Lab Practical Review #1 Endocrine System ● Pineal Gland - little lump in the posterior part of the brain. Secretes melatonin to regulate circadian rhythm (sleep cycles). ● Hypothalamus - front part of large space in brain. Secretes GnRH (secretes FSH and LH), GHRH (secretes GH), CRH (secretes ACTH), TRH (secretes TSH), Melatonin (PrL secretion), MSH (MSH secretion), somatostatin (GH secretion) ● Pituitary Gland- underneath the hypothalamus, hangs from the thin stalk, the “infundibulum”, Anterior Pituitary secretes GH (growth, protein synthesis, lipid degradation), FSH and LH (sperm and ova development and secretion of sex hormones), ACTH (releases glucocorticoids from adrenal cortex), Prl (milk synthesis), TSH (stimulates release of thyroid hormones) and Posterior Pituitary secretes Oxytocin (uterine contractions, milk letdown reflex, and promotes fertility), and ADH (increases water reabsorption in the kidneys which increases blood volume and pressure) ○ Anterior “Adenohypophysis” is near the front of the face and Posterior “neurohypophysis” is near the back ● Thyroid Gland : right under thick thyroid cartilage of the larynx, 2 lobes (right and left- use orientation of the person), and isthmus is the middle which connects the two lobes. Secretes T3 and T4 which help with growth and differentiation and calcitonin which lowers blood calcium. ● Parathyroid Glands : 4 dots on the back of the thyroid gland, 2 on each lobe. Secretes PTH which increases blood calcium ● Adrenal Glands : On top of the kidneys which are at the back of the body, 2 hanging. Cortex is the outer part and medulla is the inner part. Adrenal Cortex secretes
mineralocorticoids (aldosterone) which increase renal absorption of sodium and elevates blood pH, glucocorticoids (cortisone), which increases stress tolerance and blood glucose and decreases inflammation, and gonadocorticoids (androgens and estrogens) and these provide each sex with the hormones of the other sex. The adrenal medulla secretes catecholamines (E and NE) which make effects of sympathetic nervous system global and long lasting for survival during immediate or extreme stress. ● Ovaries/ Testes: Ovaries: secretes estradiol and progesterone which is female sexual development and behavior as well as uterine and mammary growth and maternal behavior. Testes: testosterone which is for male sexual development and behavior and Inhibin which is for Pituitary FSH secretion.
- Spring '17
- Endocrine System