You don't specify which organism you are asking about, but I assume you mean in humans. These processes happen all over the body between the blood capillaries and the cells. If you mean exchange with the outside world, then oxygen is exchanged in the lungs, food nutrients in the small intestine, and nitrogenous waste in the kidneys. However, waste carbon dioxide is exchanged through the lungs and other wastes through the skin.
Capillary.capillariesCapillaries.Blood flow moves from arteries, to arterioles, to capillaries, to venules, to veins, to the heart, and then back to arteries. Capillaries are where the exchange of oxygen and other materials happens.Capillaries
The exchange of nutrients and oxygen does not take place in the heart. The exchange of oxygen takes place in the alveoli of the lungs and the exchange of nutrients takes place at numerous sites around the body, but the most predominant is the duodenum and ileum of the small intestine.
Kidneys
Capillaries
artria
Its all diffusion.
Nutrient exchange takes place in small blood vessels called capillaries, which have thin walls that allow for the exchange of gases, nutrients, and waste products between the blood and surrounding tissues.
The exchange of substances between the mother and embryo takes place in the placenta. The placenta is a temporary organ that develops during pregnancy to provide nutrients and oxygen to the embryo and remove waste products. This exchange is crucial for the growth and development of the embryo.
Pure diffusion ... everything flows from high concentration toward low. No energy is expended in these exchanges.
the wall of the uterus where oxygen, nutrients, and waste exchange takes place between the mother and fetus
Blood carries oxygen, nutrients, hormones, and waste products. The exchange of substances between blood and body tissues occurs in the capillaries, which are tiny blood vessels with thin walls that allow for the transfer of molecules. Oxygen and nutrients are delivered to tissues, while waste products are picked up and taken away by the blood for disposal.
Pure diffusion ... everything flows from high concentration toward low. No energy is expended in these exchanges.