Intro to Endocrine system flashcards
Paracrine signaling
Hormones diffuse short distances to affect neighboring cells
Autocrine signaling
Hormone influences its’ own behavior
Juxtacrine signaling
Involve cell to cell contact
Cytokine signaling
Coodinate immune system response. Signaling molecule must bind and a second messenger is activated to alter enzyme activity.
Permissive hormones
The presence of the hormone at a threshold concentration is required for a second hormone to have an effect
Trophic effects
Promotes growth and health but doesn’t necessarily stimulate release of hormone directly
Diurnal rhythm
Concentration of hormone varies throughout the day
Pulsatile release
Change in concentration over 1-2 hour periods due to presence of clock-like mechanism in the system
How to tell if it is a negative feedback system
If there are an odd # of minus signs in the pathway
Neural systems
Point to point manner of affecting cells, tissues, and organs. Less diffuse and global than other systems. Faster than endocrine mechanisms.
How do cytokines differ from hormones?
Cytokines are produced by a wide variety of cells while hormones are in a specific set of cells in endocrine organs. Cytokines are present in much smaller concentrations than hormones.
