Cell Biology III and Action Potential Flashcards
What does the cytoskeleton of a neuron consist of?
Microtubules, microfilaments and neurofilaments.
How is it called when free ribosomes seem to be attached on a thread?
Polyribosome
What is a polymer?
A long strand of small proteins.
How is it called when small proteins are enjoined to a long strand?
Polymerization
Are a neuron’s membranes of the soma and the axons identical?
No!
Does protein synthesis also happen in the axon?
No, just in the soma. There are very few or no free ribosomes and there is no ER in an axon.
What are astrocytes?
Glial cells
What is one of the functions an astrocytes serves?
Enclosing a synaptic cleft, thereby restricting the spreading of neurotransmitters.
How can glial cells influence synaptic activity?
By controlling the blood flow and glucose transport!
What glial cells are responsible for the formation of blood-brain-barriers?
Astrocytes
In the development of neurons the cell precursor is guided by?
Soluble and stationary signals
During the development of a new neuron, what guides the growing axon towards the postsynaptic cell?
Growth factors and stationary signals.
Describe the role of adhesion proteins during the development of neurons!
They establish the contact between an axon and what will soon be the postsynaptic neuron. After they established contact a synapse is formed.
What does synaptogenesis mean?
The formation of a synapse.
Basic function of a finished neuron in four stages:
- Integration of all synaptic input
- Due to the integration an action potential is either initiated or not at the axon hillock
- The action potential runs along the axon and …
- … triggers transmitter release at the axon terminal.
Ion channels allow efflux along …
… concentration gradient.
What is reached when there is an equal number of Na+ and Cl- in both compartments?
Electroneutrality
What does Cl- stand for?
Chloride
What does Na+ stand for?
Sodium
What is sufficient to generate an ion equilibrium across a membrane?
Open ion channels
What is needed do generate unequal ion distribution?
ATPase
What does ATPase do?
It catalyzes the decomposition of Adenosine triphosphate (ATP) into Adenosine diphosphate (ADP).
What is the energy used for that is generated by transmembrane ATPase?
To move solutes across the membrane, usually against the concentration gradient.
What is a solute?
A solute is a substance dissolved in another substance, known as solvent.
