Answer:
Was there meant to be a picture?
The proteins that help defend the body against bacteria, toxins, and allergens are called antibodies. The antibody<span> (Ab) protein is also known as an immunoglobulin (Ig).
</span>These<span> large Y-shaped proteins are</span><span> produced by the immune system in order to prevent the body in response to the presence of a foreign substance. The foreign substance is called antigen.
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Conclusion this is how the nervous system in human
External respiration (correct answer) involves the exchange of oxygen and carbon dioxide within the environment.
The exchange of wastes through the skin is just called excretion by sweating.
There is no exchange of nutrients that occur in the lungs but rather absorption of nutrients is the function of the gastrointestinal tract.
The exchange of oxygen and carbon dioxide within the cell is called cellular respiration and involves carrying oxygen from the blood to the cell then the cell uses it as the final electron acceptor in the electron transport chain. The metabolic wastes of the cell, primarily carbon dioxide, goes now to the bloodstream to be exchanged for oxygen in the lungs.
