Nervous System

Explain the difference between afferent neurons and efferent neurons.

Afferent neurons: neurons that have axons run through the nerves carrying information to central nervous system from peripheral (towards = a in spanish and away from receptor) efferent neurons: axons run through nerves with information going to peripheral from central (exit = going away)

If we're looking at the brain from the top, what major part will we see (the most superficial part)? (A) Cerebrum (B) Midbrain (C) Medulla (D) Brain Stem

(A) Cerebrum The Cerebrum is the most superficial part of the brain at the top.

What type of neurons are found in the central nervous system? in the peripheral nervous system? in the autonomic nervous system?

-CNS: interneurons -PNS: motor and sensory neurons -ANS: preganglionic and postganglionic neurons (special type of motor and sensory)

In what direction do motor neurons and sensory neurons flow?

-Motor neurons start in the central nervous system and extends into peripheral nervous system - sensory is the opposite

Provide a brief description of its purpose of each of the following glial cells astrocyte: ependymal cells: microglia: oligodendrocyte: Schwann cell:

-astrocyte: nourish neurons and form BBB -ependymal: produce CSF -microglia: ingest and break down waste products and pathogens -oligodendrocytes: produce myelin in CNS Schwann: produce myelin in PNS

What is the gray matter in the brain known as? What if they are inside the white matter?

-cortex; gray matter covering the cerebellum is the cerebellar cortex -nuclei

What nerves does the peripheral nervous system consist of? How do they function?

-cranial nerves: come out of brain and go through the skull on their way between the central and peripheral nervous system -spinal nerves: come out of the spinal cord and pass through spine between the central and peripheral system

Match the functions with the brain structures. A. higher order functioning B.memory C. relays sensory and motor signals to cerebrum D. controls voluntary movement E. autonomic functioning F. allows thinking, reasoning, feelings G. sleep, circadian rhythm H. homeostasis (feeding, fornication, fighting, fleeing) I. coordinates movement J. relays auditory and visual info to other parts of brain and control eye movement 1. basal ganglia 2. cerebrum 3. hippocampus 4. cerebral cortex 5. thalamus 6. hypothalamus 7. midbrain 8. cerebellum 9. medulla 10. pons

1. D Basal ganglia (gang of neurons) control voluntary movement. 2. F It gives the ability to think, to reason, logic, intuition, emotion, voluntary action control 3. B Hippocampus is part of limbic system and plays a role in memory 4. A Cerebral cortex functions in higher order functioning 5. C Thalamus sends sensory and motor signals to cerebrum for processing and integration. 6. H Hypothalamus is the control center of the endocrine system, controls pituitary gland, homeostasis 7. J Midbrain relays auditory and visual info between hindbrain and forebrain, controls eye movement 8. I. control and coordinate movement of muscles; cannot initiate 9. E Medulla controls breathing, heart rate, blood pressure, respiratory rate, automatic, involuntary 10. G Pons controls sleep, circadian rhythm

Match the correct association 1. gray matter 2. white matter A. myelinated/axons B. unmyelinated/cell bodies

1. gray matter -> B. unmyelinated 2. white matter -> A. myelinated

Explain what a preganglionic neuron is.

A preganglionic neuron is a special motor neuron in the autonomic nervous system that extends from the central nervous system to the ganglia (cell body group) of the peripheral system

Which statements are true? I. Motor neurons are efferent neurons that leave the spinal cord from the ventral side. II. Motor neurons are efferent neurons that leave the spinal cord from the dorsal side. III. Sensory neurons are efferent neurons that leave the spinal cord from the dorsal side. A) I only B) II only C) I and III only D) III only

A) I only Motor neurons are efferent neurons that leave the spinal cord from the ventral side (front side of spinal cord). Sensory neurons are afferent neurons that enter the spinal cord from the dorsal side (back side of spinal cord)

