Endocrine System: Principles of Chemical Communication Flashcards
Secretion
The controlled release of chemicals from a cell
Autocrine chemical messengers & example
Chemical messenger that stimulates the cell that originally secreted it
Ex: White blood cells that stimulate their own replication
Paracrine chemical messengers & example
CMs that act locally on neighboring cells
Ex: histamine, released by white bloodcells during an allergic reaction, which stimulates vasodilation in blood vessels near by
Neurotransmitters
Chemcial messengers secreted by neurons into a synaptic cleft
Endocrine chemical messengers
CMs secreted into bloodstream by certain glands and cells. CMs travel through the general circulation to their target cell
Target tissue / effector
The destination for horomones that are secreted in to the bloodstream
Exocrine glands
DIFFERENT than endocine glands.
Ducts that carry their secretions to teh outside of the body, like saliva, breast milk, etc.
Nervous system v. Endocrine System
Text v. Tweets
Neuropeptide
Neurons that secrete hormones > the neuron’s chem messenger enters the bloodstream, where it functions as a hormone.
Differences in nervous and endocrine system: mode of transport
Endocrine > hormones secreted in to bloodstream
Nervous > neurotransmitters released directly on to target cells
Differences in nervous and endocrine system: speed
Endocrine > more slow
Nervous > fast
Differences in nervous and endocrine system: Duration of response
Endocrine >Longer lasting effects, since hormones remain in the bloodstream
Nervous > activates targets quickly, and only for as long as action potentials are sent
Amplitude-modulated signals
Associated with endocrine system
Total amount of signal produced and the fluctuations in concentration of signal over time
Frequency-modulated signlas
Associated with nervous system
How often a signal is sent in a certain period of time