Chapter 1 Flashcards
CNS
PNS
CNS : a central division consisting of the brain and the spinal cord
PNS : a peripheral division consisting of the network of nerves that course through the body
What do PNS do? What is their role in regards to the CNS?
PNS conduct electrical signals to and from the CNS : efferent motor (CNS to muscle tissue) and afferent motor (muscle tissue to CNS)
What are the Primary Cortical Areas.
Name the 4 PCA.
Areas receiving inputs that are relayed to cortex through the thalamus.
- Motor
- Somatic sensory
- Auditory
- Visual
What is the role of glia?
Insulate, support and nourish neurons
Role of neurons?
- Sense environmental changes
- communicate changes to other neurons
- Process information
- command the body’s responses to sensations
What is the Nissl Stain?
What role?
Stains nucleic acids
This facilitates the study of cell structure in the CNS.
Stains all cell somas.
What does the Golgi stain show/reveal?
It shows 2 parts of the neuron :
- cell body=soma=perikaryon
- neurites :axons + dendrites
Reticular theory
Neurites of different cells fused into a continuous reticulum or “net”.
Neuron doctrine
The neurites of different neurons are not continuous with each other and communicate by contacts not continuity.
Dendrites
- short, stubby often spiny
- highly branches tree
- very there’s as it goes further from soma
Axons
- long, thinner and smoother
- fewer branches
- d’imagée more uniform
Difference between dendrite and axon
Axons are the way a neuron sends an outgoing signal
Dendrites are where a neuron receives a signal.
The soma structure is what?
- cytosol : watery fluid inside the cell
- organelles : membrane-enclosed structures within the soma
- cytoplasm : contents within a cell membrane (organelles/cytosol but not nucleus)
What is (in) the nucleus?
Not a great flash card
-chromosomes (contain the DNA)
Transcription def
Assembling mRNA by stringing together nucleic acids
Translation
Assembling of protein by stinging together amino acids
Étapes de la transcription/translation
DNA —transcription—> mRNA—translation—>protein
Rough Endoplasmic Reticulum definition
Membrane with attached ribosomes, the site of protein synthesis.
What are the two types of ribosomes?
Free ribosomes : produce proteins that re released into the cytosol and used within the cell.
Bound ribosomes : located on rER they produce proteins that are inserted into the plasma membrane.
What is the smooth ER?
Endoplasmic reticulum without ribosomes : floss proteins giving them a 3D structure, regulates internal
Ca++ concentration.
Golgi apparatus role?
Packages molecules and sends them to appropriate destination in the cell.
Neuronal membrane
Polar heads (hydrophilic) and non polar tails (hydrophobic)
What is the cytoskeleton?
- internal scaffolding of the neuron
- gives the neuron its shape
What are the 3 “bones” of the cytoskeleton?
- microtubules
- neurofilaments
- microfilaments
What is the composition of the axon?
- Axon hillock
- Axon proper
- Axon terminal
- Axon collaterals
Axoplasmic transport definition
Flow of materials from the soma to the axon terminal.
What are the 2 types of axoplasmic transport?
Anterograde : uses kinesin and proteins are shipped from the soma to the axon terminal
Retrograde : uses dynein and signals to soma metabolic needs of axon terminal
What is the most numerous glia in the brain?
Astrocytes
What are the two types of myelinating glia?
Oligodendrocytes (in CNS)
Schwann (in PNS)
What are two non neuronal cells (not glia)?
Microglia : phagocytes that remove dead or dying neurons and glia
Ependymal cells : line the brain’s ventricular system.
