BIO 253 EXAM #2 QUESTIONS WITH CORRECT
ANSWERS | LATEST UPDATE 2026-2027 | GRADED
A+ | 100% ASSURED PASS.
Classification of Receptors by Structure - ANSWER-Free Nerve Endings
Encapsulated Nerve Endings
Free Nerve Endings - ANSWER-Most widely distributed sensory receptor
Exteroceptors, visceroceptors, nociceptors (pain receptors), thermoreceptors, touch
receptors (Root hair plexuses, Merkel disks)
Encapsulated Nerve Endings - ANSWER-Touch and pressure receptors Corpuscles
(touch, pressure, vibration) and stretch receptors (eg muscle spindle measure
muscle length and Golgi tendon organs are activated during excessive contraction &
lead to relaxation as protection)
Classification of Receptors by Location - ANSWER-Exteroceptors
Visceroreceptors
Proprioceptors
Proprioceptors (special type of visceroceptor) - ANSWER-Location: limited to
position of skeletal muscles, tendons, joint capsule
Type of information received: body movement, orientation in space
Tonic proprioceptors: positional information on body or body parts while at rest. Slow
adapting
Phasic proprioceptors: positional information on body or body parts during
movement. Rapid adapting
Exteroceptors - ANSWER-Location: on or near body surface
Type of information received: external environment (pressure, touch, pain,
temperature, vibration)
Visceroceptors (interoceptors) - ANSWER-Location: internally, body organs (viscera)
Type of information received: internal environment (pressure, stretch, chemical,
hunger, thirst)
,The Importance of Cutaneous Sensation - ANSWER-Using a monofilament to check
for sensation on the bottom of the foot
Foreign body (wire) in the toe of a diabetic patient may not trigger appropriate
sensations of pain because of nerve damage (diabetic neuropathy)
Referred Pain - ANSWER-Definition: stimulation of pain receptors in deep structures
may be felt as pain in the skin that lies over the affected organ or in an area of skin
on the body surface far removed from the site of disease or injury.
Cause: convergence (mixing) of sensory nerve impulses from both diseased organ
and skin in the area of referred pain.
Classic example: referred pain often associated with a heart attack in men: sensation
from different locations travel along same pathway (T1-T5 spinal cord), skin on the
chest over the heart , from the tissue of the heart itself, skin areas over the left
shoulder and inner surface of the left arm; brain may feel the pain of a heart attack in
the shoulder or arm; misinterpretation in the brain in regard to the true location of
sensory neurons being stimulated causes referred pain. Clinical importance:
important in correct diagnosis of disease
Components of the Autonomic Nervous System (ANS) - ANSWER-Two divisions:
parasympathetic and sympathetic Mixed Function:
Sensory (afferent) function: monitors internal and external environment in the
periphery and sends it to the CNS
Motor function: CNS controls response to the changes in the environment so that
homeostasis is maintained
Parasympathetic - ANSWER-"Rest and digest"
Dominant controller of most autonomic effectors most of the time
Sympathetic - ANSWER-"fight or flight"
Serving as an "emergency" system
Overall Function of the ANS - ANSWER-Involuntary control of certain systems in
body: Cardiac, respiratory, digestive, urinary, metabolism
A type of Reflex Arc - ANSWER-sensory-integrative-motor pathway. All autonomic
neurons function in reflex arcs; called autonomic reflexes or visceral reflexes Efferent
autonomic regulation ultimately depends on feedback from sensory receptors
Chemoreceptors - ANSWER-Activated by amount or changing concentration of
certain chemicals (glucose, CO2, pH, Na+)
Thermoreceptors - ANSWER-Activated by temperature, either cold or hot
Nociceptors - ANSWER-Activated by intense stimuli → pain sensation
,Thank you for Purchasing this exam
Study Guide. We provide high-
quality academic materials to help
students excel in exams. Our other
Services include but not limited to:
academic research, University &
College assignments writing, essay
writing, Online Classes, and
research projects. Our services are
reliable, affordable, and plagiarism-
free. All the Best in your Exam. For
more information; Contact us at:
or
0R
+254 741484450
Photoreceptors - ANSWER-Located only in the eye; activated by only by light
Osmoreceptors - ANSWER-Located in hypothalamus; activated by changes in
concentration of electrolytes
, Classification of Receptors by Stimulus Detected - ANSWER-Mechanoreceptors
Chemoreceptors
Thermoreceptors
Nociceptors
Photoreceptors
Osmoreceptors
Mechanoreceptors - ANSWER-activated by mechanical stimuli (sAretch, pressure,
filling hollow organ)
Selectively and Sensitivity of Sensory Receptors - ANSWER-Discriminative touch
Normally, sensation can be elicited by a light stroke to the skin.
Examples of specific sites used to verify sensation of discriminative touch
Dual Innervation of Organs - ANSWER-Most systems affected by both divisions of
the ANS
To allow for precise control of effector tissue, one systems always stimulates and the
other one inhibits (brake/accelerator)
Receives input from sympathetic and parasympathetic system, has nerves of both
systems
Dual Innervation: what organs are innervated by only the sympathetic NS? -
ANSWER-Kidney
Adrenal glands
Blood vessels
Sweat glands
If you trace the axon inside the sympathetic chain ganglion, the preganglionic fiber
branches along which pathway? - ANSWER-sends ascending or descending
branches through the sympathetic trunk to synapse with postganglionic neurons in
other chain ganglia
passes through one or more ganglia without synapsing, synapses with a sympathetic
postganglionic neuron
preganglionic - ANSWER-Release Ach
postganglionic - ANSWER-Release Ne
Acetylcholine binds to what kind of receptors. - ANSWER-cholinergic
ANSWERS | LATEST UPDATE 2026-2027 | GRADED
A+ | 100% ASSURED PASS.
