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Question
Give Reasons
The full-grown human embryo respires but does not breathe.
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Solution
The full-grown human embryo respires because the dissolved oxygen in the mother’s blood diffuses into the embryo and is used in the oxidation of glucose in the cells with the liberation of energy. However there are no breathing movements as the lungs lie collapsed in the embryo and the only function after the fetus is expelled from the mother’s body. Therefore no breathing movements in the embryo as it receives oxygen by diffusion of gases.
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