Chapter 13- Endocrine System Flashcards
Hormones
Chemicals secretes by glands and specialized cells of the endocrine system
30 hormone genes
Steroid hormones
Synthesized from cholesterol
Male and female sex hormones, aldosterone
Easily pass through a cell membrane and triggers synthesis of new proteins
Nonsteroid hormones
Protein based hormones
Synthesized from amino acids
Further divide into:
Protein hormones(insulin)
Peptide hormones(antidiuretic hormone)
Amino acid hormones (epinephrine and norepinephrine)
Bind to receptors on cell surface, activates second receptor which activates a specific enzyme which causes a reaction
Anterior pituitary
Tropic hormones
Stimulate other endocrine cells to release hormones
Growth hormone
Anterior
GH
Growth and repair of tissue through breakdown of proteins and fat
Prolactin
Anterior
PRL
Milk secretion
Thyroid stimulating hormone
Anterior
TSH
Growth of thyroid and secretion of thyroid hormones
Adrenocorticotropic hormone
Anterior
ACTH
Growth and secretion of corticosteroids by adrenal gland
Follicle stimulating hormone
Anterior
FSH
Growth of ovarian follicles and secretion of estrogen
Sperm production
Luteinizing hormone
Anterior
LH
Ovulation and sperm secretion
Posterior pituitary gland
Stores hormones
Antidiuretic
Posterior
ADH
Water retention
Oxytocin
Posterior
OT
Uterine contractions, secretion of milk
Pineal gland
Behind thalamus
Produces melatonin
Thymus
Secretes thymosin and thymopoietin
Developers of the immune system
Lies just beneath the sternum
Thyroid gland
Larges endocrine gland
Two large loves connected by a narrow tissue (isthmus)
Can store hormones for later use
Calcitonin, T3 & T4 (rate of metabolism)
Parathyroid glands
Posterior surface of the thyroid
PTH in response to low blood calcium levels
Pancreas
Acts as both endocrine and exocrine glands
Gonads
Testes-testosterone
Ovaries- estrogen (female characteristics), progesterone(uterine lining for pregnancy)
Lymphatic function
Maintenance of fluid balance- absorbs leftover fluid that seeps out of capillaries
Absorption of fats- absorb fats and fats soluble vitamins
Immunity- lymph removes cellular waste, microorganisms, and foreign particles
Spleen
Fist sized
Body’s largest lymphatic organ
Immunity- white pulp screens blood for antigens
Destruction of old red blood cells- digest old cells and return iron and globin to bone marrow and liver for future use
Blood storage- stores 20%-30% of the body’s platelets
Hematopoiesis- produces red blood cells in the fetus
