age 1 of 182
BIO 141 EXAM 2 STUDY GUIDE 2025/2026 QUESTIONS
BANK AND VERIFIED CORRECT SOLUTIONS WITH
RATIONALES || 100% GUARANTEED PASS <RECENT
VERSION>
What is acetylcholine (Ach) ......ANSWER........the most plentiful
neurotransmitter in the body, released by nerve cells, especially
active in neuromuscular junctions (cardiac, skeletal, and smooth)
Excitatory: muscle contraction
Inhibitory: reduction of signaling, like reduction of HR
Sarin gas ......ANSWER........inhibits AChl; interferes with the
degradation of ACh in the synapse (neuromuscular junction);
leads to muscle tetani, inability to control the muscles.
,age 2 of 182
Which receptors pick up ACh ......ANSWER........cholinergic
receptors
Atropine ......ANSWER........inhibits muscarinic ACh receptors
CNS ......ANSWER........spinal cord and tissue, sensory info,
executing motor commands, higher functioning, both cell bodies
and axons
PNS ......ANSWER........all neural tissue except CNS, mainly
composed of nerves grouped together in bundles of axons
the only place to find cell bodies are in ganglions
Afferent neurons ......ANSWER........sensory neurons
3 classes of afferent neurons ......ANSWER........somatic
visceral
,age 3 of 182
special
somatic afferent neurons ......ANSWER........neurons of the bones,
muscles, and skin
visceral afferent neurons ......ANSWER........neurons of the organs
special afferent neurons ......ANSWER........neurons involved in
hearing, sight, taste, smell
interneurons ......ANSWER........only located in the CNS
efferent neurons ......ANSWER........motor neurons
2 classes of efferent neurons ......ANSWER........somatic and
visceral
, age 4 of 182
Visceral Sensory Receptors ......ANSWER........input from internal
organs, many of these receptors are chemoreceptors (use
chemicals)
Somatic Sensory Neurons ......ANSWER........collect information
from the skins, muscles, joints, and bones, monitored by receptor
cells, stimulus will cause gated-channels to open and depolarize
the neuron
Why are some parts of the body more sensitive than others?
......ANSWER........the density of sensory neurons vary over
different tissues; the more sensory neurons, the more space the
brain requires to integrate the information
Ganglia ......ANSWER........bulge of multiple cell bodies (100-
1000 neurons in autonomic ganglia)
BIO 141 EXAM 2 STUDY GUIDE 2025/2026 QUESTIONS
BANK AND VERIFIED CORRECT SOLUTIONS WITH
RATIONALES || 100% GUARANTEED PASS <RECENT
VERSION>
What is acetylcholine (Ach) ......ANSWER........the most plentiful
neurotransmitter in the body, released by nerve cells, especially
active in neuromuscular junctions (cardiac, skeletal, and smooth)
Excitatory: muscle contraction
Inhibitory: reduction of signaling, like reduction of HR
Sarin gas ......ANSWER........inhibits AChl; interferes with the
degradation of ACh in the synapse (neuromuscular junction);
leads to muscle tetani, inability to control the muscles.
,age 2 of 182
Which receptors pick up ACh ......ANSWER........cholinergic
receptors
Atropine ......ANSWER........inhibits muscarinic ACh receptors
CNS ......ANSWER........spinal cord and tissue, sensory info,
executing motor commands, higher functioning, both cell bodies
and axons
PNS ......ANSWER........all neural tissue except CNS, mainly
composed of nerves grouped together in bundles of axons
the only place to find cell bodies are in ganglions
Afferent neurons ......ANSWER........sensory neurons
3 classes of afferent neurons ......ANSWER........somatic
visceral
,age 3 of 182
special
somatic afferent neurons ......ANSWER........neurons of the bones,
muscles, and skin
visceral afferent neurons ......ANSWER........neurons of the organs
special afferent neurons ......ANSWER........neurons involved in
hearing, sight, taste, smell
interneurons ......ANSWER........only located in the CNS
efferent neurons ......ANSWER........motor neurons
2 classes of efferent neurons ......ANSWER........somatic and
visceral
, age 4 of 182
Visceral Sensory Receptors ......ANSWER........input from internal
organs, many of these receptors are chemoreceptors (use
chemicals)
Somatic Sensory Neurons ......ANSWER........collect information
from the skins, muscles, joints, and bones, monitored by receptor
cells, stimulus will cause gated-channels to open and depolarize
the neuron
Why are some parts of the body more sensitive than others?
......ANSWER........the density of sensory neurons vary over
different tissues; the more sensory neurons, the more space the
brain requires to integrate the information
Ganglia ......ANSWER........bulge of multiple cell bodies (100-
1000 neurons in autonomic ganglia)
