AQA A LEVEL BIOLOGY ACTUAL TEST PAPER
PREMIUM SOLVED QUESTIONS FULL
SOLUTION ALREADY PASSED
◉ The evaporation of water from the leaves of a plant results in
columns of water being filled up through its narrow xylem vessels
Explain why this column of water doesn't break (3 marks). Answer:
Water molecules are polar
Form hydrogen bonds between water molecules
Cohesion prevents breakage of columns
◉ Explain why water is considered so important for life to occur (6
marks). Answer: 1. Life (thought to have) evolved in water
2. Water provides support for bodies of organisms
3. Water is a major component of the cytoplasm
4. Water is a universal solvent
5. Water is a metabolite in metabolic reactions (condensation,
hydrolysis)
6. Water stabilises external temperatures
7. Water important in cooling internal temperature of organisms
◉ Most substances contract when they cool. Water is unusual, as it
freezes, it expands and becomes lighter.
PREMIUM SOLVED QUESTIONS FULL
SOLUTION ALREADY PASSED
◉ The evaporation of water from the leaves of a plant results in
columns of water being filled up through its narrow xylem vessels
Explain why this column of water doesn't break (3 marks). Answer:
Water molecules are polar
Form hydrogen bonds between water molecules
Cohesion prevents breakage of columns
◉ Explain why water is considered so important for life to occur (6
marks). Answer: 1. Life (thought to have) evolved in water
2. Water provides support for bodies of organisms
3. Water is a major component of the cytoplasm
4. Water is a universal solvent
5. Water is a metabolite in metabolic reactions (condensation,
hydrolysis)
6. Water stabilises external temperatures
7. Water important in cooling internal temperature of organisms
◉ Most substances contract when they cool. Water is unusual, as it
freezes, it expands and becomes lighter.
