AP BIOLOGY

Detailed explanation-1: -Most secretions are internal, but some are both external and obvious-e.g., tears and sweat. The gastric glands lining the stomach include four different types of cells that secrete substances necessary to digestion. Endocrine glands secrete hormones directly into the bloodstream to be carried to their sites of action.

Detailed explanation-2: -(secretion) Body substance in a liquid or semisolid state produced by an exocrine gland. Example: saliva, sebum, blood, plasma, semen, urine. Endogenous substances produced through the activity of intact cells of glands, tissues, or organs.

Detailed explanation-3: -About Hormones are secreted from the glands of the endocrine system, they are specific in that each hormone causes a response in a specific target organ or group of cells, rather than on the body as a whole. Exocrine hormones are secreted via a duct into the blood and usually effect a distant organ or tissue.

Detailed explanation-4: -Endocrine glands secrete hormones straight into the bloodstream. Hormones help to control many body functions, such as growth, repair and reproduction. The endocrine system involves many organ systems and hormones, many of which are still being investigated and understood.

Detailed explanation-5: -The three mechanisms by which exocrine glands release their secretions include merocrine, apocrine, and holocrine.