Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Characteristics • Made up of two parts: – Central Nervous System (CNS) – Peripheral Nervous System (PNS) • Made up of: – Brain – Spinal Cord – Neurons – 5 Senses Job of the Nervous System • Allows you to react to a stimulus – Stimulus: change in the environment – Example: hot stove, tripping on a rock… • Your reaction is Automatic! – Example: if a bug flies in your eye, you blink. You don’t have to think about it. Neurons Neuron • Dendrites - receive impulses from other neurons and carry them to the cell body • Axon - an elongated extension of the cell body that carries impulses away from the cell body • cell body - containing the nucleus Central Nervous System • Made up of 2 organs: – Brain – Spinal Cord • Controls everything you do The human brain • Controls everything in the body • Made up of more than 10 billion nerves! • Three Parts – Cerebrum – Cerebellum – Brain Stem or Medulla • Protected by the skull The Brain Cerebrum • Contains 75% of your neurons • Composed of two equal hemispheres • Frontal lobe reasoning, speech, movement, and emotions • Parietal lobe touch, pressure, temperature, and pain • Temporal lobe hearing and memory • Occipital lobe vision The Brain Cerebellum • Located at the lower back of the head. • Controls muscle coordination and balance. Brain stem or Medulla • Connects the cerebrum with the spinal cord • The 3 main sections of the Brain Stem • Midbrain - controls reflexes and changes pupil size • Medulla oblongata - controls heart rate, breathing rate, and flow of blood through the blood vessels. • Pons - relays signals between the cerebrum and the cerebellum. Spinal Cord • Protected by the vertebrae • Sends messages to the brain • Connects the brain to the rest of the nervous system (PNS) Peripheral Nervous System (PNS) • Made up of: – Nerves that connect the Central Nervous System (CNS) to the rest of the body – Sense organs PNS Con’t • Ganglion - a mass of nerve cells outside the central nervous system • Receptors - nerve cells that receive information from internal and external stimuli. PNS Con’t • Conductors - nerve cells that transmit information from receptors to the central nervous system. • Effectors - receive information from the central nervous system and transmit to the body. These cells activate muscles. Job of the PNS • Controls the body’s activities that you don’t think about – Breathing – Heartbeat – Small intestine controls The Five Senses • Touch • Taste • Hearing • Smelling • Seeing Seeing • Main organ is the eye • Made up of: – Iris (colored part) – Pupil (black hole) • The eye gathers pictures and sends them to the brain through the optic nerve Eyes Hearing • Main organ is the ear • Made up of: – 9 parts – 3 smallest bones in the body • The ear takes in sound waves and transmits them to the brain through the auditory nerve deep within the ear Touching • Main organ is the skin • The skin allows us to feel things (temperature, pressure, pain, etc.) and transmit that information back to the brain through the nerves in the skin. Smelling • Main organ is the nose • Made up of: – Nose – Olfactory cells • Transmits smells to the brain through the olfactory bulb Tasting • Main organ is your tongue • Made up of: – Taste buds (sweet, sour, bitter, salty) – Hypoglossal nerve • Taste information from the buds on your tongue is transmitted to your brain through the hypoglossal nerve in your tongue. ** There are NOT specific areas on your tongue that have specific tastes!!!