Pituitary, Hypothalamus, Gonads

2 parts of pituitary gland

Anterior pituitary - controlled by hypothalamic neurohormones that travel via blood

Posterior pituitary - contains axons of hypothalamic neurons that release neurohormones

Hypothalamic neurons secrete 2 neuro-hormones into _____

Posterior pituitary

(ADH and Oxytocin)

Anterior pituitary secretes 4 ____ hormones that ____

Tropic hormones that control other endocrine glands

• Thyrotropin

• Luteinizing hormone

• Follicle-stimulating hormone

• Corticotropin

Hypothalamus controls Anterior pituitary by ____

Releasing hormones that reach the anterior pituitary via the portal blood vessels

Negative feedback in the anterior pituitary

Anterior pituitary cells are also controlled by negative feedback caused by the hormones of the target glands they stimulate

Hypothalamus axon location

Posterior pituitary

Pituitary and hypothalamus act as a _____

Connecter between the nervous system and the endocrine system

Gonads produce

Gametes and steroid hormones

Steroid hormones (produced by the gonads)

Androgens, Progesterone, and Estrogen

Androgen

Male steroid hormone

dominate form is testosterone

Progesterone and estrogen

Female steroid hormone

dominate form of estrogen is estradiol

Steroid hormones determine what in development?

Phenotypic male or female

Male vs Female testosterone

Both synthesize testosterone

females use testosterone to make estradiol with an enzyme called aromatase

Gonad activity is controlled by

Gonadotropins (from the anterior pituitary)

• Luteinizing hormones

• Follicle-stimulating hormones

Gonadotropins are controlled by

Hypothalamic gonadotropin releasing hormone (GnRH)

Increase in Gonadotropins leads to

Increase level of sex steroids