Anatomy 310 Endocrine Exam

Nervous and endocrine systems are known for?

communication and coordination

What is a type of cell-cell communication?

gap junctions

Gap junctions allow?

direct chemical communication

Paracrine secretions allow?

local chemical communication

The endocrine and nervous system allow?

communication between distant cells

Where is the nuclei of the hypothalamus?

wall and floor of the 3rd ventricle

What primitive functions does the hypothalamus and hypophysis control?

water balance, temperature, sex drive, childbirth

What is the name for the anterior pituitary?

Adenohypophysis

What is the name for the posterior pituitary?

Neurophpophysis

What is the name of the stalk of the pituitary?

infundibulum

Which pituitary takes up 3/4's?

anterior

How is the anterior pituitary connected to the hypothalamus?

hypophyseal portal system (hps)

Why does the HPS bring hormones from the hypothalamus?

to regulate adenohypophysis secretion

How does the Neurohypophysis connect to the hypothalamus?

through neurons of the hypothalamo-hypophyseal tract

Where do neurons make and store hormones?

at the axon end

Neurons make and store hormones until?

signals depolarize them

What two hormones are stored in the posterior pituitary?

Antidiuretic hormone (ADH) and oxytocin (OT)

How many releasing hormones are in the hypothalamus?

4

How many inhibiting hormones are released in the hypothalamus?

2

What are gonadotropins?

hormones secreted by pituitary gonadotrope cells

What are two examples of gonadotropins?

FSH & LH

Do levels of hormones fluctuate?

Yes. Some at set times.

Growth hormone (GH) time of fluctuation?

low in day, peaks at night

Lutenizing hormone (LH) time of fluctuation?

peaks in mid menstral cycle

Oxytocin (OT) time of fluctuation?

peaks during labor and nursing

What is the anterior pituitary regulated in part by?

Hypothalamus

What controls the posterior pituitary?

neuroendocrine reflexes

When does OT peak from the posterior pituitary?

When the brain is stimulated by labor or nursing.

What happens during dehydration?

osmoreceptors in hypothalamus detect low water concentration in the blood

As a result of dehydration, what does the hypothalamus release?

ADH

What happens during the detection of high blood pressure?

stretch receptors in heart and arteries send a signal to hypothalamus indicating high bp

What is released by the hypothalamus as a result of high blood pressure?

ADH is not released

What are both lobes of the pituitary regulated by?

negative feedback inhibition

What is an example of negative feedback inhibition?

Hypothalamus and pituitary regulate the thyroid, and are in turn regulated by the thyroid hormone.

What is an example of positive feedback?

oxytocin during pregnancy

The pineal gland is large in what age?

children but shrinks (involutes) rapidly

What is the function of the pineal gland?

function is unclear

Damage or tumors on the pineal gland may cause?

premature sexual maturation

At night, what does the pineal gland produce?

melatonin

During the day, what does the pineal gland produce?

serotonin

What does melatonin and serotonin in the pineal gland regulate?

moods

The thymus is large in what age?

children (grows), then involutes.

What is the thymus in the elderly?

fatty and fibrous

What hormones does the thymus secrete?

thymopoietin and thymosin

What does thympoietin and thymosin aid in?

development and activation of T lymphocytes

Thymopoietin and thymosin supports?

lymphatic organs

What is the largest endocrine gland in adults?

thyroid

What gland has the highest high blood flow/gram?

thyroid

The follicular cells in the thyroid are what type of tissue?

cuboidal epithelium

The fluid in the follicle cells is mostly?

Triiodothyronine (T3) and Tetraiodothyronine (T4)

What hormone in the thyroid makes up 98%?

T4-which is the inactive form

Thyroid Hormones (TH) are secreted by?

follicular cells

Clear parafollicular cells are also known as?

C cells in the thyroid

What do C cells make?

calcitonin when blood calcium levels rise

What does calcitonin stimulate?

osteoblasts

Why is calcitonin important in children?

osteoclast suppression

What does the parathyroid make?

calcitrol when blood calcium is low

The adrenal glands are also known as?

Suprarenal glands

What does retroperitoneal mean?

Lying outside the peritoneal cavity between the peritoneum and posterior body wall

What organs/glands are retroperitoneal?

Adrenal glands and the kidneys

What are the adrenal glands formed by?

fusion of the medulla (nervous tissue) with cortex

The adrenal medulla gland arises from?

nervous tissue

What does the adrenal medulla have?

preganglionic and postganglionic sympathetic neurons

The adrenal medulla does not have?

axons or dendrites

In response to nerve signals, what does the adrenal medulla secrete?

epinephrine and norepinephrine (Catecholamines)

How many hormones does the adrenal cortex produce?

25

What type of hormones does the adrenal cortex produce?

corticosteroid

How many hormones stimulated by the adrenal cortex are physiologically important?

5

All corticosteroid hormones produced in the adrenal cortex are all from?

cholesterol

What are the three categories of hormones in adrenal cortex?

Mineralocorticoids (M), Glucocorticoids (G), and Sex steroids (S)

What do mineralocorticoids in the adrenal cortex do?

regulate electrolyte imbalance

What do glucocorticoids in the adrenal cortex do?

regulate use of glucose and other fuels

What do sex steroids in the adrenal cortex do?

regulate some reproductive functions

What are the 3 zones in the adrenal cortex?

glomerulosa, fasiculata, and reticularis

What makes up 98% of the pancreas?

exocrine tissue

What does the pancreas make?

digestive enzymes

What are the thousands of cells found in the pancreas?

islet cells

The islet cells form what in the pancreas?

Islets of Langerhans

What do the islet cells in the pancreas secrete?

many hormones

Beta cells make up what percent of the pancreas?

70%

Alpha cells make up what percent of the pancreas?

20%

Delta cells make up what percent of the pancreas?

5%

Beta cells in the pancreas secrete what?

insulin

Alpha cells in the pancreas secrete what?

glucagon

Delta cells in the pancreas secrete what?

somatostatin

What does insulin in the beta cells of the pancreas stimulate cells to do?

take up glucose and store it as fat and glycogen immediately after a meal

What does glucagon in the alpha cells of the pancreas do?

stimulates glycogenolysis and gluconegoenesis

Glycogenolysis means?

fat break down

Gluconegoenesis means?

release of glucose between meals

Somastotatin in delta cells of the pancreas inhibit?

alpha and beta cells and digestion

What do the PP and G cells of the pancreas do?

moderate digestive functions

The gonads are what two systems?

endocrine and exocrine

Exocrine secretions of the gonads are?

eggs or sperm (cytogenic)

Endocrine secretions of the gonads are?

steroid sex hormones

What does the theca of the ovaries make?

pre-estradiol

What do the theca and granulosa convert pre-estradiol to?

estradiol

What forms from a ruptured follicle in the ovaries?

corpus luteum

The corpus luteum in the ovaries produces what hormone?

progesterone

What is secreted from both the follicle and corpus luteum of the ovaries?

inhibin

What does inhibin inhibit in the ovaries?

FSH secretion by negative feedback of the anterior pituitary