Endocrine Lab Flashcards
Tendency of living body to maintain relatively stable conditions in spite of changes in the external environment
Homeostasis
What is homeostasis also referred to as?
Dynamic steady state
Communication and coordination between cells to maintain homeostasis
Cell signaling
What is the function of the endocrine system?
produce and secrete hormones that regulate activity of cells and organs to maintain homeostasis
Secretes hormones into bloodstream
Endocrine
Secretes products through ducts to external environment
exocrine
The function of these hormones is to stimulate the production and secretion of hormones by targeting endocrine glands
Tropic hormones
Cell signaling: a cell targets a distant cell through the blood stream
Endocrine
Cell signaling: a cell targets a nearby cell
Paracrine
Cell signaling: a cell targets itself
Autocrine
Does endocrine or nervous system send faster signals?
nervous
Do nervous signaling or hormone effects have a longer duration of effect?
hormone effects
Pituitary, Pineal, Thyroid, Parathyroid, Thymus, Adrenal, Gonads, Pancreas
Endocrine glands
Which pituitary gland has glandular epithelial tissue?
anterior
Which pituitary gland has nervous tissue?
posterior
What hypothalamic hormones are stored in posterior pituitary gland?
OT and ADH
OT
oxytocin
ADH
anti-diuretic hormone
How is posterior pituitary gland connected to hypothalamus?
nerve axons
How is anterior pituitary gland connected to hypothalamus?
portal system
HGH
human growth hormone
TSH
thyroid-stimulating hormone
FSH
follicle-stimulating hormone
LH
luteinizing hormone
PRL
prolactin
ACTH
adrenocorticotropic hormone
MSH
melanocyte-stimulating hormone
What hormones does the anterior pituitary gland create and secrete?
HGH, TSH, FSH, LH, PRL, ACTH, MSH
Stimulates widespread tissue growth
Produced in anterior pituitary
targets most tissues, especially bone, skeletal muscle, liver, cartilage, fat
HGH
Stimulates growth of thyroid gland and secretion of its hormones
Produced in anterior pituitary
Targets thyroid gland
TSH
Stimulates sperm/oocyte production and estrogen secretion
Produced in anterior pituitary
Targets testes and ovaries
FSH
Triggers ovulation in females and testosterone secretion in males
Produced in anterior pituitary
Targets testes and ovaries
LH
Stimulates milk synthesis
Produced in anterior pituitary
Targets mammary glands
PRL
Stimulates growth of adrenal cortex, secretion of glucocorticoids
Produced in anterior pituitary
Targets adrenal cortex
ACTH
Promotes water retention
Produced in hypothalamus
Stored in posterior pituitary
Targets kidneys
ADH
Stimulates uterine contractions and milk release during suckling (birth)
Produced in hypothalamus
Stored in posterior pituitary
Targets uterus and mammary glands
OT
Secretes melatonin
Influences mood, sexual maturation, circadian rhythm
Targets other brain areas
Pineal gland
secretes T3 & T4 (triiodothyronine and thyroxine)
Increases metabolic rate and heat production
Targets most tissues
Thyroid gland
In the thyroid, C cells (parafollicular cells) secrete what hormone that targets osteoclasts in bone?
inhibits osteoclasts and deceases blood calcium levels
Calcitonin
PTH
parathyroid hormone
Secretes PTH
Stimulates osteoclasts, increasing blood calcium levels
Targets osteoclasts in bone
parathyroid glands
Anterior to heart and undergoes involution
Secretes thymosin
Stimulates T lymphoocyte development and activity
Targets T cells
thymus
What gland is divided into cortex and medulla?
adrenal gland
Which division of the adrenal gland is divided into 3 zonas and has glandular tissue?
Adrenal cortex
Which division of the adrenal gland has nervous tissue and is directly innervated by the nervous system?
Adrenal medulla
What zona of the adrenal cortex secretes aldosterone and mineralcorticoids? (outermost)
Zona glomerulsa
What zona of the adrenal cortex secretes cortisol and glucocorticoids? (middle)
Zona fasciculata
What zona of the adrenal cortex secretes DHEA and androgens? (deepest)
Zona reticularis
What hormones/neurotransmitters does the adrenal medulla secrete?
E and NE
Most superficial
Secretes aldosterone (mineralocorticoids)
Targets Kidneys
Increases sodium and water reabsorption (prevent Na/H2O excretion in urine); maintains blood pressure and volume
Zona glomerulosa
Secretes cortisol (glucocorticoid)
Targets most tissues of the body
Promotes stress resistance, stimulates fat and protein catabolism, gluconeogenesis, tissue repair
Zona fasciculata
Most deep
Secretes androgens like dehydroepiandrosterone (DHEA)
Targets many tissues of the body
Indirectly promotes growth of bones, pubic/axillary hair, apocrine glands; stimulates libido
Zona reticularis
Secretes epinephrine and norepinephrine
Targets almost all tissues
Promotes fight or flight responses
Adrenal medulla
A neuroendocrine tumor that affects medulla
Grows from chromaffin cells in medulla
Symptoms: high blood pressure, headache, sweating, symptoms of panic attack
Results in high adrenaline
Pheochromocytoma
Produce endocrine and exocrine products
Made in ovaries
Targets uterus, mammary glands, and other tissues
Stimulates female reproductive cycle, regulates menstrual cycle and pregnancy
Estradiol
Made in ovaries
exocrine hormone
Targets uterus and mammary glands
Regulates menstrual cycle and pregnancy
Exocrine product is an egg
Progesterone
Male reproductive gonads
Produce endocrine and exocrine products
Testes
Targets testes, muscles, and other tissues
Stimulates male reproductive development, sperm production, and libido
exocrine product is sperm
Testosterone
What are the endocrine products of the pancreas?
insulin and glucagon
What are the exocrine products of the pancreas?
Digestive enzymes
Produced by alpha cells in Islet of Langerhans in pancreas
Targets liver
Stimulates breakdown of glycogen to glucose in liver and increases blood glucose
Glucagon
Produced by beta cells in Islet of Langerhans in pancreas
Targets most tissues
Decreases blood glucose levels by stimulating glucose uptake
Insulin
What is the system of assigning a number to carbohydrate-containing foods according to how much each food increases blood sugar
Glycemic index
What does a lower GI value mean?
slower carbohydrate
What is a low GI value?
less than 55
What is a medium GI value?
56-69
What is a high GI value?
greater than 70
What is the purpose of feedback loops?
to maintain homeostasis
feedback loop that brings a system closer to a target of stability
product of a reaction leads to a decrease in that reaction
negative feedback loop
feedback loop that moves a system further away from the target of equilibrium
product of a reaction leads to an increase in that reaction
leads to a massive response
stopped by getting rid of stimulus via external force
positive feedback loop