Question

Different groups of animals have evolved different organs to take in oxygen and send out carbon dioxide; but they all have certain common characters. Mention four such characters.

Answer 1

Different organisms have different ways of obtaining oxygen from the surrounding atmosphere and releasing carbon dioxide to the atmosphere but they all share:

• Process of diffusion-for the gas exchange

• The circulatory system within the respiratory organs (rich in blood capillaries)

• The respiratory surface-thin and can be increased

• Protection of respiratory organs.