Nervous system
- Divisions of the nervous system
- The brain
In which form is the message carried by the sensory
By nerve impulses
and the motor pathways?
MOTOR
NEURON
SENSORY
NEURON
RECEPTORS
What
2 types of effectors
are there?
Muscles
EFFECTOR Glands
What is the result of their
Contraction
Secretion
stimulation?
The nervous system analyses sensory
information from the
1
body
environment
2 and the external
3
The information is analysed and appropriate voluntary and
involuntary motor responses
are made which lead to
4
muscular contractions
or glandular secretions
5
6
7
Some of the information is stored
for future use.
What is the function of sensory neurons?
Carry impulses from receptors to the CNS.
What is the function of motor neurons?
Carry impulses from the CNS to effectors.
Structural division of the nervous system
NERVOUS SYSTEM
CENTRAL
NERVOUS SYSTEM
BRAIN
SPINAL
CORD
PERIPHERAL
NERVOUS SYSTEM
• In which 2 parts can the peripheral nervous system
be divided in?
• Somatic Nervous System (SNS)
• Autonomic Nervous System (ANS)
• What is the function of the Somatic NS?
• Sensory and motor neurones of the somatic
nervous system (SNS) control the mostly voluntary
movement of skeletal muscles.
• Example of functions controlled by the Somatic NS?
• Walking and speaking
• What is the function of the Autonomic NS?
• To regulate the internal environment by the
involuntary control of the heart, alimentary canal,
blood vessels and bronchioles.
• What is the name given to the maintenance of the
body’s internal environment within certain
tolerable limits despite changes in the body’s
external environment?
• Homeostasis
• In which 2 parts can the autonomic nervous system
be divided in?
• Sympathetic Nervous System (SNS)
• Parasympathetic Nervous System (PNS)
• These two systems affect many of the
__________structures
but have __________effect
opposite
same
on them.
antagonistic
• They are said to be______________.
• In broad terms, homeostatic control is through
sensory neurons and motor neurons
conducting involuntary impulses to what?
• Smooth muscle, cardiac muscle and glands.
• Sympathetic NS:
• Effect on cardiac muscle?
• Increased rate and force of contractions result in
increased cardiac output
• Effect on smooth muscle of the walls of the
digestive system?
• Decreased rate of peristalsis
• Effect on smooth muscles in wall of bronchioles?
• Tube bore dilates resulting in an increased
volume of air to enter lungs
• Effect on adrenal gland?
• Increased rate of secretion of adrenaline
• Parasympathetic NS:
• Effect on cardiac muscle?
• Decreased rate and force of contractions result in
decrease cardiac output
• Effect on smooth muscle of the walls of the
digestive system?
• increased rate of peristalsis
• Effect on smooth muscles in wall of bronchioles?
• Tube bore constrict resulting in a decreased
volume of air to enter lungs
• Effect on adrenal gland?
• No effect- no