Endocrine Physiology Introduction Flashcards
What are the two major control systems of the body?
Endocrine and nervous systems
Complete the table:
What is the term for a chemical substance released in small quantities from certain glands (endocrine glands) that travels through the circulatory system to elicit a typical physiological response in other cells and tissues, called target cells and target tissues.
Does this include “neurohormones”
Does it include CO2 and intracellular second messengers like cyclic AMP?
Hormones
Yes
Does not include CO2 or cyclic AMP
What are ductless glands that secrete into ECF and then to blood?
Endocrine glands
In the neuroendocrine system, what is secretion of some hormones controlled by? What are three examples?
What are some hormomes that exert some control on nervous system activity?
Nervous system:
Epinephrine
Post pit (OT and ADH)
Sex behavior and Epi (increases anxiety and fear)
What are the three general categories of hormones?
Steroids and steroid-like hormones
Amino acid derivatives (catecholamines and thyroid hormones)
Peptides and proteins
What are the six classifications of steroid hormones?
Andogens
Estrogens
Progestagens
Mineralcorticoids
Glucocorticoids
Steroid-like vitamin D
What are all steroids derived from?
What type of steroid (C-___?) is each?
Progesterone
Testosterone
Estradiol
C-21
C-19
C-18
What is “direct” hormone action?
You can observe the effects of hormone after body/tissues/cells are exposed to it (can still be slow in onset and my end quickly)
Why might indirect effects not be readily observed?
4 reasons
- Hormone might affect another endocrine organ and alter the organ’s hormone secretion
- Hormone might have “permissive action” on target tissue (nothing observable but allows other hormones or changes in metabolites to be more effective.
- Redundancy = several hormones work together to have same effect
- Opposition = opposing hormone effects
BOTH MUST STILL HAVE RECEPTORS FOR IT ON TARGET TISSUE !
Example of a permissive effect? NE or Ep + what to cause large amounts of FA release?
Thyroid hormone
What are two ways a cell can modify its response?
- More high affinity receptors
- Fewer high affinity receptors
Change the sensitivity/ change the response capacity
What is teh effect of “spare receptors” on the biological response?
What are the two major functions of second messengers?
- Amplify signal of hormone receptor binding
- Dispense signal to several other processes
When is the second messenger formed? What is the cAMP pathway?
Two major functions of second messenger system?
- Amplify signal
- Disperse signal to many places in the cell
What are the two methods of hormone transport?
What is the totlal hormone concentration in plasma?
What are the active form of hormones on target cells and on feedback sensors?
If binding protein is increased, what is the effect on levels of free hormone?
Define each:
Circadian rhythm:
Ultradian rhythm:
Other two episodic secretions?
ACTH and cortisol secretion have circadian rhythm
What should you think about when sampling hormone?
Changes in work or sleep patterns
What are two circadian rhythm hormones?
What is a pulsatile hormone example (ultraridian, multiple times per day)?
What is a stimulus induced hormone?
ACTH, cortisol, testosterone
LH
Prolactin
What are three ways that blood levels of hormone can be altered? Which one is the major way?
What is often due to over or under production of a hormone?
Draw the general pathway for DIRECT hormonal effects.
Draw the two endocrine gland pathways
Draw the three glands pathways
What is postive feedback?
What is an example?
