Neuron structure

Central Nervous System (CNS) - brain & spine

Peripheral Nervous System (PNS) - nerves in body:

• Somatic = interacts w/ env to receive sensory info and control muscles
• Autonomic = regulates internal env e.g. cardiac muscles
• Parasympathetic = conserves energy
• Sympathetic = stimulates body e.g. fight or flight

Sensory neurones, motor neurones and interneurones (CNS)

Reception, conduction and transmission of electrochemical signals (100-1000 billion)

Soma = metabolic centre of cell - contains nucelus and intracellular fluid

Cell Membrane

Nucleus = contains chromosomes, produces proteins & some produce MRNA

Cytoplasm = keeps everything in place and protects cell

Mitochondria = extracts nutrients to adenosine triphosphate (ATP)

Golgi Apparatus = modifies and sorts proteins

Dendrites = form synapses with other neurones as a post-synaptic cell

Axon = carries message (action potential) to terminal buttons. Secretes neurotransmitters when message reaches it

Unipolar = one axon into two branches

Bipolar = one axon and one dendritic tree at both ends of soma

Multipolar = one axon, several dendritic branches and can receive 150,000 contacts

Glia Cells = most supporting of CNS. Buffer neurones that control nutrients and insulate etc

• Astrocytes = physical support, clean debris and control fluid's chem composition
• Olgiodendrocyte = insulate forming myelin sheaths
• Schwann = only insulate one cell by wrapping around it and guide axonal regeneration - forms cylinders