From Brain To Neuron Flashcards
What are the functions of the ventricles?
Contain cerebrospinal fluid (CSF). Whole volume of CSF is replaced 3-4 times a day. CSF cushions the brain. Ventricles go all the way through the spinal cord with CSF bathing every cell. CSF contains high concentration of sodium and low concentration of potassium. CSF also clears the brain of unwanted products, e.g. broken down proteins.
What are the main parts of the blood supply?
Brain needs lots of energy = specialised blood supply. Has a dense network of blood vessels. Brain can regulate its blood supply.
Main elements of a neuron
They transmit and process info using electrical signals. Dendric tree receives input to the neuron, the soma integrates info from the neuron. Neuron makes a decision at the top of the axon: it makes a decision to do something it fires an action potential along the axon, and the axon terminal releases neurotransmitters onto another cell. Axon has a myelin sheath, helping the action potential to act fast.
What are the three types of glial cells and what are their function?
(a) astrocytes - contact with blood vessels. Lots of supportive roles to the neuron. Modify neuronal function.
(b) Oligodendrocytes - wrap myelin sheath around axon to insulate it and allow impulses to travel faster. Make myelin.
(c) microglia- brains immune cell - surveys brain for infection/damage and removes any damaged tissue/infection.
How do cells signal electrically?
Cells are surrounded by a lipid membrane (means water soluable things can’t pass through). Water is slightly polarised - has negative and positive parts which means charged things can bind to it.
What are equilibrium potentials?
Potentials across membrane at which there is no net flow of an ion. EP dictated by concentration and ion difference.
What is a membrane potential?
Set by electrochemical gradient and permeability of membrane to different ions. Membrane slightly permeable to sodium.
How do brain areas connect?
Performed by a neuronal circuit that takes place in several brain areas: while different brain regions carry specific functions, they need inputs and outputs to perform these computations properly - connections with different brain areas allow this to happen.
