Biology Flashcards - Nervous System
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Biology Flashcards - Nervous System
Biology Flashcards Nervous System
Biology Flashcards - Nervous System Kaplan MCAT B96-B105
What is the function of a dendrite?
A dendrite conducts nerve impulses towards the cell body.
What is the function of an axon?
An axon conducts nerve impulses away from the cell body.
What is the composition of a myelin sheath?
In the CNS, myelin is composed of the membranes of oligodendrocytes.
In the PNS, myelin is composed of the membranes of Schwann cells.
What protein complex is responsible for the resting potential (-70mV) of a neuron?
pump is responsible for the neuron's resting potential.
(T/F) In a resting neuron, Na
concentration is higher inside the cell than outside the cell.
concentration is higher outside a resting neuron.
ions rush into or out of the cell during depolarization?
ions rush into the cell during depolarization.
ions rush into or out of the cell during repolarization?
During repolarization, K
ions rush into the cell.
(T/F) A neuron can conduct during the refractory period.
False, the neuron is unable to respond to stimulus during the refractory period.
What is hyperpolarization?
Hyperpolarization refers to a state where the potential across the membrane is more negative than the resting potential.
What is saltatory conduction?
Saltatory conduction is the "jumping" of an action potential between the unmyelinated Nodes of Ranvier.
What happens when an action potential reaches a synapse (in a mammal)?
When an action potential reaches a synapse, the electrical signal causes the release of neurotransmitters from the presynaptic membrane into the synapse.
What is the function of a sensory (afferent) neuron?
A sensory neuron carries impulses from sensory organs to the brain and spinal cord.
What is the function of a motor (efferent) neuron?
A motor neuron transmits impulses from the brain and spinal cord to muscles and glads.
Which type of neuron serves as a link between motor and sensory neurons?
Interneurons (associate neurons) link sensory and moto neurons.
What are the two major subsystems of the nervous system?
The two major subsystems of the nervous system are the central nervous system and the peripheral nervous system.
What are the components of the central nervous system?
The central nervous system comprises of the brain and spinal cord.
(T/F) Gray matter is composed of axons and white matter is composed of cell bodies.
False, gray matter is composed of cell bodies and white matter is composed of axons.
What is the largest part of the human brain?
The cerebral cortex is the largest part of the human brain.
What is the function of the cerebral cortex?
The cerebral cortex processes and integrates sensory input and motor response and controls memory.
What is the function of the hypothalamus?
The hypothalamus is responsible for visceral functions such as hunger, thirst, and sex drive.
(T/F) The cerebral cortex is the relay center for visual and auditory impulses.
False, the midbrain is the relay center for visual and auditory impulses.
What are the components of the hindbrain?
The hindbrain is composed of the cerebellum, pons, and medulla oblongata.
What is the function of the cerebellum?
The cerebellum is responsible for coordination.
What part of the brain controls autonomic activities?
The medulla oblongata controls autonomic activities.
What are the four regions of the spinal cord?
The four regions of the spinal cord are cervical, thoracic, lumbar, and sacral.
(T/F) Dorsal root ganglia house the cell bodies of sensory root fibers.
(T/F) Sensory nerves enter the spinal cord ventrally and motor nerves leave the spinal cord dorsally.
False, sensory nerves enter dorsally and motor nerves leave ventrally.
Illustrate the hierarchy of the divisions of the peripheral nervous system.
What is the difference between a polysnaptic and monosynaptic reflex?
A monosynaptic reflex involves only one sensory neuron and one motor neuron.
A polysynaptic reflex involves one or more interneurons, in addition to a sensory neuron and motor neuron.
Which part of the nervous system readies the body for "fight or flight"?
The sympathetic nervous system readies the body for "fight of flight".
What is the function of the parasympathetic division of the nervous system?
The parasympathetic division opposes the sympathetic division by slowing the body down and conserving energy.
Which division of the nervous system inhibits digestion?
The sympathetic division inhibits digestion.
Name the following components of the eye.
5. Aqueous humor
6. Ciliary body
8. Optic nerve
12. Vitreous humor
Which type of photoreceptor cell is specialized for color vision?
Which type is specialized for low light conditions?
Cones are for color and rods are for night vision.
What is the fovea?
The fovea is the region of the retina with a high density of cones.
What are the components of the middle ear?
The middle ear is composed of the tympanic membrane, malleus, incus, and stapes.
What are the components of the inner ear?
The inner ear is composed of the cochlea (which contains the organ of Corti) and the semicircular canals.
Name the following components of the ear:
1. external auditory canal
2. tympanic membrane (eardrum)
5. stapes (stirrup)
7. Eustachian tube
8. oval window
9. round window
11. cochlear nerve
12. semicircular canals
14. balance nerve
15. vestibular nerve
16. facial nerve
17. temporal bone
20. internal auditory canal to brain
22. external ear