The Nervous System
1. Two main divisions a. Central Nervous System (CNS) – consists of brain and spinal cord b. Peripheral Nervous System (PNS) – includes nerves extending from brain and spinal cord c. The CNS receives messages from the PNS, interprets them, and then sends out a response.
Neurons 2. Neurons - nerve cells that transmit messages to and from the spinal cord and brain a. Sensory Neurons – carry messages FROM body TO CNS ex. Playing games in computer lab. When light switches to green, a sensory neuron transmits a message from your eye to your brain
Neurons b. Motor Neurons – carry message TO body FROM CNS ex. Your brain sends a signal through a motor neuron to tell your finger to click the mouse. c. Interneurons – connect neurons
What does a real neuron look like?
3. Structure and Functions of Neurons 1. Dendrites – receive information and transmit impulses toward cell body 2. Cell Body – large area which contains cell nucleus or power plant 3. Nucleus – command center of the neuron
4. Axon – transmit impulses away from cell body and toward axon terminal 5. Axon Terminals – branched structures at the ends of neurons. 6. Myelin Sheath – insulating coat which covers the axon. This helps messages relay faster.
Neuron
Nerves of the Body
Motor Unit Motor Unit – A neuron and all the muscles it gives power to.
The Central Nervous System 1. The brain a. Helps you think, remember, reason, feel emotion, and coordinate muscle movement b. Divided into three main parts: cerebrum, cerebellum, brain stem
The Brain
The Central Nervous System 2. The Cerebrum a. largest, most complex part of brain b. right and left sides communicate with each other to coordinate movement. Right controls left side and vice versa. c. left hemisphere is for more concrete thinking d. right hemisphere is for abstract thinking
Are you left or right brained?!
The Central Nervous System 3. Four lobes (parts) of the cerebrum a. Frontal Lobe –use of language b. Parietal Lobe – sensory information, including feelings of heat, cold, pain, touch c. Occipital Lobe – Controls sense of sight d. Temporal – sense of hearing and smell
Frontal Lobe Exercise: Unscramble the following words: LLBA DLOFER EPONH PHELNATE ICINMDEE
Parietal Lobe Exercise: 1. Blow on your hand 2. Now, puff your breath on your hand
Temporal Lobe Exercise: Whisper down the lane! Shhhh!
Whisper… She sells seashells by the sea shore. Eleven owls licked eleven little liquorice lollipops." If two witches were watching two watches, which witch would watch which watch?“ If you want to buy, buy, if you don't want to buy, bye bye!"
Occipital Lobe Exercise:
Lobes of the Brain
The Central Nervous System 4. The Cerebellum a. second largest part of brain b. maintains body’s posture and balance c. coordinates complex muscle movements like serving a volleyball or playing violin
Balancing Competition!!!
The Central Nervous System 5. The Brain Stem a. 3 inch long stalk of nerve cells that connect the spinal cord to the rest of the brain
The Central Nervous System b. five parts 1. Medulla Oblongata – regulates heartbeat, breathing rate 2. Pons – controls muscles of eyes and face. 3. Midbrain – controls pupil size 4. Thalamus – relays incoming information from the eyes, ears, and pressure receptors in skin 5. Hypothalamus – regulates body temp, appetite, sleep
Brain Stem
Activity 1 Find pulse/HR 25 Jumping Jacks! Jog in place!
Brain Stem 1. Medulla Oblongata – regulates heartbeat, breathing rate
Activity 2 Watch the video!
Activity 2
Brain Stem 2. Pons – controls muscles of eyes and face.
Activity 3 Find a partner… Look into their eyes!!! oooooooo
3. Midbrain – controls pupil size
Activity 4 What does a switch board do?
4. Thalamus – relays incoming information from the eyes, ears, and pressure receptors in skin
Activity 5 Imagine you are stranded on a cold (20 degree) deserted island with no supplies, food, or shelter. You haven’t slept in two days, nor have you ate in two days. How would you be feeling???
5. Hypothalamus – regulates body temp, appetite, sleep
The Peripheral System 1. Broken into two parts a. Autonomic Nervous System – controls involuntary functions such as digestion and heart rate - you cannot control this; it is automatic! (autonomic) b. Somatic Nervous System – voluntary responses that are under your control - feeling and itch on your skin and scratching it, or giving someone a high five
The Peripheral System 2. Autonomic Nervous System a. Broken down into two smaller networks b. First part is the Sympathetic nervous system Watch these clips… qQbIiOtYM mUDknB2YWM
Sympathetic Nervous System - kicks in when you are startled. Your heart rate increases. Also, blood vessels dilate to allow for greater blood flow. - “Fight or flight response” - Rush of adrenaline - Example… You pick! Write one down…
So, how exactly does all this work?
The Peripheral System c. The second part: Parasympathetic nervous system – opposite of sympathetic nervous system - slows heartbeat, relaxes blood vessels, lowers blood pressure
Problems of the Nervous System 1. Headaches – caused by muscle tension, eyestrain, sinus infection, dehydration, or food allergies 2. Head injuries a. concussion – a temporary loss of consciousness
Problems of the Nervous System 3. Spinal Injuries a. swelling of spinal cord tissue can result in temporary loss of nerve function b. if spinal cord is severed, you may become paralyzed.
Problems of the Nervous System 4. Meningitis – inflammation of the spinal and cranial meninges caused by a virus or bacteria a. symptoms include fever, headache, light and sound sensitivity, and neck stiffness. b. can result in death
How to care for/prevent these problems: 1. Eat a well-balanced diet, exercise regularly, get lots of sleep! 2. Wear protective devices – helmet, seat belt 3. Stay away from drugs and alcohol!!!