1. SBI4U Nervous System

2. The Division of Nervous System The nervous system is divided into to functional subsystems : 1- The Central Nervous System (CNS) 2- Peripheral Nervous System (PNS) A specialized nerve cell is called a neuron

3. Neuronal Signalling Neuronal signalling or communication between neurons include 3 types of neurons: 1- Afferent neurons 2- Interneurons 3- Efferent neurons Processing of information in the nervous system involves 5 steps: Reception  Transmission  Integration  transmission  response

4. Anatomy of neuron

6. Reflex arc

7. Structure Function Neuron Afferent Neuron Interneuron Efferent Neuron Dendrite Axon Myelin Sheath

8. Structure Function NeuronConducts nerve impulses Afferent NeuronCarries impulses to central nervous system InterneuronCarries impulses within the central nervous system Efferent NeuronCarries impulses from the CNS to effector DendriteProjection of cytoplasm carries impulses towards cell body AxonExtension of cytoplasm carries impulses away from cell body Myelin SheathInsulated covering of axon Composed of schwann cells

9. Q1) Differentiate between CNS and PNS. Q2) What are the 5 essential components of reflex arc

10. Q1) CNS: brain + spinal cord. CNS serves as the coordinating centre for incoming and outgoing information PNS: carries information between the organs of the body and CNS Q2) Refelex arc has 5 essential components: the receptor (receives impulse), sensory neuron (detects the stimulus), Interneuron (transfers the impulse), Motor neuron (relays the impulse to proper effector), Effector (acts on impulse).