AS & A Level Biology (9700) — May–June 2025, Paper 44
10 questions · every question answerable online with instant point-by-point AI marking against the official mark scheme.
Start with Question 1 →The kidneys play a role in osmoregulation. Antidiuretic hormone (ADH) is involved in osmoregulation. Describe how a decrease in blood water potential leads to an increase in ADH…
Answer this question and get it marked →Some inherited diseases are caused by mutations in genes. Huntington's disease is caused by a mutation in the HTT gene that codes for the huntingtin protein. Using Huntington's…
Answer this question and get it marked →Manx cats are domestic cats that can be either tailless or tailed. A survey of domestic cats in a town found that 6.8% of cats had tails (homozygous recessive, tt). Using the…
Answer this question and get it marked →Table 4.1 shows some features of four kingdoms. The features listed are: can be unicellular, have cell walls, can be autotrophic. Complete Table 4.1 by writing yes or no for each…
Answer this question and get it marked →Scientists used genetic engineering techniques to modify the malaria mosquito, Anopheles stephensi. In the modified A. stephensi, a gene called tTav is expressed in the cells of…
Answer this question and get it marked →Salamanders are amphibians that live in both terrestrial and aquatic habitats. They are found in many different environments. Different populations of salamanders have evolved in…
Answer this question and get it marked →Rice, Oryza sativa, can grow in flooded fields. Aerenchyma is a tissue found in the roots of rice. The development of aerenchyma is stimulated by flooding. Scientists grew rice…
Answer this question and get it marked →Fig. 8.1 is a transmission electron micrograph (TEM) of striated muscle. Three regions are visible: a light-coloured region (P), a medium-coloured region (Q), and a darker region…
Answer this question and get it marked →Photosynthesis involves both the light-dependent stage and the light-independent stage. Describe non-cyclic photophosphorylation.
Answer this question and get it marked →A hummingbird feeds on nectar but also eats insects. Scientists measured the respiratory quotient (RQ) of a hummingbird every 10 minutes over 120 minutes. Define the term…
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