Presentation on theme: "Main Function: Responds to internal and external stimuli by controlling and coordinating functions throughout the body Our nervous system allows."— Presentation transcript:
Main Function: Responds to internal and external stimuli by controlling and coordinating functions throughout the body Our nervous system allows us to feel pain and react to it!
Consists of: brain, spinal cord, nerves and sense organs Sense Organs: Eyes, Skin, Ears, Nose & Tongue
Central Nervous System (CNS) brain & spinal cord Main control center of body Peripheral Nervous System (PNS) nerves extending throughout body Gathers & delivers info to and from the CNS
Peripheral Nervous System (PNS) All of the Organs the PNS controls!!!
Neurons carry messages called impulses back and forth between the peripheral nervous system and the central nervous system.
dendrites cell body axon synapse (space) signal direction ONE WAY nucleus terminal branches signal direction ONE WAY
axon synapse (space)
signal direction myelin coating Axon is coated with insulation made of myelin cells (Lipids) With myelin…signal hops from node to node at 330mph! (vs. only 11mph) Multiple Sclerosis immune system attacks myelin coating loss of signal
synapse Because neurons never touch, chemical signalers called neurotransmitters must travel through the space called synapse between two neurons.
Neurotransmitters Synapse (gap) The message is transferred when RECEPTORS receive neurotransmitters.
Receptors: Protein Shape Specific! Drugs/Poisons Stimulants - Speed up production and release of neurotransmitters (Caffeine) Depressants – block formation of neurotransmitters. (Pain Killers)
Which cell (X or Y) shows the receptor molecules? What would a drug that interferes with communication between these two cells look like?
Sensory Neuron Interneuron Motor Neuron Sensory Neuron Interneuron Motor Neuron Muscle Contracts Synapse
A reflex is an involuntary response that is processed in the spinal cord not the brain. Reflexes protect the body before the brain knows what is going on. *faster because they don’t have to travel to brain! Reflex Arc
- Receives 20% of blood pumped by heart - Is the major user of glucose in the body Consists of 3 Parts: 1.Cerebrum 2.Cerebellum 3.Medulla (Brain Stem) What does the brain use glucose for?
Higher Brain: Cerebrum 2 hemispheres: –left controls the right side of body –right controls the left side of body
Cerebrum Functions frontal temporal Regions specialized for different functions 4 Lobes 1. frontal speech, control of emotions 2. temporal smell, hearing 3. occipital vision 4. parietal speech, taste reading occipital parietal
Cerebellum Found in back part of head under the cerebrum coordination of smooth, steady and efficient MOVEMENT BALANCE, equilibrium and posture If damaged can result in jerky movement, loss of coordination and balance
Bone: Skull, Vertebrae Cartilage disks found between vertebrate absorb shock Meninges (protective membrane) cover the brain and spinal cord Cerebral Spinal Fluid surrounds Brain and Spinal Cord. Acts like a watery cushion!
When homeostasis is distrupted!
Cerebral Palsy: A group of birth disorders characterized by disturbances of motor functions.
Polio: A viral disease of the CNS that can cause paralysis. Prevented by immunization!
Meningitis – an inflammation, caused by bacteria, of the membranes that surround the brain and spinal cord. Can be fatal. Symptoms: severe headache, stiff neck
Concussion: The Brain is a soft organ protected by your hard skull surrounded by spinal fluid (cushion that keeps your brain from banging into your skull) Hard hit/fall=Brain crashes into your skull=Damaged Brain