Week 2 - topic 1 Flashcards
Central nervous system
contains the brain and spinal cord
- motor nerves allow actions to be completed, triggered by the central nervous system
Peripheral nervous system
contains the nerves and most sensory organs
- sensory nerves relay sensory information towards the central nervous system
Nerves
- bundles of individual neurons contained within a protective membrane.
- They act a little bit like an electrical cable sending messages to and from the CNS to the rest of the body
- sensory neurons, motor neurons and internneurons
Parts of a neuron
The neurons of the nervous system are the parts that do the talking (information transmitting).
Neurons normally contain the following elements:
- Soma (Cell Body)
- Dendrites
- Axon
- Terminal Buttons
Soma
- cell body
- Contains the nucleus of the cell and the machinery involved in the life process of the cell.
- Soma shape varies in different neuron types.
Membrane
- Made of Double layer of lipid (fatlike) molecules
- Protein molecules embedded in membrane
- Substance detectors and Security Guards
- Transporting substances in and out of the cell
Cytoplasm
- Jelly-like substance that fills the space surrounded by the membrane including the soma
- Contains organelles
Nucleus
An organelle
- Contains the chromosomes
- Chromosomes consist of DNA
- Genes contain recipes for individual proteins
- Proteins important for structure and function
- > Serve as Enzymes
Mitochondria
An organelle
- Extract energy from nutrients
- Produce a chemical called Adenosine Triphosphate (ATP)
Dendrites
Dendrites help individual neurons talk with one another
Neural messages
Neural messages are transmitted from neuron to neuron across the synapse (synaptic cleft).
*look up image
Message = action potential
Axon
Long tube that carries information from the soma of a neuron to it’s terminal buttons
Axoplasmic transport
- Items are moved around the cell via axoplasmic transport
- There are two types of axoplasmic transport:
- > Anterograde transport: movement from cell body to terminal buttons
- > Retrograde transport: movement from the terminal buttons to the cell body
Internal structure of neuron
*look up image
Microtubules
- bundles of protein filaments arranged in a hollow core
- train tracks to propel substances down axon
- to track and transport proteins for axoplasmic transport