Endrocrine System

Front 1

How do hormones reach almost all body cells?
How do they produce their effects?
Removal of hormone...

Back 1

Via blood stream.
produce their effects only in "target" cells that have receptors for the hormones.
Freely circulating hormones are rapidly removed from blood stream and those attached to transport protein are removed slowly.

Front 2

Name the three types of hormones and give examples of each.

Back 2

Amines (Amino Acid derivatives) thyroid hormones, epinephrine and norepinephrine...
Peptides (Amino Acid Chains) Insulin, glucagon, GH....
Lipid Derivatives: steriods and eicosanoids (prostaglandins...)

Front 3

Which hormones cannot cross cell membrane directly?

Back 3

Amines, peptides, and eicosanoids. They produce their effect via G protein/2nd messenger (cAMP or Ca ion)

Front 4

Which hormones cross plasma membrane directly?

Back 4

Thyroid and steroid hormones, and produce their effects by controlling gene expression and ATP synthesis.

Front 5

When the hypothalamus neurons release regulatory hormones in the adenohypophysis portion where do the hormones go?

Back 5

They are released in fenestrated capillaries of the hypophyseal portal system. The blood that enters the portal system will go to its intended target cells before returning to the general circulation.

Front 6

TSH: What does it trigger the release of? What hormone promotes the release of TSH?

Back 6

Triggers the release of hormones from thyroid gland.
TRH promotes the release of TSH

Front 7

Adrenocorticotropic: What does it trigger? What causes the secreation?

Back 7

Stimulates the release of steroid hormones (Glucocorticoids)from the adrenal cortex.
CRH causes the secreations of ATCH.

Front 8

FSH: What does it stimulate in males and women? What hormone promotes this secreation?

Back 8

Males: sperm production in sustentacular cells of testes.
Females: follicle development (egg maturation) and estrogen secretion in ovaries.
GnRH

Front 9

LH: What does it cause? What hormone promotes this secreation?

Back 9

Ovulation and progestin porduction in ovaries. In males androgens production in testes.
GnRH

Front 10

PRL: What does it stimulate?

Back 10

Stimulates the development of mammary glands and milk production.

Front 11

MSH: What does it stimulate? And how is it produced?

Back 11

Melanocytes to produce melanin pigment in skin and other locations.
In humans, MSH is produced locally and within exposed skin.

Front 12

GH: What does it cause? What is its direct effect?

Back 12

Release of somatomedins(cause increase in amino acid uptake in skeletal muscle cells, cartilage cells-stimulates protein synthesis and cell growth) from liver.
Direct effect is that it increases cell division in epithelial and connective tissues, enhance break down of lipd and glycogen energy reserves.

Front 13

What are the two hormones released from the thyroid gland?

Back 13

Calcitonin (C cells) released in response to high Ca levels (inhibits osteaclasts)
Thyroid hormone (follicle cells) thryoxine and triiodothyronine.

Front 14

What are thyroid hormones and what are their functions?

Back 14

Amino acids with attached iodide ions and are attached to transport proteins in the bloodstream.
Produce strong, immediate, short-lasting increase in the rate of cellular metabolism and use of energy. Bind to intercellular receptors (mitochondria and receptors in nucleus to activate genes that control energy utilization).

Front 15

When in parathyroid hormone secreted?

Back 15

When there is lower than normal calcium concentrations (it stimulates osteoclasts, inhibits osteoblasts, decrease Ca excretion by kidneys, and stimulate formation of calcitriol by kidneys.

Front 16

What does calcitriol do?

Back 16

Calcitriol is involved in the digestive tract and absorption of Ca ion (regulates and acts on digestive tract. (PTH and Calcitonin opposing effects)

Front 17

What are the functions of the hormones from the Adrenal medulla?

Back 17

Produce increased availability of energy resources (glycogen to glucose for brain in liver and fat to release fatty acids for use)
Produce increased rate and force of cardiac contractions and other sympathetic effect.
Controlled by AND activity.

Front 18

When is mineralcorticoids secreted?

Back 18

When Na+ is low, K+ is high, bp is low (causes retention of NA+ and water, loss of K+

Front 19

Why are glucocorticoids secreted?

Back 19

In response to ACTH release from anterior pituitary (causes decrease use of flucose and increased rate of glycogen sythesis and has anti-inflammatory effects)

Front 20

What are the roles of androgens?

Back 20

Encourages bone and muscle growth, blood formation (primary role is in children and women, tested of adult makes produces larger amounts)

Front 21

Which of the following would be expected in a case of tumor that causes hyper-parathyroidism?

Back 21

Levels of PTH would be elevated, CA ion concentrations in blood would be abnormally high, bones would become weakened due to loss of CA

Front 22

Which of the following endocrine glands are composed of neural cells?

Back 22

Post. Pituitary gland and adrenal medulla.

Front 23

What are some possible functions of melatonin?

Back 23

Setting cardian rythms, anti-oxidant protecting against damage by free radicals and inhibiting reproductive function