Receptor Sensation – Biology Chapter 2-6 Test
The key terms of Biology Test include, Receptor Sensation.
General Receptor Sensation
– Pain, temperature, touch (many types), and proprioception
Cerebrum
– Controls voluntary motor
– Understands and interprets sensory information that reaches a conscious level
Cerebellum
– Coordinates complex motor activities
Brainstem
– Relay center for sensory and motor information
– Controls and monitors nonconscious activities (breathing, heart rate)
Spinal Cord
– Transmits motor information TO the body (efferent) and transmits sensory information TO the brain (afferent)
Derivatives of Neural Crest Cells
– Cell bodies of dorsal root ganglia
– Cell bodies of sensory cranial nerve ganglia, V, VII, VIII, IX, X
– Cell bodies of autonomic motor ganglia, ex. sympathetic chain ganglia
-> Sympathetic trunks: Behind the mediastinum, lateral to vertebral column and a series of ganglia in a “chain”
– Schwann cells (glia): Myelinates PNS
– Satellite or capsule cells of sensory and motor ganglia (schwann cells; serving as blood-ganglion barrier)
– Cells of adrenal medulla
– Skeletal bones and CT of face and anterior neck
– Parts of most of the bones in the orbital cavity and orbital fat
-> Optic cup is present before bone and helps determine orbit
– Perhaps pia-arachnoid
– Eye related:
-> Melanocytes of uveal tract
-> Corneal endothelium and stroma
-> Most of sclera
-> Ciliary muscle and stroma
Parts of Structural Nervous System
– CNS: Brain, spinal cord, retina/optic nerve, and CN 1
– PNS: CN, spinal nerves, associated ganglia
– Glia support in both systems
Neuron Classification
– By their number of neurites/processes (number of axons and dendrites)
– Unipolar: “Appear” to have one process. Classic for transmitting general sensation. Ex. Typical dorsal root (spinal) ganglia
– Unipolar are also present in the mesencephalic nucleus of V in te pons/midbrain
– Bipolar neurons: Two process, characteristic of special senses. Found in retina, spinal ganglion (auditory), and olfactory bulb
– Multiple neurons: 3 or more processes; only one axons. Most neurons in the brain are multipolar
-> Ventral cells
-> Pyramidal cells: In cerebral cortex, has pyramid shaped cell body; apical dendrite toward brain surface and axon arises from base
-> Purkinje cells: In cerebellum, flask-shaped body, large dendrite arborization; axon arises from base of flask
-> Autonomic cells: Some sympathetic
-> Ventral horn cell: Large is alpha and small is gamma
Guillain-Barre Syndrome
– Autoimmune attack on the myelin sheath of PNS axons causing weakness, numbness, or paralysis
– Unknown cause but may occur following stomach flu infection
– No cure but symptoms do improve on their own
– Miller Fisher syndrome: One form of GBS. Started with paralysis of the EOMs and gait issues. First complaint will be diplopia
Charcot-Marie-Tooth
– PNS disease
– Most common inherited peripheral neuropathy
– Mutation of the PMP22 (peripheral myelin protein) gene on Chromosome 17; duplication of gene leading to increased production of PMP22
– Progressive muscle weakness
– Greatly decreased conduction in peripheral nerves
– Cycles of demyelination and remyelination
Oligodendrocytes v Schwann Cells
– On average, oligodendrocytes myelinate many axons but about 15 axonal internodes
– In contrast, each schwann cell envelopes one internode of only one axon
– Schwann cell and axon contact “turns on” genes in schwann cells to produce myelin
– Astrocyte presence “turns on” genes in oligodendrocytes to produce myelin
– Both contain myelin basic proteins: Myelin compaction
– Both contain myelin-associated glycoprotein: MAG; important for myelin process initiation
-> Thought to be adhesion molecule and found immediately adjacent to axon
Obstacles to Regeneration in PNS
– Scar formation is a physical barrier
– Proximity of injury to the cell body the closer to cell body, the less likely to regenerate
– Distance between proximal and distal stump (surgery can approximate them via the epineurium)
– Severity of injury
Oligodendrocyte Precursor Cells (OPC)
– Something is wrong with remyelination once it hits the stage with the OPCs
– OPCs are present during development and some in adult brain
– However in injury, remyelination becomes arrested at the step of OPC
Special Receptors
– Found in one place, one function
– Retina: Vision, stimulus is light
– Cochlea: Hearing, stimulus is sound
General Receptors
– Found throughout the body, superficial and deep
– Respond to many different kinds of stimuli, rather than single one
