Endocrine System (copy)

Endocrine Gland

Endocrine Gland

Structure in the body that specializes in producing a compound released directly into blood stream

Hormone

The substance being released into blood stream

Target Cell / Tissue / Organ

Cells with receptors to specific hormones

Peptide hormones

Bind to specific receptors on the target cell’s plasma membrane

Steroid hormones

Pass through the plasma membrane into the cell and bind to receptors inside the cytoplasm

Steroid/receptor complex

Generally acts on RNA transcription and protein production

2 nd messenger system

cAMP, Ca++, enzymes, nucleotides or lipids

Control

occurs by feedback mechanisms and most commonly negative feedback

Antagonistic Hormones

Cause the opposite action from each other is common

Insulin and Glucagon

control of glucose levels

Pituitary Gland

What is the Thyroid Gland and Thyroxin production controlled by

temperature and tell the pituitary to produce Thyroid Stimulating Hormone, TSH, controlling Thyroxin production

What do sensors in the hypothalamus monitor

Thyroxin production is stepped up in the thyroid gland, which increases metabolism and produces heat

What happens if body temperature drops

Thyroxin production decreases and slows down the metabolism

What happens if body temperature rises

Sensors in Hypothalamus

What monitors water level of blood

Less water

causes the Hypothalamus to tell the pituitary to produce ADH, Anti-Diuretic Hormone

Anti-Diuretic Hormone

causes thirst and conserves water by acting on kidneys

Kidney functions

conserve water by producing a more concentrated urine

More water

causes ADH to be produced less, thus conserving less water by forming a more dilute urine, (containing more water).

Hypothalamus

-Produces hormones that control (and are stored in) the pituitary gland

hypophyseal portal system

Produces ADH and Oxytocin which are stored in the posterior pituitary and hormones from hypothalamus travel

Oxytocin function

stimulates uterine contraction

Pituitary Gland

Produces 8 hormones that control other glands

Posterior pituitary

an extension of the axons from the hypothalamus Produce Releasing and Inhibiting Hormones to control Anterior Pituitary. Store Anti-Diuretic Hormone and Oxytocin

Anterior Pituitary

controlled by the hypothalamus but makes its own hormones. -Many control other glands / tissues / organs

Prolactin

Mammary glands. Stimulates breast development and milk production. Has been found to play roles in many other areas of the body from reproductive, metabolic, behavior and the immune system.

Growth Hormone

Bone, muscle, adipose tissue. Primary effect is to stimulate protein synthesis, speed up the the cell cycle and growth of tissue / body.

Follicle Stimulating Hormone

Testicles and Ovaries. Stimulates growth, development, and puberty

AdrenoCorticoTropic Hormone

Produced in response to stress and stimulates the production of cortisol by the adrenal glands

Thyroid Stimulating Hormone

Stimulates the release of thyroxin by the thyroid gland

AntiDiuretic Hormone

Acts on the kidneys’ reabsorption of water

Oxytocin hormone

Mammary Glands and Uterus. Plays a role in sexual development and milk production. sometimes referred to as the “love hormone” for pro-social behavioral action.

Luteinizing Hormone

Testicles and Ovaries.In females an acute LH “surge” causes ovulation. -In males, LH stimulates the production of testosterone

Pineal Gland

Produces Melatonin and Serotonin which are involved in circadian cycle (sleep / wake). Has wide-ranging effects on heart rate / blood pressure, alertness, body temperature, and muscular system

Thyroid Gland

Found in the neck. -Release thyroxin, T4 , which is converted to triiodothyronine, T3 , which increases metabolism

Thyroxin

made from the amino acid tyrosine and iodine. -Effects almost every cell's metabolism

Calcitonin

causes a decrease in blood calcium by increasing bone growth and decreasing absorption by intestines and kidneys

PTH

Hormone which raises calcium levels in blood. Increases conservation of calcium by kidneys, increased absorption by intestines, and increased osteoclast degradation of bone

Parathyroid

4 glands found around thyroid gland, Hormone which raises calcium levels in blood

Thymus

Found above and around the heart. -Produce Thymosin which stimulates T-cell “maturation” in the immune system.

Pancreas

Found in the abdominal cavity. Both an endocrine and exocrine gland. Also produces digestive juices into the small intestine

Alpha cells

produce glucagon

Beta cells

produce insulin

Diabetes mellitus

Body does not produce insulin or enough insulin

Type-1 Diabetes

In children, body produces little or none. Get insulin injections

Type-2 Diabetes

In adults, low to normal levels produced but cells don’t respond to insulin. Monitor diet better

insulin

STORES glucose AS glycogen in liver and muscles

glucagon

RELEASES glucose FROM glycogen in liver and muscle

triiodothyronine, T3

increases metabolism