AS & A Level Biology (9700) — May–June 2023, Paper 43
10 questions · every question answerable online with instant point-by-point AI marking against the official mark scheme.
Start with Question 1 →The Krebs cycle was named after the biochemist Sir Hans Krebs, who worked out the sequence in 1937. Fig. 1.1 is an outline of the Krebs cycle: acetyl coenzyme A (2C) combines with…
Answer this question and get it marked →Humans use antibiotics to treat bacterial infections. The increased use of antibiotics has led to an increase in the number of strains of bacteria that are resistant to…
Answer this question and get it marked →An example of control of gene expression in prokaryotes is regulation in the lac operon. The lac operon is a length of DNA that is made up of different parts. Fig. 3.1 shows a…
Answer this question and get it marked →Suggest and explain why it may be more appropriate to use enzyme replacement therapy to treat SCID instead of a bone marrow transplant.
Answer this question and get it marked →Table 5.2 shows the observed numbers obtained of each of the four different phenotypes for the F2 generation, compared with the numbers expected for a normal dihybrid ratio. Table…
Answer this question and get it marked →Fig. 6.1 shows part of the Bowman's capsule of a kidney nephron (not to scale). It shows the lumen of a capillary and the lumen of the Bowman's capsule, with three structures…
Answer this question and get it marked →Sarcomeres are the functioning units of the myofibrils of the muscle fibres (muscle cells) of striated muscle. The arrival of an action potential at the sarcoplasmic reticulum of…
Answer this question and get it marked →Fig. 8.1 is a diagram of a chloroplast, with four structures labelled K, L, M and N (K is the outer envelope membrane region, L is a thylakoid membrane, M is the thylakoid space,…
Answer this question and get it marked →Dopamine is a neurotransmitter released in some synapses in the brain. The release and action of dopamine is similar to that of acetylcholine. Fig. 9.1 is a diagram of a brain…
Answer this question and get it marked →The moose and the watermilfoil belong to the domain Eukarya, which includes the kingdoms Animalia and Plantae. Describe the main differences between the kingdom Animalia and the…
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