Chapter 11 Anatomy & Physiology

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Chapter 11

Intro:

endocrine system

cells, tissues, organs: secret hormones into body fluids

exocrine

SECRETES products into ducts

endocrine

SECRETES products into the body fluids into the affected target cells

general characteristics of the system:

communicate with cells using chemicals called HORMONES

regulate metabolic processes within the cells & the whole body

only affect the specific target cells

pituitary gland

thyroid gland

parathyroid glands

adrenal glands

pancreas

other hormone-secreting glands and tissues

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Hormone Action

hormones = steroids

amines

peptides

proteins

glycoproteins

can influence target cells even they are present

Steroid Hormones

lipid-soluble & can pass through cell membranes

receptors for SH's are located in the target cell's NUCLEUS

blinds with DNAnd activates specific genes that direct the synthesis of specific proteins

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nonsteroid hormones

combine receptors in target cell membranes & have a binding and activity site

the hormone receptor complex triggers a cascade of biological activity

Prostalandins

locally made lipids that affect the organ in which they are made

relax smooth muscle, contract smooth muscle, simulate the secretion of other hormones, influence blood pressure & inflammation