AP BIOLOGY

Detailed explanation-1: -Endocrine glands make chemicals called hormones and pass them straight into the bloodstream. Hormones can be thought of as chemical messages. From the blood stream, the hormones communicate with the body by heading towards their target cell to bring about a particular change or effect to that cell.

Detailed explanation-2: -Endocrine signals travel through the bloodstream to reach target tissues and cells. Signals that originate in one part of the body and travel to their target through the bloodstream are called hormones.

Detailed explanation-3: -The “target” cells for a particular hormone have receptors, either on the cell membrane, or the case of lipid soluble hormones that can pass through the membrane, inside the cell. Only the cells that have the special receptors for that hormone will respond to exposure.

Detailed explanation-4: -The correct answer is c. Hormones are chemical signaling molecules that are produced and secreted by glands of the endocrine system. Hormones travel throughout the human body in the blood, exerting physiological responses from cells called target cells.

Detailed explanation-5: -Endocrine glands release hormones into the bloodstream. This lets the hormones travel to cells in other parts of the body. The endocrine hormones help control mood, growth and development, the way our organs work, metabolism, and reproduction. The endocrine system regulates how much of each hormone is released.