animal responses Flashcards
what are the two main response systems in animals
nervous and endocrine
function of glial cells
support and maintain neurons
afferent neurons
conduct the signal towards the integrating center (e.g. brain or ganglia)
interneurons
- in the brain or ganglia
- coordinate signals
efferent neurons
conduct signals out to effector organs such as muscles and glands
what is the resting membrane potential
-70 mV
graded potentials
- occur in dendrites and cell body
- only travel short distances
- vary in magnitude
action potentials
- occur in axons
- all or none
- can be ‘regenerated’ so can be conducted across long distances
synaptic potentials
cause neurotransmitter release
gentle pressure causes ___ frequency of action potentials per receptor
low
greater pressure causes ___ frequency of action potentials per receptor
high
central nervous system
brain and spinal cord
peripheral nervous system
lies outside of the brain and spinal cord
in both plants and animals, the inside of the cell is more negative/positive than the outside
negative
what sets up the concentration gradients
sodium-potassium pump / Na+/K+ ATPase
spatial summation
graded potentials originating at different locations can influence the net change in membrane potential
absolute refractory period
- inactivation gate closed
- no new AP is possible
relative refractory period
- inactivation gate open
- new AP possible but less likely bc neuron is hyperpolarized
myelin
- formed by schwann cells wrapped around the axon
- insulates the axon
saltatory conduction
apparent “leaping” of action potential from node to node
