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1. Label the structure of an efferent neurone (pg80)

2. Identify types of neurone from the diagramsgiven (pg 80)

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3. State the function of each type of neurone

- Afferent neurone : carries nerve impulses from the

receptor to the brain and spinal cord- Interneurone : carries nerve impulses from an afferent

neurone to an efferent neurone

- Efferent neurone : carries nerve impulses from thebrain and spinal cord to the effectors such as themuscles and glands which carry out the response.

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4. State the mode of transmission of information along aneurone

-Neurones transmit information in the form of electricalsignals called nerve impulses.

- All nerve impulses travel in the same direction withina neurone.

- Nerve impulses begins in the dendrites of a neuroneand travels rapidly towards the cell body and thendown the axon towards the axon terminals/synapticterminals.

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5. Describe briefly the pathway of transmission ofinformation from the receptors to the effectors

(Figure 3.11, page 82)

6. Draw and label a simple diagram of a synapse

(Figure 3.13, page 84)

-synapse : a site where the two neurones or a neuroneand an effector cell communicate. Its a narrow gap.

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7. Describe the transmission of information across asynapse

- Nerve impulses cannot pass through the synapse.

- Chemicals called neurotransmitters are released intothe synapse, enabling the nerve impulse to cross thesynapse.

- The axon terminal has a swollen part called synaptic

knob/synaptic terminal which contain vesicles filledwith neurotransmitters.

- When an impulse arrives at the synaptic terminal, thevesicles release neurotransmitters into the synapse.

- Neurotransmitters molecules diffuse across thesynapse to the dendrite of another neurone.

- The dendrite is stimulated to trigger a new impulsewith travels down along the neurone.

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8. State the role of the synapse in the transmission ofinformation

- Synapse transmit information between neurones.

9. Give examples of voluntary action

10. Give examples of involuntary action

Revision : Part of brain that controls voluntary action : ?

Part of brain that controls involuntary action : ?

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11. Outline the transmission of the information involuntary action

Stimulus -> Receptor -> Brain (?) -> Effectors ->Response

12. Outline the transmission of the information in the

involuntary actionStimulus -> Receptor -> Medulla Oblongata -> Effectors-> Response

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13. Draw a schematic diagram showing a reflex arc.

-Reflex action is an automatic response that occurs

rapidly and without any conscious control.- It is involuntary action that involves the contraction of

the skeletal muscles and the spinal cord only.

- The pathway along which an impulse travels from a

receptor to the effector is called the reflex arc.- Schematic diagram (Figure 3.15, page 86)

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14. Give examples of nervous system-related disease

a. Alzheimers disease : neurological diseasecharacterised by increasing loss of memory andintellectual ability. It is associated with shrinkage ofbrain tissues and lack of neurotransmitters.

b. Parkinsons disease : it causes tremors and weaknessof the muscles. It is due to the reduced level ofneurotransmitters in the brain.

Any question? Question that not answering theobjectives of the lesson, you can go back home andgoggle it yourself