nervous system human physiology. the body’s control center the brain is the control center of the...
TRANSCRIPT
THE BODY’S CONTROL CENTER
The brain is the control center of the human body.
It is made up of billions of nerve cells, or neurons.• Sends messages around the body• Receives messages from the body• Stores information
THE BODY’S CONTROL CENTER
Message go from your brain down to your spinal
cord.• Big rope of nerve cells• Runs along the inside of your back bone• Connects to neurons all over your body
THE BODY’S CONTROL CENTER
Hormones are substances made by organs called
glands• Hormones control body functions• Some circulate in the blood and cause changes• Estrogen and testosterone are examples of
hormomes
THE NERVOUS SYSTEM
Body parts: brain, spinal cord, sense organs and
neurons are all parts of the nervous system
Function of the nervous system: Main
controlling and communicating system of body
THE FIVE SENSES
All part of the nervous system
Sight – eyes are organs of sight
Hearing – ears are organs of hearing
Taste – tongue is the organ of taste
Smell – nose is the organ of smell
Touch – skin is the organ of touch
SIGHT
Sight – eyes are organs of sight• Light bounces off objects and enter your eye• Nerves in back of eye sends messages to brain
HEARING
Hearing – ears are organs of hearing• Sounds are made by vibrations• Tiny bones in your ears pick up vibrations• Nerves pick up movement and send message to
brain
TASTE
Taste – tongue is the organ of taste• Four types of flavors: sour, sweet, salty and bitter• Different areas of tongues taste different flavors• Taste buds pick up tastes and send them to brain
SMELL
Smell – nose is the organ of smell• Molecules leave object and trigger nerve cells in
nose• Sends messages to brain
TOUCH
Touch – skin is the organ of touch• Some areas are more sensitive to touch than others• Fingertips very sensitive to heat, cold, touch and
pain• Skin is the largest organ of body• Also part of immune system – keeps germs out of
body