Endocrine system

Hormones

Chemicals released by glands of the E.S. into the blood stream.

Hormones regulate many bodily functions by sending messages to cells.

Non-steriod and steroid hormones

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Steroid hormones

Hormone-receptor complex

Nucleus

DNA

mRNA

Protein synthesis

Altered cellular function

ReceptorSteroid hormone

Regulate a cell’s DNAby turning genes on or off

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Non steroid hormones

These messengers activate and inhibit many cell activities.

ATP cAMP (second messenger)

Enzyme activities

Altered cellular function

Can’t enter the cell, but use secondary messengers to alter cell functions

Homeostasis

Metabolism: internal body heat adjusts to temperature.

Water balance: causes thirst if too low, extra urine output if too high.

Master glands

Pituitary: controls 9 other glands Produces growth hormone Hypothalamus: part of the nervous sys. that

controls the pituitary.

Thyroid gland: regulates the body’s metabolism- rate at which cells use energy

Parathyroid: controls the Calcium balance in the blood.

Adrenals

Located on top of each kidney

Forms adrenaline as a reaction to stress:

faster heart beat, stronger, more alert

“fight or flight” response

Pancreas

Regulates levels of blood sugar in cells. Insulin allows cells to take in glucose.

Diabetes mellitus: disease of the pancreas where insulin is not produced or used properly.

Comparing type I, type II diabetes

Type I Diabetes

Gonads Function: production of gametes and

secretion of sex hormones. Controls male and female sexual

reproduction.