Endocrine System Overview Flashcards
What structures does the endocrine system consist of?
Glands and other structures that produce hormones
Examples of glands and structures that are part of the endocrine system - ENDOCRINE GLANDS
Endocrine Glands
pituitary
pineal
thyroid
parathyroids
adrenals
Examples of glands and structures that are part of the endocrine system - GLANDS WITH PARTIAL ENDOCRINE FUNCTION
Glands with partial endocrine function
thymus
pancreas
liver
Examples of glands and structures that are part of the endocrine system - NON-GLANDULAR STRUCTURES THAT PRODUCE HORMONES
Non-glandular structures that produce hormones
hypothalamus
skin
heart
stomach
kidneys
small intestine
gonads
placenta
What functions does the endocrine system serve in the body?
CONTROLS BODY ACTIVITIES - by chemical messengers known as hormones
What is the other principle control system of the body?
THE NERVOUS SYSTEM - by way of nerve impulses
Nervous Vs Endocrine
Chemical Messengers:
Distance over which messengers have action:
Type of system:
Speed of response:
Time to terminate a response:
Target organ:
NERVOUS SYSTEM
neorotransmitters
very small (synapses)
wired
very fast (milliseconds)
primarily muscles and glands
ENDOCRINE SYSTEM
hormones
may be small or large (via blood)
wireless
slower (seconds or minutes)
most body organs
All glands of the body are a subtype of which of the four basic types of tissue?
EPITHELIAL TISSUE (glandular epithelium)
What are some differences between endocrine and exocrine glands?
EXOCRINE secrete their products by way of DUCTS that lead to the SURFACE OF THE BODY OR SOME INTERNAL CAVICTY, such as the lumen of the digestive tract
ENDOCRINE glands DO NOT HAVE DUCTS. They secrete their products (hormones) into the intestinal fluid around the secretory cells, and then the products diffuse INTO THE BLOOD to be carried to their target cells
Some glads that are considered EXOCRINE
Sebaceous (oil)
Sudoriferous (sweat)
Mammary
Prostate
What determines which hormones affect which target cells?
Hormones affect their target cells that have receptors for that specific hormone
Local hormones
hormones that are NOT RELEASED INTO THE BLOOD but act on neighboring cells within the tissues they are released
Local hormones that affect neighboring cells may be referred to as
PARACRINES
Local hormones that affect the same cells that secrete them may be known as
AUTOCERINES
Two broad types of hormones:
lipid-soluble
water-soluble
Know specific lipid-soluble and water-soluble hormones?
slide 10
Receptors for lipid-soluble hormones are located:
WITHINB THE CYTOSOL OR NUCLEUS OF THE TARGET CELL
RECEPTORS FOR MOST WATER-SOLUBLE HORMONES ARE LOCATED:
ON THE SURFACE OF THE TARGET CELL
Mechanisms for controlling blood levels of hormones
FEEDBACK CONTROL
most hormones controlled by feedback mechanisms follow
NEGATIVE FEEDBACK
the production of hormone does the opposite of blood level
example: if blood levels rise, the glad produces less hormone
few hormones controlled by feedback mechanisms follow
POSITIVE FEEDBACK loops
output parallels with input
used to move from equilibruim
NERVOUS SYSTEM CONTROL influences the release of many hormones.
Which part of the nervous system would be involved?
HYPOTHALAMUS
AUTONOMIC DIVISIONS
daylight influencing the release of hormones is an example of
EXTERNAL CUES AND RHYTHMS that affect hormone levels in the blood
