Growth factors and cytotoxic factors also regulate inflammatory response. These cytokines and other chemicals recruit immune cells to the site of infection and promote healing of damaged tissue following the removal of pathogens. NFkB plays a key role in regulating the immune response to infection.
Stomata facilitate the exchange of gases in the leaf. Carbon dioxide (CO 2 ) diffuses into the leaf through the stomata for use in photosynthesis, and oxygen (O 2 ), the waste product of photosynthesis, diffuses out of the leaf through stomata. Stomata are also crucial for water transport through the xylem .
Both male and female reproductive organs have internal and external structures. Reproductive organs are considered to be either primary or secondary organs. The primary reproductive organs are the gonads (ovaries and testes), which are responsible for gamete (sperm and egg cell) and hormone production.