BPK 105 Study Guide - Midterm Guide: Spinothalamic Tract, Referred Pain, Carotid Body
27 Apr 2018
School
Department
Course
Professor
Module 5 - Terminology and Study Guide
Terminology
1. chemoreceptors (Section 9.2): a sensory cell or organ responsive to chemical
stimuli.
Carotid bodies are small structures that lie near the carotid sinuses, and aortic bodies lie near
the aortic arch. These structures contain sensory receptors that respond to changes in blood O2
concentration, CO2 concentration, and pH. Because they are sensitive to chemical changes in
the blood, they are called chemoreceptors.
2. photoreceptors (Section 9.2): a structure in a living organism, especially a sensory
cell or sense organ, respond to light.
Cone: Photoreceptor cell in the retina of the eye with cone-shaped photoreceptive process;
important in color vision and visual acuity.
Rod: Photoreceptor cell in the retina of the eye with a rod-shaped photoreceptive process; very
light-sensitive cell that is important in dim light
3. local anesthesia (Section 9.3): a treatment where chemical anesthetics are injected
near a sensory receptor or nerve, resulting in reduced pain sensation.
Anesthesia:Loss of sensation; may be a pathological condition or may be induced temporarily to
facilitate medical action.
4. gate control theory (Section 9.3): Pain sensations can also be influenced by inherent
control systems. Sensory axons from tactile receptors in the skin have collateral
branches that synapse with neurons in the posterior horn of the spinal cord. Those
neurons, in turn, synapse with and inhibit neurons that give rise to the spinothalamic
tract, a sensory pathway that relays pain sensations to the brain (see table 8.4). For
example, rubbing the skin in the area of an injury stimulates the tactile receptors,
which send action potentials along the sensory axons to the spinal cord. According
to the gate control theory, these action potentials “close the gate” and inhibit action
potentials carried to the brain by the spinothalamic tract.
The gate control theory of pain asserts that non-painful input closes the "gates" to painful
input, which prevents pain sensation from traveling to the central nervous system. Therefore,
stimulation by non-noxious input is able to suppress pain.
5. referred pain (Section 9.3): Referred pain is perceived to originate in a region of the
body that is not the source of the pain stimulus. Most commonly, we sense referred
pain when deeper structures, such as internal organs, are damaged or inflamed
(figure 9.3).
6. Olfactory (Section 9.4): Relating to the sense of smell.
Document Summary
Terminology: chemoreceptors (section 9. 2): a sensory cell or organ responsive to chemical stimuli. Carotid bodies are small structures that lie near the carotid sinuses, and aortic bodies lie near the aortic arch. These structures contain sensory receptors that respond to changes in blood o2 concentration, co2 concentration, and ph. Because they are sensitive to chemical changes in the blood, they are called chemoreceptors: photoreceptors (section 9. 2): a structure in a living organism, especially a sensory cell or sense organ, respond to light. Cone: photoreceptor cell in the retina of the eye with cone-shaped photoreceptive process; important in color vision and visual acuity. Rod: photoreceptor cell in the retina of the eye with a rod-shaped photoreceptive process; very light-sensitive cell that is important in dim light. 3. local anesthesia (section 9. 3): a treatment where chemical anesthetics are injected near a sensory receptor or nerve, resulting in reduced pain sensation.
