Fair performance - focusing only on producers or decomposers in the flow of energy and cycling of materials OR discussing the role of consumers instead of decomposers - not realizing that energy flow is one-way and eventually lost to the surroundings - discussing only on the nitrogen cycle, but not the carbon, oxygen cycle and the water cycle

Paper 2

Q. 2

a

- Fair performance - Failed to realize how a heart attack is related to the blockage of the coronary arteries

- Good performance - Some wrongly proposed using ‘common chopsticks’ instead of ‘serving chopsticks’

- Poor performance - overlooked the information of the question: the women who gave birth were screened to identify the HBV carriers, but not the babies born

- Fair performance - Failed to point out that it is the net loss of bone upon aging that causes the decline in bone minerals

- Fair performance - Did not mention that calcium is the mineral that gives strength to bones and that the calcium absorption is assisted by vitamin D. - misconception that little outdoor exercise would cause a faster rate of bone material loss instead of a smaller peak bone mass

Thanks.