Endocrine System Flashcards
What brings in homeostasis?
Endocrine system and the nervous system
What methods does the endocrine and nervous system use?
communication that affect specific target organs
EXOcrine glands are….
secretions released into ducts opening onto an epithelial surface
ENDOcrine glands are…
ductless organs that secrete their molecules directly into the bloodstream
What happens if an organ lacks a SPECIFIC receptor?
It does NOT respond to its stimulating effects
Peptide hormones
formed from chains of amino acids
most of our body’s hormones are peptide hormones
ex: growth hormone
What are longer chains of peptide hormones called?
Protein hormone
Steroid hormones
type of lipid derived from cholesterol
ex: testosterone
Biogenic amines
small molecules produced by altering the structure of a specific amino acid
ex: thyroid hormone
What is negative feedback loop?
A stimulus starts a process, and eventually the hormone secreted or a product of its effects causes the process to slow down or turn off
What is an example of negative feedback loop?
regulation of the blood glucose level
Positive feedback loop
Accelerates the original process, either to ensure that the pathway continues to run or to speed up its activities
What is an example of positive feedback loop?
milk release from mom’s boobies
Master Control Center of endocrine
hypothalamus
Hormone in the hypothalamus…
secrete hormones that influence the secretory activity of the anterior pituitary gland
Regulatory hormones
secreted into the blood to regulate secretion of most anterior pituitary hormones
Hypothalamus has _______ over these endocrine organs
Indirect control
What two hormones are transported into the posterior pituitary?
oxytocin antidiuretic hormone (ADH)
Pituitary Gland (Hypophysis)
Small, slightly oval gland housed within the hypophyseal
Covered superiorly by the diaphragma sellae
Connected to the hypothalamus by a thin stalk, the infundibulum.
Partitioned both structurally and functionally into an anterior pituitary and a posterior pituitary
What is the pituitary gland controlled by?
regulatory hormones secreted by the hypothalamus
How do hormones reach the anterior pituitary?
via hypothalamo- hypophyseal portal system
What is hypothalamo-hypophyseal portal system?
“shunt” that takes blood carrying regulatory hormones from the hypothalamus directly to the anterior pituitary