QUESTIONS WITH ACCURATE
ANSWERS 2026/2027 UPDATE.
Nervous System - Answer organ system consisting of the brain, spinal cord, and associated
nerves that coordinate the other organ systems of the body.
The 2 Divisions of the Peripheral Nervous System (PNS) - Answer Somatic and Autonomic
somatic nervous system - Answer nerves that serve the skin, skeletal muscle, and tendons;
voluntary and involuntary control (reflexes)
autonomic nervous system - Answer regulates activity of cardiac and smooth muscles,
organs, and glands; involuntary control
two subdivisions of the autonomic nervous system - Answer sympathetic and
parasympathetic
sympathetic nervous system - Answer promotes activities associated with emergency (fight
or flight) (E division)
parasympathetic nervous system - Answer active under normal conditions (rest and digest)
(D division)
3 functions of the nervous system - Answer 1. Receives sensory input
Ex. Smell of baking cookies: olfactory receptor → PNS → CNS
2. CNS performs info processing and integration
A. CNS reviews information
B. Stores information as memories
Ex. Smell of baking cookies: evokes pleasant memories of their taste
3. CNS generates appropriate motor response
Ex. Smell of baking cookies: CNS → PNS→ muscles, glands, organs
, 2 kinds of nervous tissue - Answer A. Neurons: nerve cells that transmits impulses between
parts of nervous system.
-3 parts include: cell body, dendrites, and axon(nerve fiber)
-3 types include: sensory neuron- Sensory receptor (PNS→ CNS), Interneuron- (entirely within
CNS), and Motor neuron: CNS→PNS→effector (muscle fiber, organ, gland)
B. Neuroglia: nonconducting nerve cells that support neurons
Nerve signals - Answer action potentials traveling along a neuron; conveys information
action potential - Answer a brief change in electrical conditions at a neuron's membrane
refractory period - Answer portion of axon immediately following the action potential which
is unable to conduct an action potential
-ensures one-way direction of signal (cell body→ axon)
membrane potential - Answer difference in electrical charge between the two sides of a
membrane
resting membrane potential - Answer Polarized plasma membrane (-70mV)
-net number of positively charged ions outside (Na+)
-negatively charged ions inside cell
sodium-potassium pump - Answer membrane protein
-uses ATP to pump 3 Na+ out and 2K+ in the cell
what happens during an action potential? - Answer -conductance of a nerve signal in axons
-all or nothing event; self propagating
-1st sodium gates open (-40mV) resulting in depolarization
-2nd potassium gates open (+30mV) resulting in repolarization
-3rd sodium-potassium pump restores original ionic distribution
Stimulus - Answer activates neuron and begins action potential if threshold is met (-40mV)
-Example: pricked by pin and stimulates mechanoreceptors
Types of active protein channels - Answer voltage gated, ligand gated, and mechanically
regulated