Endocrine System 1 Flashcards
What are the differences between endocrine & nervous system?
The NS uses electrical impulses which provides much faster and briefer responses while the ES uses hormones which provide slower & more sustained responses
What are the functions of the ES?
Affect reproduction, growth, development, conception, metabolism, stress responses & aging
What is the function of endocrine glands?
Release their products directly into the bloodstream without ducts to target cells & thus are highly vascularized
What two components make up the ES?
Endocrine glands & endocrine tissue
What are endocrine glands?
Primary function to produce hormones such as the pituitary, thyroid, PT, adrenal & pineal glands
What are endocrine tissue?
Located in organs that perform other functions such as the pancreas, hypothalamus, gonads
What are hormones?
Chemical messengers released by endocrine glands into the bloodstream to stimulate or regulate specific body cells or functions
How do hormones only affect certain cell despite their wide reach?
Hormones only act on cells that have specific receptors - target cells
How many receptors does each target cell have?
2000-10,000
What is down-regulation?
An excess of hormones can decrease the receptors in target cells and decrease the effect of hormones
What is up-regulation?
A deficiency of hormones can increase the receptors in target, and increase the effects of hormones
What hormone has receptors across the body?
Thyroid hormone
What are the two types of hormones?
Local & circulating (common) hormones
What are circulatory hormones?
Circulating hormones pass from secretory cells to the bloodstream.
What are local hormones?
Affect the secretory cells that released them or neighboring cells without entering the bloodstream.