Presentation on theme: "The Nervous System JORDIE SMELLS LIKE FEET IN THE SUMMER ON A HOT DAY BECAUSE HE LIKES TO EAT “HOTDOGS” ALL THE TIME."— Presentation transcript:
The Nervous System JORDIE SMELLS LIKE FEET IN THE SUMMER ON A HOT DAY BECAUSE HE LIKES TO EAT “HOTDOGS” ALL THE TIME.
Organization of the body The levels of organizations in a multicellular organism goes as follows: Cells, tissues, organs and organ systems. There are 11 organ systems that help maintain homeostasis.
Homeostasis It means to keep things in balance. Homeostasis keeps internal conditions relatively constant despite change to external environments.
Feedback Inhibition The process in which the stimulus produces a response that opposes the original stimulus. Systems controlled by feedback inhibition are generally fully automated and very stable. Ex: Like a thermostat.
The Actual Nervous System The nervous system controls and coordinates function throughout the body and responds to internal and external stimuli. The messages carried by the nervous system are electrical signals called impulses. These cells are called neurons. These cells are called neurons.
CONTINUED The largest part of a typical neuron is the cell body, it contains the nucleus and much of the cytoplasm. The dendrites which are attached to the cell body, carry impulses from the environment or other neurons to the cell body. It is then carried away from the cell body through a long fiber called the AXON. It is then carried away from the cell body through a long fiber called the AXON.
CONTINUED AGAIN The axon is surrounded by the myelin sheath. The myelin sheath basically increases the speed at which a impulse can travel.
The Synapse The synapse is the location at which a neuron can transfer an impulse to another cell. NEUROTRANSMITTERS are chemicals used by a neuron to transmit an impulse across a synapse to another cell. NEUROTRANSMITTERS are chemicals used by a neuron to transmit an impulse across a synapse to another cell.
Central Nervous System It relays messages, processes information & analyzes information. It consists of the brain and spinal cord. It consists of the brain and spinal cord. Cerebrospinal fluid bathes the brain and spinal cord and acts as a shock absorber to protect the central nervous system! It allows for exchange of nutrients and waste products between blood and nervous tissue. It allows for exchange of nutrients and waste products between blood and nervous tissue.
The Brain Pinky and the Brain are awesome. Pinky and the Brain are awesome. The cerebrum is the largest part of the brain, its responsible for intelligence, learning, and judgment.
Still part of the Brain The cerebellum is the second largest part of the brain. It coordinates and balances the actions of the muscles so the body can move efficiently.
More Brain Parts The Brain Stem connects the brain and spinal cord. It regulates the flow of information between the brain and the rest of your body. Blood pressure, heart rate, breathing & swallowing are controlled by the BRAIN STEM! Blood pressure, heart rate, breathing & swallowing are controlled by the BRAIN STEM!
The other part of the central nervous system The spinal cord is the main communication link between the brain and the rest of the body. A reflex is a quick automatic response to a stimulus such as SNEEZING and BLINKING. A reflex is a quick automatic response to a stimulus such as SNEEZING and BLINKING. I know you all blink.
The Peripheral Nervous System It is divided up into the sensory division and motor division. Sensory division takes care of the senses, such as smell, seeing, hearing, feeling and taste. Motor division takes care of movements, such as thrusting and walking.
The Somatic and Autonomic System The somatic system is anything you have conscious control over. Such as, moving you finger around, and wiggling your tongue unbelievably fast. The autonomic system is anything you DON’T have conscious control over. Such as breathing heavily and blinking.
The Eye It sees stuff. Light enters the eye through the cornea, the cornea helps focus the light which then passes through the chamber filled with fluid called the aqueous humor. At the back of this chamber is the iris, the color part of the eye with an opening called the pupil.
More Eye Stuff There are two types of photo receptors. Rods. Cones. Rods are extremely sensitive to light but they do not distinguish different colors. Cones are less sensitive then rods but they do respond to light of different colors producing color vision.
Drugs Stimulates increase heart rate, blood pressure, in addition stimulates increase the release of neurotransmitters at some synapse in the brain. Depressants slow down heart rate, breathing rate, lower blood pressure, relax muscles and relieve tension.
More Drugs COCAINE causes sudden release in the brain of neurotransmitters called dopamine. Opiates mimic natural chemicals in the brain known as endorphins, which normally help to overcome sensations of pain.