PP3 - Nothing to become nervous about! The Nervous System
How do we control our body? All of the systems in your body are controlled by the nervous and endocrine systems. We use these systems to: Move Digest food Breathe Think Talk + much more
The Nervous System Can be split into two groups: Central Nervous System (CNS) Brain Spinal cord Peripheral Nervous System (PNS) - Nerves (made of bundles of neurons) Get students to copy down this slide Copy down this information in your books
Central Nervous System- Brain The brain is the main organ of the nervous system. It controls the actions of the nervous AND endocrine system. There are three main parts: Cerebrum Cerebellum Brain stem
A representation of the brain Which side of the brain do you think this picture shows us? The front The left side The back The right side Draw a quick sketch of the brain AND label: The cerebrum The cerebellum The brain stem
The Cerebrum Is the largest part of the brain Responsible for: Memory Speech Voluntary action Conscious thought.. (What is conscious thought?)
The Cerebellum Is the small part of the brain at the back of your head Responsible for: Balance Coordination Involuntary muscular activity What might happen if you had a damaged cerebellum and you rode a bike?
The Brain Stem Located at the base of the brain Responsible for: Involuntary actions e.g Breathing, heart beat and digestion The Respiratory System The Circulatory System The Digestive System
The Spinal Cord Pathway to the brain from sensory neurons Pathway away from the brain to motor neurons
Peripheral Nervous System Includes all other nervous system structures outside of the CNS e.g Nerves (made up of neurons) Connects all areas of the body to the CNS
Neurons Neurons are the longest cells in our bodies. Communicate with eachother and pass messages along to other neurons. Electrical nerve impulses travel along them in only ONE DIRECTION. To assist you in remembering
Types of Neurons Sensory neurons Send nerve impulses to the brain from receptors (sense organs) Motor neurons - Send nerve impulses from the brain to the muscles or glands
Sensory Neuron (Afferent)
Motor Neuron (Efferent)
Class task Draw a labelled picture of: A sensory neuron A motor neuron Make sure to include: 1) An arrow showing the direction of nerve impulse. 2) Labels for the axon, cell body and myelin sheath Ask a student/students to come draw on the whiteboard.
HOW DOES IT ALL WORK? RESPONSE Contraction of the skeletal muscles, more commonly known as shivering, is the body’s response to low body temperature.
Reflex Arc Sometimes referred to as the reflex loop or a reflex action. Very fast response to a stimulus Can be thought of as a ‘short cut’ https://www.youtube.com/watch?v=Di5kblvpmiM Why do you think we have the reflex arc? What purpose does it serve?
Representation of the reflex arc
Interesting Facts The left side of your brain controls the right side of your body and the right side of your brain controls the left side of your body. There are more nerve cells in the human brain than there are stars in the Milky Way. Sea sponges have no nervous system
Crash Course Biology https://www.youtube.com/watch?v=x4PPZCLnVkA If you liked this video and are interested in seeing more, type in “Crash course” into YouTube. Videos look at biology, psychology and history.