Nervous system
Teaching Points 1. The functions of the nervous system is to receive the information happening in both inside and out of the body, respond to the information and lastly maintain homeostasis. 2. The structure of a neuron includes the cell body with a nucleus, extensions called dendrites and an axon. 3. The central nervous system is in control of the center part of the body and consists of the brain and the spinal cord. 4. The peripheral nervous system controls nerves that connect out of the central nervous system and involves both voluntary and involuntary actions 5. The sense in our body includes vision, hearing and balance, smell and taste, and touch
Bell Work
Function Of The Nervous System
Receiving Information Makes you aware of what is happening around you Checks what is going on inside your body (ex: glucose rate in the blood)
Responding To Information Stimulus -> change or signal in the environment that can make an organism react Response -> what your body does to react to the stimulus Heart rate -> controlled by involuntary actions of the nervous system
Maintaining Homeostasis The nervous system maintains homeostasis by directing the body to respond appropriately to the information it receives Ex: You get hungry when your body needs food
The Structure Of A Neuron A neuron is a nerve cell.
Structure Of A Neuron Large body cell with a nucleus Dendrites carry impulses towards the cell body The axon carries impulses away from the cell body Bundle of nerve fiber = nerve
Kinds Of Neurons Sensory neuron -> picks up stimulus from the environment and converts it into nerve impulses Interneuron -> carries nerve impulses from one neuron to another Motor neuron -> sends impulse to muscle or gland and react in response
How A Nerve Impulse Travels Synapse -> the junction where one neuron transfers an impulse to another structure There is a gap between axon tips and dendrites
Central Nervous System Includes the brain and a spinal cord Brain -> controls most functions of the body Spinal cord -> links brain to most of the nerves in the outer body system
The Brain and Spinal Cord Has three layers of connective tissue Between the innermost layer and the middle layer, it is filled with fluids to protect the brain
The Brain Three main regions that receive and process information 1 cerebrum 2 cerebellum 3 brain stem
Cerebrum Left Half Right Half Interpret inputs from the senses, control movement, and carries out complex mental process (ex: learning/remembering) Largest part of the brain Left Half Right Half Controls right skeleton muscles Controls left skeleton muscles Mathematical skills Creativity Logical thinking Artistic ability
Cerebellum and Brain Stem Cerebellum -> coordinates actions of your muscles and helps you keep your balance Brain Stem -> involuntary actions that occur
Spinal Cord The link between your brain and the rest of the body Vertebral column -> surrounds the spinal cord to protect them
Peripheral Nervous System Network of nerves that branch out from the central nervous system Controls both voluntary and involuntary actions 43 pairs of nerves 12 pairs in the brain 31 spinal nerves
How Spinal Nerves Function Impulses travel on a spinal nerve both to and from the nervous system
How Each Function Spinal neurons -> carry both sensory and motor neurons Sensory neurons (Impulse :body -> central nervous system) Motor neurons (Impulse: central nervous system -> body)
The Somatic and Automatic Nerves of the peripheral nervous system can be divided into two groups Somatic Nervous System -> controls voluntary actions Automatic Nervous System -> controls involuntary actions
Reflex -> automatic response that occurs rapidly without conscious control Some reflex actions only interact with the spinal cord Impulses make you feel pain for protection Reflexes
The Senses Vision Hearing/Balance Smell/Taste Touch
Vision Stimulus of light converts into impulses to let you see Cornea, pupil, iris, lens, and retina are the parts of your eyes
Hearing/Balance Sounds is produced by vibrations Outer ear: gathers sound waves Middle ear: eardrum that vibrates sound Inner ear: has auditory nerves Semi-circular canals control your balance
Smell/Taste Chemicals that make you smell and taste 50 basic odors 5 main tastes – sweet, sour, salty, bitter, umami Nose and mouth work together
Touch Skin is the largest sense organ that contain touch receptor everywhere Touch, pressure, temperature change, and pain are dermis feels
Video
Activity Right now we all will do an activity in which you all will become part of the nervous system Let’s All Go Out On The Roof