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N E W R O N

N E U R O N

6.5 Nerves

Homework

6.5.1 State that the nervous system consists of the central nervous system (CNS) and peripheral nerves, and is composed of cells called neurons that can carry rapid electrical impulses.

6.5.2 Draw and label the structure of a motor neuron, include;

dendrites, cell body with nucleus, axon, myelin sheath, nodes of Ranvier, motor end plates.

6.5.3 State that nerve impulses are conducted from receptors to the CNS by sensory neurons, within the CNS by relay neurons, and from the CNS to effectors by motor neurons.

1. Central nervous system

2. Peripheral nervous system

3. Stimulus

4. Receptor

5. Central nervous system

6. Motor neuron

7. Effector

8. Response

Outcome To understand how and why animals

respond to their environment

What is it made of?

Central Nervous System (CNS)Neurons in the brain and spinal chord.Peripheral Nervous System (PNS)Neurons connecting the brain and spinal chord to the body. (Motor & sensory neurones)

http://www.bbc.co.uk/schools/gcsebitesize/science/aqa/human/thenervoussystemact.shtml -

TASK:Label the CNS and PNS:

Key Facts

When neurons are stimulated they send rapid electric impulses. Super fast messages. Gaps between neurones: synapses Impulses travel from one neuron to another across synapses .

There are hundreds of types!

Remember:Remember: aaxonsxons take impulses take impulses aawayway from from cell bodies.cell bodies.

LO1: Describe the structure of neurons LO2: Relate the structure of neurons to their function

Task Annotate the diagram: link STRUCTURE to

FUNCTION. 1. Long axon (cytoplasm extension) to send electrical impulses

from central nervous system to motor neuron.2. Myelin sheath insulates the axon, speeding-up

transmission of electrical impulses.3. Arrow to show the direction of the nerve impulse.4. Node of ranvier, a periodic gap in the myelin sheath5. Cell body/nucleus (axon hillock) which integrates signals6. Motor end plate which transmit impulses across synapses

to other neurons

EXT Label one place at either end of the neuron where you would expect to find a synapse (gap between two neurons which communicate)

Check and add to your answers:

Motor end plates

Myelin Sheath

Long Axon

Direction of impulse

Cell bodyNucleus (axon

hillock)

6. Neuron endings: All neuron endings will have synapses to connect to other

neurons and send messages

6. Connections to cell body will have incoming

synapses.

Node of ranvier

TouchPressure

and temperatu

re

Smell

HearingSound and

BalanceSightLight

Tongue Taste

Collect info and send it to sensory neuronsReceptors can be part of organs, like the eye.

Neurons : SRM

Label the diagram to show how he responds and survives, including PNS, CNS and names of each parts of the circuit

Car comes towards man in daylight

https://www.youtube.com/watch?v=OdOOIxcUjAs

PNS

Relay in

CNS PNS

1. What two things make up the central nervous system?

2. What is a receptor? Explain and give an example.

3. What is an effector? Explain and give an example.

4. Why do animals need to respond to stimulus?

Ext: Give an example of an animal responding to a stimulus: give examples of stimulus, receptor, CNS, effector and response. (Draw a flow map if its easier)

Brain and spinal chord

Something that causes a response. Receives message from motor neurone and causes muscle/gland response.

To survive / Avoid horrible painful deaths.

HeatTemperature receptor in skin relay neurone in CNS Effector = Muscle Response = Movement away from heat

Something that receives information. Receptors in the ear receive sound.

Stimulus Receptor Sensory Neuron Relay Neuron

Motor Neuron Effector Response

Stimulus – bright light in eyes

Response – raise hand to shield eyes