Nervous System
Two types:
1. Central Nervous system:
a. responsible for integrating, processing and coordinating sensory data and motor commands;
b. issues orders to organs, muscles and glands.
2. Peripheral Nervous System:
a. transmits information to and from CNS.
b. Controls movements and responses.
c. It is a physical extension of the central nervous system (CNS).
, Central Nervous System
● Brain
● Spinal cord: bridge between brain and peripheral nerves.
Peripheral Nervous System
● Somatic Nervous System:
o controls skeletal muscles
● Autonomic Nervous System:
o regulates glands, blood vessels,
o internal organs- reproduction, gut digestion, secretion of enzymes etc,
o blood vessels dilation therefore controlling heart rate, therefore controlling how much
oxygen we obtain.
Autonomic splits into two
1. Sympathetic Nervous System: mobilises the body for action, energy output.
2. Parasympathetic Nervous System: conserves energy, maintains a quiet state.
Cells- Neurones and Glia
Neurones are composed of:
● Cell body
o contains the nucleus, the location of the genetic material and synthetic activity of
the neuron.
● Dendrites
o shrub like extensions from the cell body
o receive incoming information from other neurones,
▪ allows their function to be modulated by inputs from many different
sources
● Axon
o conducts information collected by the dendrites and cell body away from the cell
by electrical signals called action potentials.
▪ can be very long-can transmit info along large distances of the body.
There are two main types of neurones:
1. Multipolar motor neurones:
● have two or more dendrites
● single axon that may have one or more collateral branches.
● Most abundant
All motor neurones that control skeletal muscle and those comprising the ANS are multipolar neurones.
2. Pseudounipolar sensory neurones:
● Short, apparently single (but actually double) process extending from cell body.
● This common process separates into a peripheral process, conducting impulses from the
receptor organ (touch, pain or temp sensors in the skin for example towards the cell body
and a central process that continues from the cell body into the CNS.
● Cell bodies are located outside the CNS in sensory ganglia and therefore part of the PNs
Two types:
1. Central Nervous system:
a. responsible for integrating, processing and coordinating sensory data and motor commands;
b. issues orders to organs, muscles and glands.
2. Peripheral Nervous System:
a. transmits information to and from CNS.
b. Controls movements and responses.
c. It is a physical extension of the central nervous system (CNS).
, Central Nervous System
● Brain
● Spinal cord: bridge between brain and peripheral nerves.
Peripheral Nervous System
● Somatic Nervous System:
o controls skeletal muscles
● Autonomic Nervous System:
o regulates glands, blood vessels,
o internal organs- reproduction, gut digestion, secretion of enzymes etc,
o blood vessels dilation therefore controlling heart rate, therefore controlling how much
oxygen we obtain.
Autonomic splits into two
1. Sympathetic Nervous System: mobilises the body for action, energy output.
2. Parasympathetic Nervous System: conserves energy, maintains a quiet state.
Cells- Neurones and Glia
Neurones are composed of:
● Cell body
o contains the nucleus, the location of the genetic material and synthetic activity of
the neuron.
● Dendrites
o shrub like extensions from the cell body
o receive incoming information from other neurones,
▪ allows their function to be modulated by inputs from many different
sources
● Axon
o conducts information collected by the dendrites and cell body away from the cell
by electrical signals called action potentials.
▪ can be very long-can transmit info along large distances of the body.
There are two main types of neurones:
1. Multipolar motor neurones:
● have two or more dendrites
● single axon that may have one or more collateral branches.
● Most abundant
All motor neurones that control skeletal muscle and those comprising the ANS are multipolar neurones.
2. Pseudounipolar sensory neurones:
● Short, apparently single (but actually double) process extending from cell body.
● This common process separates into a peripheral process, conducting impulses from the
receptor organ (touch, pain or temp sensors in the skin for example towards the cell body
and a central process that continues from the cell body into the CNS.
● Cell bodies are located outside the CNS in sensory ganglia and therefore part of the PNs