Where do the first neurons of the sympathetic and parasympathetic NS start? A) beginning of spinal cord at brainstem or end; the middle of spinal cord B) the middle of spinal cord; beginning of spinal cord at brainstem or end C) the middle of spinal cord; the middle of spinal cord D)the beginning of spinal cord at brainstem; beginning of spinal cord at brainstem

A) beginning of spinal cord or end; the middle of spinal cord

What is the order of the spinal cord regions? A) cervical, thoracic, lumbar, sacral B) thoracic, cervical, lumbar, sacral C) cervical, lumbar, thoracic, sacral D) cervical, thoracic, sacral, lumbar

A) cervical, thoracic, lumbar, sacral

Which of the following accurately describes sensory neurons? A) sensory neurons are afferent and enter the spinal cord on the dorsal side. B) Sensory neurons are efferent and enter the spinal cord on the dorsal side. C) Sensory neurons are afferent and enter the spinal cord on the ventral side. D) Sensory neurons are efferent and enter the spinal cord on the ventral side.

A) sensory neurons are afferent and enter the spinal cord on the dorsal side.

Match the receptors that respond to a sense A) position B) vibration C) touch D) pain E) temperature 1) nociceptors 2) mechanoreceptors 3) thermoreceptors

A, B, C: 2) Mechanoreceptors respond to position (more in capsules of joints), vibration, touch (both in deep skin) D: 1) Nociceptors respond to pain (bare nerve endings) E: 3) Thermoreceptors detect temperature (bare nerve endings)

Match the corresponding parts in the embryo brain with the parts in the adult brain. A. Prosencephalon B. Mesencephalon C. Rhombencephalon 1. Hindbrain 2. Forebrain 3. Midbrain

A. Prosencephalon -> 2. Forebrain B. Mesencephalon -> 3. Midbrain C. Rhombencephalon -> 1. Hindbrain

What is the correlation between the amount of force and number of motor units?

As the amount of force increases, the number of motor units increases.

The hindbrain contains the I. metencephalon II. myelencephalon III. diencephalon A) I, II, and III B) I and II C) III only D) II and III

B) I and II The hindbrain (rhombencephalon) contains the metencephalon and the myelencephalon.

What's the difference between monosynaptic reflex and polysynaptic reflex? A) monosynaptic has only 1 neuron while polysynaptic has more than one neuron involved B) Monosynaptic reflex has 1 synapse between the motor and sensory neuron while polysynaptic has multiple synapses between the motor and sensory neuron C) polysynaptic has 1 or more synapses between the sensory and motor neuron while monosynaptic has none

B) Monosynaptic reflex has 1 synapse between the motor and sensory neuron while polysynaptic has multiple synapses between the motor and sensory neuron

Which is the right definition of a nucleus in the nervous system? A) a collection of axons of neurons in the central nervous system B) a collection of cell bodies of neurons in the central nervous system C) a collection of axons of neurons in the peripheral nervous system D) a collection of cell bodies of neurons in the peripheral nervous system

B) a collection of cell bodies of neurons in the central nervous system

What does the cerebrum NOT include? A) frontal lobe B) cerebellum C) parietal lobe D) temporal lobe

B) cerebellum

Which of the following components does NOT affect the magnitude of the force that is created by the muscle? A) size of the motor unit B) number of muscles involved C) number of motor units involved D) the thickness of the muscle cells

B) number of muscles involved The magnitude of the muscle's force is affected by the size of the motor unit (more muscle fibers = larger force), number of motor units involved (more motor units = larger force), the thickness of the muscle cell (more actin and myosin = more thickness = larger force = thickness)

When a lower motor neuron fires an action potential how many skeletal muscle cells in that motor unit contract? A. One B. Some C. All D. It depends

C) All

Which of the following does the central nervous system include? I. brain II. spinal cord III. muscles A) I only B) II only C) I and II D) I and III

C) I and II The central nervous system includes the brain and the spinal cord.

