Nervous Tissue
Thursday, 17th February 2022
Nervous tissue is specialised to conduct
electrical impulses from one part of the
body to another.
The CNS is where most of the
nervous tissue is located and
encompasses the brain and spinal
cord and coordinates responses.
The PNS is the collection of many
smaller nerves that branch off of our
CNS and circulate through the body
transmitting signals.
The peripheral and central nervous
systems.
The two cells that make up nervous tissue are the:
Neurones which include sensory neurones activated by sensory inputs
(afferent neurones are sensory but carry messages to the CNS) and motor
neurones which are in the CNS which project their axons into muscles or
glands (effectors).
Neuroglia assist the neurones and provide mechanical and metabolic
support, however they do not transmit signals or impulses.
Neurons:
Typical neurones consist of the cell body or soma where dendrites extend out of
the soma as projections to receive information and then axons which send
information (conduct nerve impulses away from soma) to other dendrites.
Nervous Tissue 1
, The cell body performs all regulatory functions, while the Schwann cells
(made of lipids) act as insulators for the axons, which can extend to great
lengths.
Structure of a (multipolar) neurone.
The cell body has a large body and a prominent nucleolus and has the main
concentration of organelles. The dendrites and axon are cytoplasmic extensions
of the cell body.
There are four types of
neurones based on
structure...
1. Anaxonic neurones
have no
distinguishable
axons or dendrites
The four types of neurones by structure.
and are found in the
brain.
2. Unipolar neurones
have the axon and
dendrites fused and
the cell body is
Nervous Tissue 2
Thursday, 17th February 2022
Nervous tissue is specialised to conduct
electrical impulses from one part of the
body to another.
The CNS is where most of the
nervous tissue is located and
encompasses the brain and spinal
cord and coordinates responses.
The PNS is the collection of many
smaller nerves that branch off of our
CNS and circulate through the body
transmitting signals.
The peripheral and central nervous
systems.
The two cells that make up nervous tissue are the:
Neurones which include sensory neurones activated by sensory inputs
(afferent neurones are sensory but carry messages to the CNS) and motor
neurones which are in the CNS which project their axons into muscles or
glands (effectors).
Neuroglia assist the neurones and provide mechanical and metabolic
support, however they do not transmit signals or impulses.
Neurons:
Typical neurones consist of the cell body or soma where dendrites extend out of
the soma as projections to receive information and then axons which send
information (conduct nerve impulses away from soma) to other dendrites.
Nervous Tissue 1
, The cell body performs all regulatory functions, while the Schwann cells
(made of lipids) act as insulators for the axons, which can extend to great
lengths.
Structure of a (multipolar) neurone.
The cell body has a large body and a prominent nucleolus and has the main
concentration of organelles. The dendrites and axon are cytoplasmic extensions
of the cell body.
There are four types of
neurones based on
structure...
1. Anaxonic neurones
have no
distinguishable
axons or dendrites
The four types of neurones by structure.
and are found in the
brain.
2. Unipolar neurones
have the axon and
dendrites fused and
the cell body is
Nervous Tissue 2
