13.10 The Gonads

gonads

• gamete-producing glands

• these are ovaries in females and testicles in males

puberty

• the process of physical changes by which a child’s body becomes an adult body that is capable of reproducing

• it is marked by maturing of the genital organs, the development of secondary sex characteristics, and the first occurrence of menstruation in the female

estrogen

a hormone secreted by the ovaries that is important in the development and maintenance of the female secondary sex characteristics and in regulation of the menstrual cycle

progesterone

• the hormone released during the second half of the menstrual cycle by the corpus luteum in the ovary

• its function is to complete the preparation of the uterus for possible pregnancy

gamete

• a reproductive cell

• these are sperm in the male and ova (eggs) in the female

gonadotropin

any hormone that stimulates the gonads

androgens

• sex hormones, primarily testosterone, secreted by the gonads, the adrenal cortex, and fat cells

• promote the development and maintenance of the male sex characteristics

testosterone

a steroid hormone secreted by the testicles and the adrenal cortex to stimulate the development of male secondary sex characteristics

steroids

• a large family of hormone-like substances that share the same fat-soluble chemical structure

• ex: cholesterol, testosterone, and anti-inflammatory corticosteroids such as prednisone

anabolic steroids

• man-made substances that are chemically related to male sex hormones

• they are used in the treatment of hormone problems in men and to help the body replace muscle mass lost due to disease

• athletes sometime use _______________ illegally to build muscle mass, a dangerous practice that can lead to lasting damage to the body

leptin

a protein hormone secreted by fat cells that is involved in the regulation of appetite

ghrelin

• a hormone produced in the gastrointestinal tract

• sometimes referred to as the hunger hormone, research is ongoing to flesh out the role that leptin and ______ play in rising levels of obesity

neurohormones

• produced and released by neurons in the brain, rather than by the endocrine glands, and delivered to organs and tissues through the bloodstream

• ex: secreted by the hypothalamus that control the secretions of the pituitary gland