Question

describe how air in water reaches capillaries in the gill filament

Answer 1

• Water flows over the gill filaments: As water flows over the gill filaments, oxygen from the water diffuses into the blood vessels in the gill. At the same time, carbon dioxide from the blood in the gill diffuses into the water.
• Countercurrent flow: The direction of flow of water over the gill filaments is opposite to the flow of blood in the capillaries of the gill. This countercurrent flow helps to maximize the transfer of oxygen from the water into the blood and carbon dioxide from the blood into the water.
• Oxygen diffusion: The oxygen in the water diffuses into the capillaries in the gill filaments, where it is transported by the blood to the rest of the body. This oxygen is used by the cells in the body to produce energy through cellular respiration.
• Carbon dioxide removal: At the same time, carbon dioxide in the blood diffuses into the water, where it is carried away and expelled from the body.