Chapter 18 - The Endocrine System Flashcards
The endocrine system acts with what other system to control all body systems?
Nervous system
Compared to the nervous system, the endocrine takes longer to? The effects, however, last _______ and influence what?
Cause a response / longer, a broader area of the body
The endocrine system releases these chemical substances that enter the bloodstream and travel to target cells where they exert effects by binding to receptor sites.
Hormones
The endocrine system consists of these ductless glands that release hormones.
Endocrine glands
The endocrine system consists of? (2)
Endocrine glands & several other organs and tissues that contains cells that secrete hormones.
Name the endocrine glands (5)
Pituitary, pineal, thyroid, parathyroid, adrenal glands
Glands that are not classified as endocrine glands, but they still secrete hormones (13)
Hypothalamus, ovaries, testes, kidneys, stomach, liver, pancreas, small intestine, thymus, heart, skin, adipose tissue, placenta
Hormones help to regulate? (5)
CHEMICAL composition and VOLUME of body fluids, metabolism and energy BALANCE, CONTRACTION of smooth and cardiac muscle fibers, SECRETION of glands, some IMMUNE system activities
Name 3 functions of hormones.
CONTROL growth and development, REGULATE operation of the reproductive system, help establish CIRCADIAN rhythms
How do hormones influence their target cells?
By binding to their receptors (typically protein)
Most target cells have how many receptors for a specific hormone?
2,000 - 100,000
If a hormone is prevented from binding with a receptor, what happens?
It cannot carry out its normal function.
What eventually happens to most hormones?
They are inactivated by the liver and excreted by the kidneys.
Most of these types of hormones are attached to transport proteins which make the hormones water-soluble long enough to circulate to the target cells.
Lipid-soluble hormones
Where are the receptors for lipid-soluble hormones located?
Inside of the target cells
These types of hormones circulate freely in the blood plasma.
Water-soluble
Example of a water soluble hormone.
Insulin
Where are receptors for water-soluble hormones located?
In the plasma membrane of target cells
Hormone secretion is regulated by what 3 things?
SIGNALS from the nervous system, CHEMICAL CHANGES in the blood, OTHER hormones
What is the main link between the nervous and endocrine systems?
The hypothalamus
What is the master endocrine gland?
The pituitary gland
What is the pituitary gland attached to?
The hypothalamus
The pituitary gland secretes hormones that do what?
Regulate other endocrine glands.
The pituitary gland consists of two of these? They are called?
Lobes / a large anterior and smaller posterior