AS & A Level Marine Science (9693) — May–June 2025, Paper 43

5 questions · every question answerable online with instant point-by-point AI marking against the official mark scheme.

Start with Question 1 →
Question 1 · 14 marks · Cell biology / aquatic plant / light micrograph / nucleus / organelles

Fig. 1.1 shows a light micrograph of a cell from an aquatic plant. Structure X is labelled. Identify structure X.

Answer this question and get it marked →
Question 2 · 14 marks · Marine ecology / lionfish / invasive species / spearfishing / bycatch / reef damage / conservation

Lionfish (Pterois volitans) are an invasive species in the Caribbean Sea. They are not native to the area and have few natural predators. A conservation project in Mexico started…

Answer this question and get it marked →
Question 3 · 17 marks · Ocean acidification / carbon dioxide / carbonic acid / hydrogen ions / bicarbonate / pH

Ocean acidification is caused by increasing concentrations of carbon dioxide in the atmosphere. Describe how carbon dioxide reacts with water to increase acidity.

Answer this question and get it marked →
Question 4 · 15 marks · Osmoregulation / mangrove / osmosis / sucrose concentration / percentage change in mass / turgor pressure / line graph / plotting

A student investigated the effect of sucrose concentration on mangrove root cells. Table 4.1 shows the sucrose concentration, percentage change in mass of root sections and turgor…

Answer this question and get it marked →
Question 5 · 15 marks · Marine fish / ventilation / pumped ventilation / ram ventilation / buccal cavity / operculum / active / passive / movement

Sea trout use pumped ventilation to move water over their gills. Some fish, such as tuna, use ram ventilation. Outline how pumped ventilation differs from ram ventilation.

Answer this question and get it marked →

← May–June 2024 Paper 11 · May–June 2025 Paper 42 →

← All AS & A Level Marine Science (9693) past papers