Endocrine System

Functions of the endocrine system

• Regulates the effects of hormones on the body functions.

• Controls growth, development metabolism and maintaining homeostasis.

• Works closely with the nervous system. Nerve impulses direct the secretion of hormones.

Hormones• The chemical regulators

of the body that have a particular effect on the growth or function of a body part.

• Hormones are secreted by glands, groups of cells that manufacture secretions and store them until triggered to release them.

• Glands also produce other substances such as sweat and oils which are not hormones.

Types of Glands

• Exocrine glands: secrete substances through a duct into a body cavity or onto the skin’s surface.

– Examples: sweat glands and mammary glands (THESE ARE NOT PART OF THE ENDOCRINE SYSTEM)

Types of Glands• Endocrine glands: secrete hormones in small amounts

directly into the bloodstream. • Specific hormones effect specific body parts.• They travel through the bloodstream until they reach their

target cells (they cell that the hormone acts on)• Hormones do NOT affect other cells other than the target

cells.

Hormones & Functions• Insulin: produced by the pancreas and

regulates the amount of glucose in the blood.

• Growth hormone: secreted by the pituitary gland in the brain, controls body growth and activities of other glands.

• Adrenaline: secreted by adrenal glands, responds to stress (fight or flight response)

• Thyroxin: secreted by thyroid gland, responsible for metabolism

Hormones & Functions

• Parathyroid gland: regulates the amount of calcium in the blood.

• Hypothalamus: maintains body temperature, sleeping, eating, and balancing water

• Ovaries & Testes: secrete reproductive hormones.