Nervous System Term | Answer |
Nervous System | The control system of the body |
Stimulus | Any internal or external change that brings about a response. |
Types of External Stimuli | Noise, light, the smell of food, and the temperature of the air. |
Types of Internal stimuli | Chemical substances such as hormones. |
What are the two anatomical divisions of the nervous system? | 1. Central Nervous System (CNS) 2. Peripheral Nervous System (PNS). |
What does the CNS consist of? | Brain, Spinal Cord |
What does the PNS consist of? | All of the nerves outside of the CNS, cranial nerves and spinal nerves. |
What does the PNS connect? | The brain and spinal cord to other body parts. |
Name the three parts of the brain. | 1. Brain stem 2. Cerebellum 3. Cerebrum |
Cerebrum | The largest part of the brain where thinking takes place, input fromsenses are interpreted and memory is stored. |
Cerebellum | Controls voluntary muscle movements, maintains muscle tone, and helps maintain balance. |
Brain Stem | Located at base of brain, controls involuntary actions such as heart beat, breathing and blood pressure. |
Spinal Cord | Carries signals from all parts of the body to the brain and from the brain to all parts of the body. |
Vertebral column | Protects the spinal cord |
A severe blow to the head can result in.. | Temporary or permanent loss of mental and physical abilities |
Injury to the spine can result in.. | Paralysis..a loss of muscle movement. |
What are the basic functional units of the nervous system? | Nerve cells or neurons. |
How many neurons is the brain made up of? | 100 billion neurons. |
What is a nerve cell made up of? | A cell body and branches called dendrites and axons. |
What is a synapse? | When there is communication between the dendrite of one nerve cell and the axon of another nerve cell. |
What happens during a synapse? | An impulse reaches the end of an axon and the axon releases a chemical, this chemical flows across the synapse and stimulates the impulse in the dendrite of the next neuron. |
In what direction does an impulse move? | Neurons are adapted so that they move in only one direction like a relay race with the baton represented the chemical at the synapse. |
What is a reflex? | An involuntary automatic response to a stimulus. |
Can you control reflexes? Why? | No, you cannot control reflexes because they occur before you know what has happened. |
What does a reflex or reflex arc allow the body to do? | It allows the body to respond without having to think about what action to take. |
Where are reflex responses controlled? | In you spinal cord, not your brain. |
Why does the brain act after a reflex? | The brain acts after a reflex to help you figure out what to do to make the pain stop. |