Topic 7: The Structural and Functional Organization of the Nervous System

The simplest neuronal network is what?

The Reflex Arc

The simplest reflex arc existing today is found in the well-studied nematode _____________.

Caenorhabditis elegans

True or False: Monosynaptic Reflex Arc consists of a sensory neuron and a motor neuron.

True

________ Reflex Arcs involve three or more neurons and two or

more synapses.

Polysynaptic

In the case of mixed nerves the neuronal axons composing a nerve organ subunit called a __________ will all be of the same functional type.

Fascicle

Perikarya located in the PNS are located in aggregates called what?

Ganglia

What allows the CNS to carry out different operations on one set of information simultaneously.

Parallel Processing (Information may be carried from one neuron to more than one postsynaptic neuron allowing for divergence.)

Studies have shown that evolution has been very _________in regards to the principal neurotransmitters of the nervous system.

conservative

What are the simplest nervous systems anatomically.

Nerve Nets

Where are Nerve Nets found?

cnidarians

Information is exchanged between ganglia by connecting nerve trunks called what?

Connectives

Annelids and Arthropods have developed a _______ Nerve Cord from these ganglia and connectives.

Ventral

In many animals, and especially in vertebrates, higher regions of the brain will develop _______, body mapping.

Somatotopy

the Motor Division can be divided into the _______ Motor and ______ Motor subdivisions.

Somatic, Visceral

The spinal cord serves to connect the ____ and the brain.

PNS

The spinal cord begin where it meets the ________ at the level of the foramen magnum.

medulla oblongata

The end of the spinal cord is a tapering structure called what?

Conus Medullaris

Numerous spinal nerves will arise from the conus medullaris. They form what?

the Cauda Equina

The gray matter is primarily composed of ________ axons, dendrites, and perikarya.

unmyelinated

The _____ matter is surrounded by _____ matter in the spinal cord and in turn encloses the central canal.

gray, white

What connects the two halves of gray matter.It is like the bar on an H.

The Gray Commissure

What horns are composed of interneurons receiving sensory information from the PNS.

the Posterior or Dorsal Horns

The dorsal horns process _______information.

sensory

What horns have the cell bodies of motor neurons whose axons are extending out towards the effector organs

Anterior or Ventral Horns

The ventral horns process ______ information.

motor

Spinal cord white matter is primarily composed of what?

myelinated axons.

Type of Tract: Most carry sensory information from the receptors to the brain.

Ascending Tracts

Type of Tract: Most carry motor information from the brain to the effector organs.

Descending Tracts

Type of Tract: These tracts carry information from one side of the spinal cord to the other.

Commissural Tracts

Ventral Roots carry ______ information from the spinal to the body.

motor

Dorsal Roots carry ______ information into the spinal cord from receptor organs.

sensory

What is the caudalmost portion of the brain and is a portion of the “brain stem”.

Medulla Oblongata

What is responsible for the gracefulness and coordination of somatic motor activities?

The Cerebellum

What contains the perikarya of certain cranial nerves, ganglia for automatically controlled behaviors, and axons traveling to and from the cerebrum?

The Pons

What contains the perikarya of certain cranial nerves, ganglia for rigid automatically controlled behaviors, and axons traveling to and from the cerebrum?

The Midbrain

The midbrain, pons, and medulla oblongata make up the ____________ which is responsible for rigid automatically controlled behaviors.

Reticular Formation

The diencephalon and cerebrum comprise what?

forebrain

Diencephalon subdivision: the main relay center between the cerebrum and the rest of the CNS.

Thalamus

Diencephalon subdivision: Located dorsal to the thalamus this region includes an endocrine organ called the Pineal Gland.

Epithalamus

Diencephalon subdivision: Epithalamus is located dorsal to the thalamus and this region includes an endocrine organ called what?.

The Pineal Gland

Diencephalon subdivision: Located ventral to the thalamus

Hypothalamus

What is the main visceral control center of the body

Hypothalamus

the hypothalamus works in coordination with a cerebral nucleus called what?

Amygdala

The cerebrum is the portion of the brain that shows the _______ degree of variation between vertebrate classes and families.

greatest

Cerebrum: The central core of white matter, termed ________ White Matter, consists of axons traveling to and from the outer cerebral layer.

Cerebral

In mammals there will be clusters of grey matter within the cerebral white matter called what?

basal nuclei

Cerebrum: In mammals it is a highly convoluted layer of perikarya called what?

the Neocortex or Cerebral Cortex.

The mammalian cebral cortex will be arranged into _________ of specialized functioning (ex; Motor Cortex).

Domains

Which nervous system controls the visceral organ musculature and glands?

The Autonomic Nervous System (ANS)

The ________ nerve is a myelinated nerve which arises from the CNS and sends ANS information towards the ANS ganglion.

preganglionic

Neuron relay system: The preganglionic neuron uses what neurotransmitter?

Acetylcholine

The __________ nerve is an unmyelinated nerve which arises from the ANS ganglion and send ANS information tow the target organ.

postganglionic

The sympathetic division uses _________ (adrenaline and noradrenaline) to communicate between the postganglionic nerve and the target organ.

Epinephrine and Norepinepherine

Which ANS division is Adrenergic?

Sympathetic

The parasympathetic division uses _________ to communicate between the postganglionic nerve and the target organ.

Acetylcholine

Which ANS division is Cholinergic?

Parasympathetic

The ________ division causes the “flight, fright, and fight” response.

sympathetic

The origin of the sympathetic division is said to be what?

Thoracolumbar

What are paired structures located parallel to the vertebral column.

Chain Ganglia

The chain ganglia on one side are linked by nerve trunks to form what?

A Sympathetic Trunk

What are singular structures located ventral to the vertebral column.

Prevetebral Ganglia

What is the central portion of the adrenal gland, is actually a sympathetic ganglion.

Adrenal Medulla

The parasympathetic division is sometimes called what?

the “housekeeping division”

What causes a decrease in heart rate, breathing rate, and an increase in blood flow to the digestive and excretory organs.

Parasympathetic Division

The Parasympathetic Division arises from the cranial nerves and the ______ spinal nerves.

sacral

The Parasympathetic Division origin is said to be what?

Craniosacral

The parasympathetic ganglia are located near or in what?

The target organs

In cases where organs are innervated by both divisions, the organ receives sympathetic innervation and the opposite effect is achieved through what?

Sympathetic Suppression