Reproduction and Heredity Chapter 18 Reproduction and Heredity

The Endocrine System Endocrine glands- glands that produce and release chemicals Hormones- chemical substances produced by endocrine glands.

The Pituitary Gland small gland at the base of the brain Controls growth rate, metabolism, and reproduction Called the “master gland” because it regulates many other endocrine glands

Hypothalamus Controls the pituitary gland Regulates body temperature, use of water, and blood pressure Oversees many of the hormone levels in the body

Adrenal Glands Produce hormones that affect the functioning of your kidneys, your metabolism, and your response to stressful situations Adrenaline – hormone important in the fight or flight response

Thyroid Gland Releases a hormone that regulates metabolism Releases a hormone that regulates the amount of calcium in the blood

Parathyroid Gland 4 tiny glands attached to the back of the thyroid that regulates levels of calcium and phosphorus.

Pancreas Located behind the stomach Part of two systems – digestive and endocrine In the endocrine it controls the level of sugar in the blood. Improper function can cause: Diabetes—level of sugar too high or Hypoglycemia—level of sugar too low.

Thymus Function not thoroughly understood. Plays a role in developing some of the body’s defenses against infection.

Reproduction and the Endocrine System Ovaries – reproductive glands in females Testes – reproductive glands in males Follicle-stimulating hormone (FSH) Luteinizing hormone Two hormones produced by the pituitary gland that begin that process of sexual maturation in adolescents

Reproduction and the Endocrine System In males, testosterone and FSH control production of sperm, the male sex cells. Testosterone is also responsible for developing and maintaining other male traits such as deepening voice and body hair In females, two female sex hormones, progesterone and estrogen are produced by the ovaries. They are responsible for developing other female traits such as breast development and widening of the hips In addition, progesterone and estrogen work with FSH and LH to produce ova or eggs.