Oxygen liberated during photosynthesis comes from

Assume that you are a veterinary surgeon and you have removed a significant length of the small intestine of a bear suffering from an intestinal tumour. After its recovery,would you suggest a plant-based or a meat-based diet for the bear? Provide a reason for your answer.

Why do ventricles have thicker walls than atria?

Single circulation,i.e.,blood flows through the heart only once during one cycle of passage through the body,is exhibited by:

Why does absorption of digested food occur mainly in the small intestine?

Explain,giving any three reasons,the significance of transpiration in plants.