Classification of Receptors by Structure - ANSWER-Free Nerve Endings
Encapsulated Nerve Endings
Free Nerve Endings - ANSWER-Most widely distributed sensory receptor
Exteroceptors, visceroceptors, nociceptors (pain receptors), thermoreceptors, touch
receptors (Root hair plexuses, Merkel disks)
Encapsulated Nerve Endings - ANSWER-Touch and pressure receptors Corpuscles
(touch, pressure, vibration) and stretch receptors (eg muscle spindle measure
muscle length and Golgi tendon organs are activated during excessive contraction &
lead to relaxation as protection)
Classification of Receptors by Location - ANSWER-Exteroceptors
Visceroreceptors
Proprioceptors
Proprioceptors (special type of visceroceptor) - ANSWER-Location: limited to
position of skeletal muscles, tendons, joint capsule
Type of information received: body movement, orientation in space
Tonic proprioceptors: positional information on body or body parts while at rest. Slow
adapting
Phasic proprioceptors: positional information on body or body parts during
movement. Rapid adapting
Exteroceptors - ANSWER-Location: on or near body surface
Type of information received: external environment (pressure, touch, pain,
temperature, vibration)
Visceroceptors (interoceptors) - ANSWER-Location: internally, body organs (viscera)
Type of information received: internal environment (pressure, stretch, chemical,
hunger, thirst)
,The Importance of Cutaneous Sensation - ANSWER-Using a monofilament to check
for sensation on the bottom of the foot
Foreign body (wire) in the toe of a diabetic patient may not trigger appropriate
sensations of pain because of nerve damage (diabetic neuropathy)
Referred Pain - ANSWER-Definition: stimulation of pain receptors in deep structures
may be felt as pain in the skin that lies over the affected organ or in an area of skin
on the body surface far removed from the site of disease or injury.
Cause: convergence (mixing) of sensory nerve impulses from both diseased organ
and skin in the area of referred pain.
Classic example: referred pain often associated with a heart attack in men: sensation
from different locations travel along same pathway (T1-T5 spinal cord), skin on the
chest over the heart , from the tissue of the heart itself, skin areas over the left
shoulder and inner surface of the left arm; brain may feel the pain of a heart attack in
the shoulder or arm; misinterpretation in the brain in regard to the true location of
sensory neurons being stimulated causes referred pain. Clinical importance:
important in correct diagnosis of disease
Components of the Autonomic Nervous System (ANS) - ANSWER-Two divisions:
parasympathetic and sympathetic Mixed Function:
Sensory (afferent) function: monitors internal and external environment in the
periphery and sends it to the CNS
Motor function: CNS controls response to the changes in the environment so that
homeostasis is maintained
Parasympathetic - ANSWER-"Rest and digest"
Dominant controller of most autonomic effectors most of the time
Sympathetic - ANSWER-"fight or flight"
Serving as an "emergency" system
Overall Function of the ANS - ANSWER-Involuntary control of certain systems in
body: Cardiac, respiratory, digestive, urinary, metabolism
A type of Reflex Arc - ANSWER-sensory-integrative-motor pathway. All autonomic
neurons function in reflex arcs; called autonomic reflexes or visceral reflexes Efferent
autonomic regulation ultimately depends on feedback from sensory receptors
Chemoreceptors - ANSWER-Activated by amount or changing concentration of
certain chemicals (glucose, CO2, pH, Na+)
Thermoreceptors - ANSWER-Activated by temperature, either cold or hot
Nociceptors - ANSWER-Activated by intense stimuli → pain sensation
,Thank you for Purchasing this exam
Study Guide. We provide high-
quality academic materials to help
students excel in exams. Our other
Services include but not limited to:
academic research, University &
College assignments writing, essay
writing, Online Classes, and
research projects. Our services are
reliable, affordable, and plagiarism-
free. All the Best in your Exam. For
more information; Contact us at:
or
0R
+254 741484450
Photoreceptors - ANSWER-Located only in the eye; activated by only by light
Osmoreceptors - ANSWER-Located in hypothalamus; activated by changes in
concentration of electrolytes
, Classification of Receptors by Stimulus Detected - ANSWER-Mechanoreceptors
Chemoreceptors
Thermoreceptors
Nociceptors
Photoreceptors
Osmoreceptors
Mechanoreceptors - ANSWER-activated by mechanical stimuli (sAretch, pressure,
filling hollow organ)
Selectively and Sensitivity of Sensory Receptors - ANSWER-Discriminative touch
Normally, sensation can be elicited by a light stroke to the skin.
Examples of specific sites used to verify sensation of discriminative touch
Dual Innervation of Organs - ANSWER-Most systems affected by both divisions of
the ANS
To allow for precise control of effector tissue, one systems always stimulates and the
other one inhibits (brake/accelerator)
Receives input from sympathetic and parasympathetic system, has nerves of both
systems
Dual Innervation: what organs are innervated by only the sympathetic NS? -
ANSWER-Kidney
Adrenal glands
Blood vessels
Sweat glands
If you trace the axon inside the sympathetic chain ganglion, the preganglionic fiber
branches along which pathway? - ANSWER-sends ascending or descending
branches through the sympathetic trunk to synapse with postganglionic neurons in
other chain ganglia
passes through one or more ganglia without synapsing, synapses with a sympathetic
postganglionic neuron
preganglionic - ANSWER-Release Ach
postganglionic - ANSWER-Release Ne
Acetylcholine binds to what kind of receptors. - ANSWER-cholinergic
