Bio201 Quiz5 Review Guide
Central Nervous System:
1. What two structures make up the CNS? Brain and spinal cord
2. Describe the roles of the three types of neurons involved in a reflex.
Sensory neurons- Deliver information to CNS
Motor neurons- Commands to perphial effectors
Interneurons- Interpret, plan, and coordinate signals in and out
3. 1 neural reflex = _?_ I nueral reflex produces 1 motor response
4. Diagram AND label the five steps that occur in a neural reflex. Make sure to keep the sensory and motor neurons straight!
Step 1: Arrival of stimulus, activation of receptor -physical or chemical changes
Step 2: Activation of sensory neuron -Graded depolarization
Step 3: Information processingby postsynaptic cell triggered by nuerotransmitters
Step 4: Activation of motor neuron action potential
Step 5: Response of peripheral effector trigger by nuerotrnsmitter
5. Compare and contrast innate and acquired reflexes.
Innate reflexes- Basic nueral reflexes and is former before birth
Acquired reflexes are rapid automatic and learned motor patterns
6. Compare and contrast somatic and visceral reflexes.
Somatic- Involuntary control of nervous system
Superficial refelexes of skin, mucous membrane
Stretch reflexes
Visceral reflexes- ( autonomic reflex)
Control system othe than muscular system
7. Compare and contrast monosynaptic and polysynaptic reflexes.
Monosynaptic- is a sensory neuron synapses directly onto motor neuron
Polysynaptic- At least 1 internueron between sensory neuron and motor nueron
8. Compare and contrast spinal reflexes and cranial reflexes.
Spinal- occurse in spinal cord and is faster
Cranial- occurs in brain and is slower
9. Is there an interneuron in a monosynaptic spinal reflex? Explain! What type of delay are we talking about with a monosynaptic spinal reflex (i.e. the stretch reflex)?
They do not have an interneuron and they have a slight delay between sensory input and motor output
10. Explain the roles of intrafusal and extrafusal muscle fibers in the stretch reflex as well as the adjustment of muscles tension in postural reflexes.
Intrafusal muscle fibers- innervated by sensory and motor neurons
Extrafusal – maintain and contract muscle
11. Diagram AND explain the events that occur during the flexor reflex. Make sure to include that little interneuron!
12. Explain the importance of reciprocal inhibition. Give an example!
13. Diagram the events which occur during the tendon reflex. What would happen to us if we didn’t have this reflex?
14. What does ipsilateral mean? How about contralateral?
Ipsolateral= same side
Contralateral= Opposite side
15. Now that you know what ipsilateral and contralateral mean, diagram an example of the crossed extensor reflex.
16. Review the meanings of rostral and caudal. Rostal= towards the forehead Caudal= toward the spinal cord
17. What region comprises the bulk of the volume of the human brain? The cerebrum makes up most of the brain
18. Explain the difference between a gyrus and a sulcus.
Gyrus= Folds in the brain
Sulci= Grooves in the brain
19. What is a fissure in the brain? This divides cerebral hemispheres in the brain
20. Explain the difference between nuclei and tracts in the brain.
Nuclei= Deeper masses of gray matter
Tracts= Bundles of axons ( white matter)
21. Compare and contrast grey and what matter in the brain.
Gray matter= Neuron bodies, synapses, and dendrites
White matter= Bundles of myliniated axons
22. List the three meninges and the two spaces. Which of these three is located deepest (closest to the brain)? Under which layer does CSF circulate? Under which of these are the dural sinuses located? Where would a subdural hematoma occur if someone got hit in the head?
Dura mater- is the outer most tough membrane it is against the bone -This is where the dural sinuses are located that drain blood from brain -This is the subdural;space this is where a hemotoma occurs
-Arachnoid layer- Subarchnoid
