Chapter 17 : Endocrine System Flashcards
Endocrine system
Uses glands, tissues, and cells to produce molecules called hormones
These hormones will control the bodies metabolism, growth and development
Endocrinology
The study of the endocrine system and the diagnosis and treatment of its disorders
Endocrine glands
An organ that produces the hormone
Hormones
Chemical messengers that are transported by the bloodstream and stimulate physiological responses in cells of another tissue or organ, often a considerable distance away
Overview of cell communications
Internal communication is necessary for coordination of cell activities
There are 4 principle mechanisms of communication between cells
- gap junctions, neurotransmitters, paracrine hormones, and hormones
Gap junctions
Pores in cell membrane allow signaling molecules, nutrients, and electrolytes to move from cell to cell
Paracrine ( local ) hormones
Secreted into tissue fluids to affect nearby cells
What is this organ from the endocrine system?
Pineal gland
What is this organ from the endocrine system?
Hypothalamus
What is this organ from the endocrine system?
Pituitary gland
What is this organ from the endocrine system?
Thyroid gland
What is this organ from the endocrine system?
Thymus
What is this organ from the endocrine system?
Adrenal gland
What is this organ from the endocrine system?
Pancreas
What is this organ from the endocrine system?
Parathyroid glands
What is this organ from the endocrine system?
Gonads: ovary (female)
What is this organ from the endocrine system?
Gonads: testis (male)
Communication by the endocrine system compared to the nervous system
Response take longer before they begin and last longer
Works with the nervous system via the adrenal gland and pituitary gland
Communication of the endocrine system
Body tells endocrine gland to release its hormones into a capillary bed
They travel around the body until they reach the target cells
Target cell then does what it was told to do by that hormone
Target cells
A Cell that has a receptor for that specific hormone
Anterior pituitary gland
Controlled by hormones from the hypothalamus via a portal system
Far more vascularized (darker color)
More cellular
Portal system
2 subsequent capillary beds
Posterior pituitary gland
Hypothalamus has neurons that travel to the posterior pituitary gland
Less cellular and has many nerve fibers  (has lighter stain)
Hypophyseal portal system: hypothalamic hormones
Hypothalamic releasing and inhibiting hormones travel in hypophyseal portal system from hypothalamus to anterior pituitary gland
Hypophyseal portal system: anterior lobe hormones
Hormones secreted by anterior pituitary gland
Chromophobe
In the anterior pituitary gland
Don’t stain very dark
Chromo-color
Phobe/phobia-aversion to something/don’t like it
Acidophil
Darker stain
TRH
Thyroid releasing hormone
Tells anterior pituitary gland to direct hormones to the thyroid
Releasing hormones
The hormones the hypothalamus makes to direct the pituitary gland to release hormones
GnRH
Gonad releasing hormone
Tells anterior pituitary gland to direct hormones to the gonads
CRH
Corticotropin releasing hormone
Directs anterior pituitary gland to direct hormone to adrenal gland
GHRH
Growth hormone releasing hormone
Directs anterior pituitary gland to produce growth hormone
PRL
Prolactin
Anterior pituitary gland produces it
Tells mammary gland to begin producing lactin
After birth stimulates mammary glands to synthesize milk, enhances secretion of testosterone by testes
TSH
Thyroid stimulating hormone
Produced by the anterior pituitary gland
Stimulates secretion of thyroid hormone
LH
Luteinizing hormone
Produces by anterior pituitary gland
Direct gonads
Stimulates ovulation, corpus luteum to secret progesterone, and stimulates testes to secret testosterone
FSH
Follicle stimulating hormone
Produced by anterior pituitary gland
Directs gonads
Stimulates secretion of ovarian sex hormones, development of ovarian follicles, and sperm production
GH
Growth hormone
Produced by anterior pituitary gland
Active most importantly on liver and muscle cells
Stimulates mitosis and cellular differentiation
ACTH
Adrenocorticotropin hormone
Produced by anterior pituitary gland
Works on the adrenal cortex to secret glucocorticoids