Biology Flashcards
cells
the basic structural, functional, and biological unit of all known living organisms
neurons
specific specialized cells that send + receive motor messages that tell us to do simple things like walk and blink
dendrites
receive info from other neurons
axons
sends (transmits) impulse to other neurons
glial cells
remove dead neurons and waste products from nervous system
myelin sheath
covers the axon, helps speed communication
all-or-more-principle
neurons fire or they don’t
refractory period
time of recovery where messages from neurons will not fire (recovery is short)
• rests at a 70 charge
synapse
space between neurons
neurotransmitters
the chemical keys to communication
nervous system
two main divisions are the CNS and PNS:
• CNS consists of the brain and spinal cord
• PNS is divided into two categories: the somatic nervous system and autonomic nervous system
somatic nervous system
controls voluntary muscle movements
autonomic nervous system
controls our automatic functions like our heart, lungs, glands, etc
sympathetic system
mobilizes our body to respond to stress
(alert system)
parasympathetic system
shows down the body (brake pedal)