Ex Phys Chapter 3 Flashcards
Which system Regulates all functions within the human body
Nervous system
Wiring through whole body: impulse sent to & received from all tissues of the body is which system
nervous system
The _____
- Integrates incoming information
- Selects an appropriate response
- Signals the involved organ and tissues to take appropriate action
Brain (central computer)
The nervous system is in charge of
Communication, coordination, interaction of tissues and systems in the body
The more divisions of the nervous system are
Central Nervous system, peripheral nervous system
The central nervous system is made up of the: _____ & ____
brain and spinal cord
The peripheral nervous system consists of _____ and _____
Sensory (afferent)
Motor (efferent/effector)
Sensory (afferent) is in charge of ____ signals
incoming
the motor (efferent/effector) is in charge of _____ signals
outgoing
The motor neurons are broken up into the sections ____ and _____
Somatic & autonomic
characteristics of Somatic neurons are they’re _____ and connected to _______ muscles
voluntary & skeletal muscles
Characteristics of Autonomic neurons are they’re ____ and connected to ______
involuntary, and connected to visceral organs
Basic structural unit of nervous system
neuron
Has same basic structure everywhere in body
neuron
Has three major regions
Cell body (soma)
Dendrites
Axon
Neuron
- Contains nucleus
- Cell processes radiate out: dendrites & axon
neuron cell body
_____ receives cell processes and carry impulse toward cell body
dendrites
- Sender cell process, starts at axon hillock
- End branches, axon terminals, neurotransmitters
Axon
The function of the nervous system:
- Electrical signal for communication between _____ and _____
- Must be generated by a _____
- Must be propagated down an ____
- Must be transmitted to next ____in line
- periphery and brain
- stimulus
- Axon
- cell
_____ are referred to as excitable tissues: responding to stimuli, converting it to an electrical signal (nerve impulse)
Neurons
resting membrane potential is the
Difference in electrical charges between outside and inside of cell
depolarization occurs
when inside of the cell becomes less negative -70 mV -> 0 Mv
During depolarization the inside of neurons become less negative when more ___ channels open up, and ___ enters cell
Na+ & Na+
______occurs when inside of cell becomes more negative. –70 mV → −90 mV
Hyperpolarization
During hyperp;arization More ___ channels open, __ leaves cell
K+ & K+
Depolarization and hyper polarization contribute to nervous system function via _____ potentials & _____ potentials
graded potentials and action potentials
Graded potential helps body decide whether to pass signal to ____ and excite or inhibit a _____
axon, neuron
action potential passed signal down _____ and is only excitatory
axon
action potential begins as
graded potential
if graded potential reaches -_____ mv action potential will occur
-55
Threshold mV not reached = no action potential is part of the ____ or ______ principle
all or nothing principle
this period of action potential occurs during depolarization, the neuron is currently unable to respond to another stimulus, and Na+ channels are already open and can’t open more.
Absolute refractory period
This period of action potential occurs during the depolarization stage. Neurons respond only to very strong stimulus during this period. K+ channels open and (Na+ channels are closed, and could open again)
relative refractory period
___ speeds up propagation
myelin
Fatty sheath around axon
(Schwann cells)
when the axon diameter is larger, it’s ____
faster
the junction of gap between neurons is the site of ____ to ___ communication
neuron to neuron
Action potential potential can only move in one ____
direction
Axon terminals contain
neurotransmitters
the two major categories of Neurotransmitters are
- Small molecule, _____ acting
- Large molecule neuropeptides, slow acting
rapid, slow
ACh stimulates _____ muscle contraction, mediates parasympathetic nervous system effects
skeletal
