1. GREEN
WHITE
PURPLE
BLUE
RED
PINK
ORANGE
YELLOW
GREY
BLACK

2. GREEN
WHITE
PURPLE
BLUE
RED
PINK
ORANGE
YELLOW
GREY
BLACK

5. Which circle is not round?
They all are

6. The Nervous System

7. Two Divisions of the Nervous System:
Central nervous system (CNS) = the brain and spinal cord
Function: controls behavior
Peripheral nervous system (PNS) = a vast network of nerves that conduct impulses between the CNS and the receptors and effectors of the body (via sensory & motor neurons)
Function: responds to the world around you

8. Stimulus, Receptor, Impulse, Effector
stimulus = something that causes a receptor to trigger impulses in a nerve pathway
receptor = specialized sensing cells that respond to a particular type of stimulus
impulse = message carried by the nerve cells
effector = a muscle or gland that responds to a particular stimulus

10. The Neuron – aka Nerve Cell
Types of Neurons:
sensory neuron = carries impulses from receptors → spinal cord and brain
interneuron = relay impulses from each neuron in brain and spinal column
motor neuron = carries responses from spinal cord/brain → effectors (muscles)
Note: Nerves are bundles of axons or dendrites that are bound together by connective tissues

11. Organization of the Nervous System

12. Types of Neurons
Activity idea – stuffed animal – place pipe cleaner neurons on it with

13. Parts of a Neuron:
Dendrites = pick up impulses (from receptors or other neurons) → conducts impulse to cell body
Cell Body = integrates signal, coordinates metabolic activities
Axon = carries impulse away to other neurons/cells
Note: The direction of an impulse always travels from the dendrites → axons

14. Myelin Sheath = white, fatty, protein that insulates the axon and prevents the loss of chemical ions (necessary for transmission of impulse)
- forms when Schwann cells wrap themselves around an axon
Nodes of Ranvier = gaps on myelinated axons (not covered by the sheath)

15. Myelin Sheath

16. Note: enzymes will stop the transmission of the signal
Synaptic terminals = A bulb at the end of an axon in which neurotransmitter molecules are stored and released
Used to transmit signals to other neurons
Note:
there is no contact b/w two neurons
no electrical impulse can pass through them
there is a microscopic space b/w neurons → synapse
there are chemicals (neurotransmitters) that are used to signal the next neuron
Note: enzymes will stop the transmission of the signal

17. Synapse Structure

18. - allows potassium/sodium ions to move freely across membrane
Nerve Impulse
When a nerve cell is at rest (not stimulated) → polarized (negative charges inside and positive charges outside the neuron)
- allows potassium/sodium ions to move freely across membrane
Depolarized region = when a stimulus passes through the neuron changing the polarity (negative charges on the outside and positive charges on the inside)
Repolarization = restores resting position (negative charges inside/positive outside)
Do demonstration – the ‘wave’ through a chain of arms
Someone will run with them showing the area of –ve transmission

19. Direction of Impulse + + + + + + + + - - - - - - - - - - - - - - - - +

20. Direction of Impulse K+ Na+ + + + - - + + + - - - + + - - - - - - + +
Depolarized
Polarized = not stimulated + + + + + + + + - - - - - - - - - - - - - - - - + + + + + + + +
Repolarization = restores resting potential

22. Human Reflexes and Reaction Time
The reflex arc
consists of: receptor, sensory neuron, interneuron, motor neuron, effector
a typical reflex arc is the response to pain
it involves only 3 neurons
by-passes the brain

23. The Nervous System
Structure and function of the CNS
the CNS is made of the brain and spinal cord
both are protected by bone (skull and spinal column)
both are protected by 3 tough membranes called the meninges
cerebrospinal fluid (CSF) fills the space between the inner and middle membrane and cushions both the brain and spinal cord

24. concussions occur when the brain is severely shaken, causing contact with the skull
4 spaces in the brain contain the CSF and are called ventricles
ventricles connect with the spaces between the meninges and with the central canal of the spinal cord

25. is the major user of glucose in the body
Anatomy of the Brain
is the major user of glucose in the body
major parts are the cerebrum, cerebellum, medulla oblongata
other parts are the thalamus, hypothalamus, and pons
the forebrain =the cerebrum, thalamus, and hypothalamus
the midbrain = a small area at the top of the medulla oblongata
the hindbrain = the name for the brainstem and the cerebellum
So we have a model brain for this?

26. the brainstem = a name given to the pons, medulla oblongata, and the midbrain
Cerebrum
largest part of the human brain
divided in 2 hemispheres (right/left)
a deep groove or fissure divides the 2 hemispheres
a bridge-like connection of nerve fibres between the 2 hemispheres that connects to the rest of the NS is called the corpus callosum

27. the two hemispheres do not function equally – one side may be more mathematical, the other may be artistic and musical
the left cerebral hemisphere controls the right side of the body, the right hemisphere controls the left side of the body
Functions of the Cerebrum
controls higher processes and senses (speech, reasoning, memory, smell, touch, taste, hearing)

29. Cerebellum
below the rear part of the cerebrum (back of brain)
Also has 2 hemispheres, white and grey matter
Functions of the Cerebellum
coordinates motor movement
staggering and loss of coordination results from impairment of cerebral function (drinking alcohol)

30. Medulla Oblongata
lowest part of the brain
connected to the spinal cord
Functions of the Medulla Oblongata
controls involuntary movement (heartbeat, breathing, blood pressure, yawning, etc)

31. The Spinal Cord
extends from the opening at the base of the skull, through the vertebral canal, to the lower back
conducts messages between the brain and peripheral nerves (sensory and motor)
controls reflex actions that do not require supervision by higher centers in the brain (the reflex arc)

32. Somatic and Autonomic Nervous Systems
Somatic nervous system
contains both sensory and motor neurons that connect the central nervous system to skeletal muscles, the skin, and the sense organs
is responsible for body movements over which the individual has conscious awareness or voluntary control

33. Autonomic nervous system
made up of motor fibres from the brain and spinal cord that serve the internal organs of the body
usually has no voluntary control
controls functions like rate of heartbeat, blood flow through arteries, breathing movements, movements of the digestive system, and secretions of certain glands
is made up of 2 systems:
Parasympathetic
Sympathetic
these work in opposite ways to counteract each other

34. The parasympathetic system is responsible for ‘rest and digest’ activities, and the sympathetic is responsible for ‘fight or flight’ responses
parasympathetic functions to return to normal operations of the body that were shut down or slowed down by the sympathetic system in an emergency or stressful situation