Unit 4

Nervous System-it starts with an individual nerve cell called neuron

how a neuron fire:

1-restingpotential: slightly negative charge ;2-reach the threshold when enough neuron-transmitters reach dendrites;3-go into action potential (firing)

The All or None Response- the idea that either the neuron fires or it does not not-no part way firing.

Types or Neurotransmitter:

Acetlycholing (ACH)- deals with motor movement and memory. Lack  of ACH has been linked to Alzheimer's disease

Dopamine- deals with motor movements and alertness. Lack of dopamine has been linked to  Parkinson's disease. Too much has been linked to schizophrenia.

Serotonin- involved in mood control. Lack of serotonin has been link to clinical depression

Endorphin-involved in pain control. Many of our most addictive drugs deal with endorphin.

Norepinephrine-helps control alertness and arousal. An under supply can lead to depression. AN over supply can lead to manic symptoms.

GABA (gamma-aminobutytic acid)-major inhibitory neurotransmitters. An under supply can lead to tremor.

Types Neurons:

• Sensory neurons-take information from the senses to the brain
• Inter neurons- take messages from sensory neurons to other parts of the brain or to motor neurons.
• Motor neurons-take information from the brain to the rest of the body