Which of the following correctly describes a difference between nerves and tracts? A) Nerves are seen in the CNS; tracts are seen in the PNS B) Nerves have cell bodies in nuclei; tracts have cell bodies in ganglia C) Nerves may carry more than one type of info; tracts can only carry one type of info D) nerves contain only one neuron; tracts contain many neurons

C) Nerves may carry more than one type of info; tracts can only carry one type of info

What is the target organ of the motor neurons in the somatic nervous system? Where do the dendrites and cell body of the motor neuron originate? A) smooth muscle; extremities B) cardiac muscle; spinal cord C) skeletal muscle; spinal cord D) skeletal muscle; brain

C) skeletal muscle; spinal cord

What is a collection of cell bodies called in the CNS? in the PNS?

CNS: nucleus PNS: ganglia

Which is the correct association of the structures in the peripheral system? A) Ganglia carry axons of neurons; nerves carry soma of neurons B) Ganglia and nerves carry axons of neurons C) Ganglia and nerves carry soma of neurons D) Ganglia carry the soma of the neurons; nerves carry the axons of neurons

D) Ganglia carry the soma of the neurons; nerves carry the axons of neurons

The forebrain contains the I. metencephalon II. telencephalon III. diencephalon A) I, II, and III B) II only C) III only D) II and III

D) II and III The forebrain (prosencephalon) contains the telencephalon and diencephalon.

Which is the right definition of a ganglia in the nervous system? A) a collection of axons of neurons in the central nervous system B) a collection of cell bodies of neurons in the central nervous system C) a collection of axons of neurons in the peripheral nervous system D) a collection of cell bodies of neurons in the peripheral nervous system

D) a collection of cell bodies of neurons in the peripheral nervous system

What is a motor unit? A) many motor neurons and many muscle fibers B) many motor neurons and one muscle fiber C) one motor neuron and one muscle fiber D) one motor neuron and all the individual muscle fibers it innervates

D) one motor neuron and all the individual muscle fibers it innervates (multiple skeletal muscle cells)

Which of the following would most likely NOT be seen in an individual having a panic attack? A. Bronchodilation B. Decreased oral secretions C. Vasoconstriction of cutaneous vessels D. Pupillary constriction

D. While not explicitly stated, the physical manifestations of a panic attack are the result of uninhibited overstimulation of the sympathetic nervous system (the "stress response" discussed in the passage). A person experiencing a panic attack feels quite the same effects at a person running away from a salivating lion. Sympathetic stimulation leads to bronchodilation (choice A would be seen and can be eliminated), decreased oral secretions (choice B would be seen and can be eliminated), and vasoconstriction of skin vessels (choice C would be seen and can be eliminated). However, pupillary dilation would be expected with sympathetic stimulation, not constriction (choice D would not be seen and is the correct answer choice). Picture a stressed, scared person; they are breathing deeply, have dry mouth, and are pale.

What would be the difference in the motor unit of a muscle in the finger compared to the muscle in the thigh?

One motor neuron would innervate many more muscle fibers (a fascicle has many muscle cells) in the thigh than the finger, having a larger motor unit.

Explain what a postganglionic neuron is.

Postganglionic neurons are a special sensory neurons that synapse with preganglionic neurons and send the signal to target organ/effector organ.

What do the following parts of the embryo brain become in the adult brain? Prosencephalon: Mesencephalon: Rhombencephalon:

Prosencephalon (forebrain)->cerebrum mesencephalon (midbrain)->midbrain rhombencephalon (hindbrain) ->pons, medulla, cerebellum

What are muscle spindles?

Sensory receptors within muscles -run parallel to muscles -sensitive to changes in muscle length and rate of length of change -regulate contraction of muscles via stretch reflex mechanism (prevents overstretching) Think: sensitive to lengthening, so opposite action = shorten and not over stretch

Explain how the motor neuron contracts muscles through its functions from the brain.

