Chapter 18 Endocrinology Flashcards
What does the Endocrine System do?
Slowly But effectively Maintaining Homeostasis
Where are the hormones released?
The Blood Stream
What are Hormones?
Chemical messengers that are transported in the bloodstream and are two alter the activities of a specific cells in other tissues.
What do all Target cells have?
Specific Receptors.
T/F Target Cells can respond to only one Hormone at a time?
False, They can respond to several at a time.
What are Water soluble Hormones including epi and nor epi classified as?
Amino Acid Derivatives ( Tyrosin)
What is Peptide Hormones composed of?
Amino Acids
What type of Hormone is Insulin?
Peptide
Sex Hormones are what?
Steroids
Charitistics of Steroid Hormones (4)
1) Lipid soluble
2) Similar structure to Cholesterol
3) Binds with intercellular receptors
4) Gene Transcription occurs when binding to receptors s
What is a called when a hormone works with a second messenger?
Catecholamine
What is the second messenger that Epi and Nor-Epi work with?
Cyclic AMP
Hormones that change, Quantities, activities, and identities are called what?
Enzymes
What does the enzyme Kinase Preform?
Phosphorylation
What do G Proteins do?
Connect first and second messengers
What do Calcium ions serve as a second messenger for?
Calmodulin
Why does Cyclic AMp act as the second messenger?
B/c it activates protein Kinases
T/F, Do Catecholamines, Peptide Hormones, and eicosanoids Need a second messenger?
True
T/F, Thyroid hormones and steroids get stopped at the cell membrane?
False
When a catecholamine or peptide hormone bind with a receptor what happens next?
The second messenger appears in the cytoplasm of the cell
What happens when the enzyme adenyl cyclase is activated
cAMP is formed, which means If the adenyl cyclase activity of the liver cells were missing, Glucagon hormones could no longer stimulate the release of insulin
When PDE (phosphodiesterase) is activated, what happens?
cAMP is broken down.
RH (Realising Hormone) and IH (Inhibiting hormone) control the functions of what?
The Anterior Pituitary Gland
Where do Rh and IH are released from where?
The Median Eminence of the Hypothalamus
What organ system is the Hypothalamus involved in?
Neural and Endocrine
What does the hypothalamus control the release of?
Adenhypophysis (anterior pituitary gland) by recreating RH and IH into the hypophysealportal system
If the hypothalamus was damaged no TRH, CRH, GnRH would be released by the hypothalamus, What would happen?
NO TRH- The hypothalamus could not control the Thyroid hormone.
NO CRH- The hypothalamus could no longer control the Cortison
NO GnRH- the hypothalamus would no longer control gonadal Hormones ( sex hormones)
Hormones that control the function of the Posterior Pituitary Gland?
ADH and Oxytocin of the Hypothalamus
What would result if there was the destruction of the Supraoptic nucleus of the hypothalamus
A decrease of ADH
What’s the Main Function of ADH
Decrease the loss of water loss at the Kidneys, This will cause a change of the blood osmotic pressure
Where is the Pituitary gland?
Stella Tarcugia of the Sphenoid bone
What is the posterior portion of the Pituitary Gland called?
Neurohypophysis
Whats the anterior portion of the Pituitary gland called?
Adenohypophysis
What hormones are released from the pituitary gland? (7)
TSH, ACTH, FSH, LH,MSH, GH, AND PRL
Whats the hormone that is released by the pars intermedia of the adenohypophysis during early childhood?
MSH
What hormone may lead to acromegaly if hypersecreted after the closure of the epiphyseal plate?
GH, From the anterior pituary gland
What will happen if there is an excess secretion of GH PRIOR to puberty?
Gigantism
What will occur if there is an excess secretion of GH AFTER puberty?
Acromegaly
What is the hormone Prolactin for?
Milk Production
Whats the hormone Oxytocin for?
Milk Ejection, and promoting Contrations
How does GH Promote bone and muscle growth?
Increasing the Amino acid uptake.
Growth Hormone can also cause what? (diabetic effect)
Hyperglycemia
Liver cells respond to GH by releasing what?
Somatomedins or IGF (insulin-like growth hormones)
Hormones that stimulate endocrine glands to release other hormones are called what?
Tropic hormones
The anterior pituitary hormones that trigger the release of thyroid hormones from the thyroid
TSH