Learner Resource 1 - The nervous system, neurons, and synapsesFill in the gaps to complete the summary sheet and then use the key terminology to label the neuron and synapse.

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SynapseThe point where one neuron

to another neuron is called the synaptic

connection. At this point there is a small

called the synapse.

Synapses send electrical impulses to

neighbouring neurons. At the synapse,

are released which will

either have an excitatory or

effect on the next

neuron. Excitatory potentials increase the

chance of a neuron firing. Inhibitory potentials

decrease the chance of a neuron firing.

The nervous systemThe human nervous system is a complex network

of to and from the brain.

The Nervous System has two main parts. The

system and the Peripheral Nervous System. The

central nervous system consists of the

and the spinal cord. The brain is within the skull

and the spinal cord is within the

The peripheral nervous system is made up of the

Autonomic Nervous System and the

………………… . System.

The automatic nervous system is responsible for

vital functions and autonomic processes, like

breathing, digestion, stress responses. The

somatic nervous system controls

movement and receives

sensory information.

Words to help you fill in the blanks

Motor Synaptic buttons Vertebrae Electrical impulses Muscle

Nerve cells Neurotransmitters Brain Gap Axon

Somatic Nervous Inhibitory dendrite central nervous connects

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NeuronsA neuron is a nerve cell and the primary functioning unit of the nervous system. They are adapted to carry ……………………. ……………………….from

one place to another. There are around 10 to 12 billion neurons in the brain. There are three main types of neurons, sensory, relay and …………………..…

neurons. The cellular structure of each is very similar. A ……………………is the area of a neuron which receives most information, receptors on dendrites

pick up signals from other neurons, which come from chemicals called neurotransmitters. Neurotransmitters are interpreted in an area called the soma

(cell body). The Soma contains the nucleus of a neuron which contains the DNA of the cell. If signals from dendrites are strong enough then the signal is

sent to the next part of the neuron called the………………….. At this point the signal is called the action potential. The action potential travels down the

axon which is covered in myelin (an insulating material that helps to prevent the signal from degrading). The last step for the action potential is the axon

terminals also known as……………………. ……………………….. When the signal reaches the axon terminals it can cause the release of

neurotransmitters. When a neurotransmitter is released from axon terminals it interacts with the dendrites on the next neuron and the process repeats.

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