Introduction to nervous system

Question 1

3 parts of brain

Answer 1

Forebrain (Cerebrum[telencephalon], Diencephalon
Midbrain
Hindbrain (Pons, Medulla Oblongata, Cerebellum

Question 2

Segments of spinal cord, how many spinal nerves are there

Answer 2

Cervical (C8)
Thoracic (T12)
Lumbar (L5)
Sacral (S5)
Coccygeal

Question 3

12 pairs of cranial nerves

Answer 3

Olfactory nerve (i)
Optic nerve (ii)
Oculomotor nerve (iii)
Trochlear nerve (iv)
Trigeminal nerve (v)
Abducens nerve (vi)
Facial nerve (vii)
Vestibulocochlear nerve (viii)
Glossopharyngeal nerve (ix)
Vagus nerve (x)
Accessory nerve (xi)
Hypoglossal nerve (xii)

Question 4

Structural classification of nervous
system

Answer 4

The nervous system is divided into two parts:
Central nervous system (CNS)
It consists of brain and spinal cord
Peripheral nervous system (PNS)
It consists of cranial nerves, spinal nerves and their
associated ganglion. There are 12 pairs of cranial
nerves and 31 pairs of spinal nerves

Question 5

Functional classification of nervous
system

Answer 5

Somatic nervous system
Autonomic nervous system

Question 6

Cells of nervous tissue

Answer 6

Neurons which are excitable cells responsible for
conduction of nerve impulse
Neuroglia which are supporting cells and provides
structural, nutritional and protective support to
neurons. They are non excitable and non
conducting.

Question 7

Morphological classification of neurons

Answer 7

According to the number of cell processes
According to the length of their axons

Question 8

Classification of neurons according to the number of cell processes

Answer 8

Unipolar neurons are those in which only one cytoplasmic process arises from the cell body, which soon divides into dendrite and
axon. Example ; neuron in the posterior root ganglion.
Bipolar neurons are those in which two cytoplasmic processes arise from the cell body, one of which is dendrite and the other one is axon. Examples; neuron in the retinal bipolar cells, cells of
the sensory cochlear
Multipolar neurons have a number of cytoplasmic processes arising from the cell body . Usually the long process is the axon, the remainder are dendrites. Most neurons of the brain and spinal cord are of this type.

Question 9

Classification of neurons according to the length
of their axons

Answer 9

Golgi type I neurons have a long axon. Their
fibers pass to other regions of nervous system. For example the pyramidal cells of the cerebral cortex

Golgi type II neurons have a short axon. Their
fibers remain within the same region of nervous
system. These neurons are numerous in the
cerebral and cerebellar cortex.

Question 10

Functional classification of neurons

Answer 10

Sensory neurons receives sensory information
from environment and pass them to CNS
Motor neuron convey impulse to effector
organs such as muscles and glands from CNS.
Interneurons. They connect different neurons
to form complex functional circuit.