The brain creates AP ->dendrites of somatic motor neuron ->picks up signal-> on the ventral side, electrical signal passes through the axon of somatic motor neuron (in the PNS)->axon terminal (next to cell membrane of target skeletal muscle) (NMJ)->releases Ach to bind to receptor proteins on post synaptic neuron to create an AP->muscle contraction

What is the difference between the location of the motor and sensory neuron in the somatic nervous system?

The cell body of the motor neuron is found inside the gray matter while the cell body of the sensory neuron is found in the dorsal root ganglia (neurons outside spinal cord and brain) in the PNS

What's the difference between the cerebrum and cerebellum?

The cerebrum is known for higher order functions. The cerebellum is for basic involuntary movement and balance.

What happens to the size of nerves as they move distally?

The nerves branch repeatedly to their target locations, and become smaller.

How are distal parts of the body connected to the spine?

The nerves from the spinal cord branch out until they reach distal ends.

Which is the correct amounts of the cranial and spinal nerves? There are 12 cranial nerves; there are 31 spinal nerves or there are 31 cranial nerves; there are 12 spinal nerves

There are 12 cranial nerves; there are 31 spinal nerves

How are the spinal roots organized relative to the spine?

There is a root in the front (ventral side) which contain the efferent neurons and a root in the back (dorsal side) which contain the afferent neurons. The two roots combine together in spinal nerves (mixed nerves of efferent and afferent neurons)

For the most part, how much consciousness is involved in the autonomic nervous system.

Very little to none. All these jobs are done without us "telling" the body to do it.

Explain the exception of the sympathetic NS.

When going to adrenal medulla, it is a single preganglionic neuron and uses Ach.

A disease results in the death of Schwann cells. Which portion of the NS is NOT likely to be affected? a) CNS b) somatic nervous system c) ANS d) parasympathetic nervous system

a) CNS

Which of the following neurotransmitters is used in the ganglia of both the sympathetic and parasympathetic nervous system? a) acetylcholine b) dopamine c) norepinephrine d) serotonin

a) acetylcholine

What is NOT considered a higher function of the nervous system? A) motor B) cognition C) emotion D) consciousness

a) motor Higher functions include cognition (thinking), emotions (feelings), consciousness

What are the two main structures of the peripheral nervous system? a) nerves and ganglion b) dorsal root and ventral root c) axons and ganglion d) dorsal root and nerves

a) nerves and ganglion

What are some problems that can occur with motor units?

abnormality can lead to weakness, affect LMN through atrophy, fasciculations (involuntary twitches), hypotonia (decrease muscle tone), hyporeflexia (decrease reflex)

Provide a brief description of the purpose of each of the following: Axon: Axon hillock: Dendrite: Myelin Sheath: Soma: Synaptic button:

axons: transmits electrical signal from soma to axon terminals axon hillock: integrates excitatory and inhibitory signals from the dendrites and fires AP if pass threshold dendrite: receive signals and sends to soma myelin sheath: insulation around the axon and speeds conduction soma: cell body, has neuron, ER, ribosomes synaptic button:releases NT

A surgeon accidentally clips a dorsal root ganglion during a spinal surgery. What is a likely consequence of this error? I. Loss of motor function at that level II. Loss of sensation at that level III. Loss of cognitive function a) I only b) II only c) I and II only d) I, II, and III

b) II only

In which neural structure are ribosomes primarily located? a) dendrites b) soma c) axon hillock d) axon

b)soma

What are the differences between the brain and the spinal cord in terms of white and gray matter?

brain: gray matter is on outside and white is on inside spinal cord: gray matter is on inside while white is on outside

What do the lower motor neurons in the brain control? in the spinal cord?

brain: skeletal muscles in head and neck spinal nerves: muscles in limbs and trunk

What does the brainstem include? I. midbrain II. pons III. medulla A) I and II B) III only C) II and III D) I, II, and III

c) I, II and III The brainstem includes midbrain, pons, and medulla.

