Biology bsc

1. CHAPTER# 12 COORDINATION AND CONTROL
TOPIC: TYPES OF COORDINATION
HUMAN NERVOUS SYSTEM
SESSION:2020/2021
TEACHER:MS NOOR FATIMA

2. At the end of lesson student will be able to :
Define the component of a coordinated action.
Define nerve cell its structure and different parts of
nerve cell.
Three different types of neuron.
Define nerve and its types.
;

3. Coordination means the working of body as one
unit, by cooperation of different body organs and
system in harmony with each other.

4. COORDINATION AND CONTROL
 EXAMPLE:
 When a boy runs to catch a ball he
uses hundreds of muscles to move
his arms , legs and back. His
nervous system uses information
from his sense organs and
breathing and heartbeat rate is
increased extra heat is removed
from body etc.

5. Types of coordination
Nervous coordination…….nervous system
Chemical coordination……endocrine system

6. A coordinated action has five components.
•Stimuli
•Receptor
•Coordinators
•Effectors
•response

7. STIMULI:
Any change in environment(external or internal)
which can provoke a response in organism.
Example:
light, heat, cold, pressure, sound waves etc
RECEPTORS:
The organs tissues or cells which detect a
particular type of stimuli are called receptors.
Example:
ears, eyes, nose, skin etc.
COORDINATORS:
The organs that receive information from
receptors and send messages to particular organs for proper
action.
Example:
brain and spinal cord in nervous coordination
endocrine gland in chemical coordination

8. EFFECTOR:
The parts of body which receive messages from
coordinators and produce particular responses.
Example:
muscles and gland
RESPONSE:
The action performed by effectors after receiving
message from coordinators.
Example:
I. pulling hand away from hot object.
II. the movement of sunflower towards light.

9. COORDINATION AND CONTROL

10. COORDINATION AND CONTROL
nervous coordination chemical coordination

11. HUMANNERVOUS SYSTEM:
It is composed of two major
components.
1. Central nervous system
 Brain
 Spinal cord
2. Peripheral nervous system

12. COORDINATION AND CONTROL
 NERVE CELL / NEURON:
Nerve cell or neuron is the unit of the nervous
system.
Neuron are specialized cells that are able to
conduct nerve impulses from receptors to
coordinators and from coordinators to effectors.

13. PARTS OF NEURON

14. PARTS OF NEURON
 SCHWANN CELLS:
 Special cells located at regular
interval along axon.
 MYELIN SHEATH:
 Schwann cells secrete a fatty layer
called myelin sheath.
 NODES OF RANVIER:
 Between the area of myelin on an
axon there are non myelinated
points called the nodes of Ranvier.


15. TYPES OF NEURON
 There are three types of neuron on the basis of
their functions.
 SENSORY NEURONS:
• Conduct sensory information from receptors
towards the CNS.
• sensory neurons have one dendrite and one axon.

16. INTER NEURON:
Inter neuron form brain and spinal cord.
They receive information, interpret them and stimulate
motor neurons.
They have many dendrites and axon.

17. MOTOR NEURONE:
They carry information from inter neurons to muscles
(effectors).
They have many dendrites but only one axon.

18. TYPES OF NEURONS

19. TYPES OF NEURON

20. NERVE:
The union of several axons that are enveloped
by a covering made of lipids.
There are three types of nerves.
Sensory nerves contain the axon of sensory
neurons only.
Motor nerves contain the axon of motor
neurons only.
Mixed nerves contain the axons of both i.e
sensory and motor neurons.

21. HOME ASSIGNMENT
What are the main component of coordination?
Define neuron and describe the structure of a
general neuron.
Write different types of neuron on the basis of
their function.
Define nerve and types of nerves.