Explain two properties of water that are vital for aquatic life and explain how these arise
Ice floats on water as it is less dense- due to lattice structure of water molecules in ice. This insulates the water below the ice, preventing it from freezing to ensure marine life has suitable temperature. Water has large thermal heat capacity (lots of energy required to raise its temperature) as strong hydrogen bonds must be broken to increase temperature. Keeps temperature stable.
AA
Related Biology A Level answers
All answers ▸Describe the pathway of electrical activity in the heart during contraction.
(b) Cigarette smoke contains nicotine. Nicotine is a vasoconstrictor that reduces the diameter of some blood vessels. (i) Using this information, explain why smoking increases the risk of developing cardiovascular disease (CVD). How do I approach this?
Relate the structural adaptations of lumbar vertebrae to their functions (6 mark).
Why do large organisms need specialised exchange systems and what are the features of an efficient exchange surface?