Which of the following is not considered the basic functions of the nervous system? a) motor b) automatic c) cognition d) sensory

c) cognition basic functions: motor (skeletal muscle), sensory (the senses), automatic (reflexes)

When a sensory neuron receives a stimulus that brings it to threshold, it will do all of the following EXCEPT: a) become depolarized b) transduce the stimulus c) inhibit the spread of the action potential d) cause the release of NT onto cells in the CNS

c) inhibit the spread of the action potential

Which of the following statements concerning the somatic division of the peripheral NS is INCORRECT? a) its pathway innervate skeletal muscle b) its pathways are usually voluntary c) Some of its pathways are referred to as reflex arcs. d) Its pathway always involve more than 2 neurons

d) Its pathway always involve more than 2 neurons

Which of the following is a function of the parasympathetic nervous system? a) increasing blood sugar during periods of stress b) dilating the pupils to enhance vision c) increasing the oxygen delivery to muscles d) decreasing heart rate and blood pressure

d) decreasing heart rate and blood pressure

Which is the correct association? a) motor neurons and sensory neurons are afferent neurons b) motor neurons are afferent neurons and sensory neurons are efferent neurons c) motor neurons and sensory neurons are efferent neurons d) motor neurons are efferent neurons and sensory neurons are afferent neurons

d) motor neurons are efferent neurons and sensory neurons are afferent neurons

Give an example of the simple reflex arc.

if you pinch your finger, adding pressure will make the pressure receptors create an electrical signal from the stimuli-> signal picked up by the sensory neuron -> CNS (spinal cord) through dorsal side into the gray matter-> synapse into interneuron->synapse onto motor neuron -> effector organ (signal arrives)

Which motor neuron is responsible for controlling skeletal muscle?

lower motor neurons

What kind of neurons are mechanoreceptors and what kind of neurons are nociceptors and thermoreceptors?

mechanoreceptor: afferent nociceptor: afferent thermoreceptors: afferent

What kind of stimuli do each of the receptors respond to? mechanoreceptors: nociceptors: thermoreceptors:

mechanoreceptors: mechanical stimuli like sound, stretch nociceptors: detect pain thermoreceptors: detect temperature

What is the pathway of neural impulses in a monosynaptic reflex? In a polysynaptic reflex?

monosynaptic reflex: an afferent presynaptic sensory neuron fires directly onto a motor efferent postsynaptic neuron. polysynaptic reflex: A sensory neuron may fire directly onto a motor neuron but interneurons are used which fire on other motor neurons

What kind of neurons does the corpus callosum consist of?

myelinated neurons

Fill in the blanks. Muscle cells are made up of _______ which are made up of _______ which contain __________ and _________.

myofibril; sarcomere; actin, myosin

What kind of axons and myelin sheaths are the neurons that detect position, vibration, and some touch and the neurons that detect some touch, pain and temperature?

position, vibration, some touch (fine touch): large diameter axons and thick myelin sheath (faster AP) some touch (less precise touch), pain, temperature: small diameter axons, thin myelin sheath or no myelin sheath

What are the 5 types of somatosensation?

position, vibration, touch, pain, temperature

How does the somatic nervous system differ from the autonomic nervous system?

somatic: controls voluntary movement

Explain the difference of the signal path of the sympathetic and parasympathetic NS.

sympathetic: the first neuron (preganglionic neuron)has short neuron starting from spinal cord and synapses on second neuron (postganglionic neuron) with Ach release which extends until the effector where it releases NE/E parasympathetic: the first neuron (preganglionic neuron) (begins in brain or spinal cord) has a long neuron and extends closer to effector and synapses with Ach release on the short second neuron (postganglionic neuron) which releases Ach into effector

List the structures that are in each of the following: telencephalon: diencephalon: metencephalon:

telencephalon: cerebrum, hippocampus, basal ganglia diencephalon: hypothalamus and thalamus metencephalon: cerebellum and pons myelencephalon: medulla

What are axons that travel together with the same function known as?

tracts