Endocrine Flashcards
Endocrine derived from the greek words
endo - within
krino - secrete
Composed of endocrine glands and specialized endocrine cells located throughout the body.
Endocrine system
Endocrine glands secrete chemical messengers called “____” into the bloodstream in order to produce a specific response to ____
hormones
target tissues or effectors.
Hormones derived from the Greek word
Hormon - to set in motion
hormones has two chemical categories
- Lipid- soluble
- Water-soluble
• Non-polar
• Small size and low solubility
in aqueous fluids.
Lipid- soluble hormones
• Polar
• Vary from small to large and
soluble in blood
Water-soluble hormones
Receptor Location: Nucleus or cytoplasm
Lipid-soluble hormones
• ReceptorLocation:Plasma membrane’s outer surface
Water-soluble hormones
Needs a binding protein for transport
Lipid-soluble hormones
dissolvedirectly into the blood and are delivered to the target tissue without attaching to binding protein.
Large hormones
need attachment to larger protein to avoid being filtered out of the blood.
Small hormones
There are three types of stimuli which regulate hormone release
- Humoral 2. Neural
- Hormonal
Blood-borne chemicals which stimulate release of some hormones are called
humoral stimuli
It occurs when a secreted hormone stimulates the secretion of other hormones. These hormones are called
Tropic hormones
There are hormones that prevents the secretion of other hormones. These hormones are called
“inhibiting hormones.”
Hormone release caused by altered levels of certain critical ions or nutrients.
Humoral stimulus
Hormone release caused by neural input.
Nueral stimulus
Hormone release caused by another hormone (a tropic hormone).
Hormonal stimulus
consists of ductless glands
Endocrine system
The following are the endocrine glands and organs:
- Pituitary gland
- Thyroid gland
- Parathyroid gland
- Adrenal glands
- Pancreas
- Testes and Ovaries
- Thymus
- Pineal Gland
The pituitary gland is also called the
Hypophysis
It is a small gland about the size of a pea.
Pituitary gland
It rest in a depression of the sphenoid bone inferior to the hypothalamus of the brain.
Pituitary gland
attached to the hypothalamus by this structure.
Infudibulum
2 parts of pituitary gland
• Anterior pituitary • Posterior pituitary
The thyroid gland is made up of two lobes connected by a narrow band called
Isthmus
One of the largest endocrine glands.
Thyroid gland
Appears more red than surrounding tissues.
Thyroid Gland
Main function: Secretion of thyroid hormones
Thyroid Gland
are synthesized and stored within the thyroid follicles.
Thyroid hormones
thyroid follicles contain protein called “_____” in which hormones are attached.
thyroglobulin