General Receptor Sensation
– Pain, temperature, touch (many types), and proprioception
Cerebrum
– Controls voluntary motor
– Understands and interprets sensory information that reaches a conscious level
Cerebellum
– Coordinates complex motor activities
Brainstem
– Relay center for sensory and motor information
– Controls and monitors nonconscious activities (breathing, heart rate)
Spinal Cord
– Transmits motor information TO the body (efferent) and transmits sensory information TO the brain (afferent)
Derivatives of Neural Crest Cells
– Cell bodies of dorsal root ganglia
– Cell bodies of sensory cranial nerve ganglia, V, VII, VIII, IX, X
– Cell bodies of autonomic motor ganglia, ex. sympathetic chain ganglia
-> Sympathetic trunks: Behind the mediastinum, lateral to vertebral column and a series of ganglia in a “chain”
– Schwann cells (glia): Myelinates PNS
– Satellite or capsule cells of sensory and motor ganglia (schwann cells; serving as blood-ganglion barrier)
– Cells of adrenal medulla
– Skeletal bones and CT of face and anterior neck
– Parts of most of the bones in the orbital cavity and orbital fat
-> Optic cup is present before bone and helps determine orbit
– Perhaps pia-arachnoid
– Eye related:
-> Melanocytes of uveal tract
-> Corneal endothelium and stroma
-> Most of sclera
-> Ciliary muscle and stroma
Parts of Structural Nervous System
– CNS: Brain, spinal cord, retina/optic nerve, and CN 1
– PNS: CN, spinal nerves, associated ganglia
– Glia support in both systems
Neuron Classification
– By their number of neurites/processes (number of axons and dendrites)
– Unipolar: “Appear” to have one process. Classic for transmitting general sensation. Ex. Typical dorsal root (spinal) ganglia
– Unipolar are also present in the mesencephalic nucleus of V in te pons/midbrain
– Bipolar neurons: Two process, characteristic of special senses. Found in retina, spinal ganglion (auditory), and olfactory bulb
– Multiple neurons: 3 or more processes; only one axons. Most neurons in the brain are multipolar
-> Ventral cells
-> Pyramidal cells: In cerebral cortex, has pyramid shaped cell body; apical dendrite toward brain surface and axon arises from base
-> Purkinje cells: In cerebellum, flask-shaped body, large dendrite arborization; axon arises from base of flask
-> Autonomic cells: Some sympathetic
-> Ventral horn cell: Large is alpha and small is gamma
Guillain-Barre Syndrome
– Autoimmune attack on the myelin sheath of PNS axons causing weakness, numbness, or paralysis
– Unknown cause but may occur following stomach flu infection
– No cure but symptoms do improve on their own
– Miller Fisher syndrome: One form of GBS. Started with paralysis of the EOMs and gait issues. First complaint will be diplopia
Charcot-Marie-Tooth
– PNS disease
– Most common inherited peripheral neuropathy
– Mutation of the PMP22 (peripheral myelin protein) gene on Chromosome 17; duplication of gene leading to increased production of PMP22
– Progressive muscle weakness
– Greatly decreased conduction in peripheral nerves
– Cycles of demyelination and remyelination
Oligodendrocytes v Schwann Cells
– On average, oligodendrocytes myelinate many axons but about 15 axonal internodes
– In contrast, each schwann cell envelopes one internode of only one axon
– Schwann cell and axon contact “turns on” genes in schwann cells to produce myelin
– Astrocyte presence “turns on” genes in oligodendrocytes to produce myelin
– Both contain myelin basic proteins: Myelin compaction
– Both contain myelin-associated glycoprotein: MAG; important for myelin process initiation
-> Thought to be adhesion molecule and found immediately adjacent to axon
Obstacles to Regeneration in PNS
– Scar formation is a physical barrier
– Proximity of injury to the cell body the closer to cell body, the less likely to regenerate
– Distance between proximal and distal stump (surgery can approximate them via the epineurium)
– Severity of injury
Oligodendrocyte Precursor Cells (OPC)
– Something is wrong with remyelination once it hits the stage with the OPCs
– OPCs are present during development and some in adult brain
– However in injury, remyelination becomes arrested at the step of OPC
Special Receptors
– Found in one place, one function
– Retina: Vision, stimulus is light
– Cochlea: Hearing, stimulus is sound
General Receptors
– Found throughout the body, superficial and deep
– Respond to many different kinds of stimuli, rather than single one
General Receptor Sensation
– Pain, temperature, touch (many types), and proprioception