neurons/nervous sustem

Neuron

Nerve cell in the brain

Dendrites

Branches around the cell

What do dendrites do?

Integrate messages

Cell body

Has genetic information and gives energy

Myelin Sheath

Fatty tissue around axon

What does the Myelin Sheath do?

Speed up electrical impulses

Axon

Neuron extension

What does the axon do?

Pass messages and conducts action potential

Glial Cells (glia)

Form the Myelin Sheath

What do glial cells do

Provide support, nutrition, & protection

Multiple Sclerosis

Degradation of the myelin stealth. Results in loss of muscle control.

Sensory Neurons

Sense the signal

Afferent Neurons

Approach brain with information

Motor Neurons

Carry information to muscles & glands

Efferent Neurons

Exit spinal cord

Resting potential

Imbalance of electrical charge between inside & outside of a neuron when not used

What charge is the inside

Negative (potassium ions)

What chards in the outside

Positive (sodium ions)

Ion channels

Gates in axon that allow ions in & out to change the charge

Depolarization

Inside of cell becomes more positive charged

Threshold

The specific charge that must be reached before action potential is fired

Action potential

Firing of neuron

Reuptake

Excess transmitters in synapse are reabsorbed, or broken down

Neurotransmitters

Released for axon terminal buttons and into synapse

Receptor

Area on dendrite where transmitters attach

Central Nervous System (CNS)

brain & spinal cord

Peripheral Nervous System (PNS)

Made of the somatic & autonomic system

What does the CNS do?

receives information and controls body response

What does the PNS do?

Connects the brain & spinal cord to get info

Somatic System

Control voluntary movement of skeletal muscles

Autonomic System

Control involuntary movements ex: heart beat, digestion 

2 systems of the Autonomic system

Sympathetic, Parasympathetic 

Sympathetic System

Prepares body for environmental threats

Parasympathetic System

Calms body down after threat