Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
41 Cards in this Set
- Front
- Back
|
an active process by which substances are propelled along microtubules that run the length of the axon
|
axoplasmic transport
|
|
|
In a direction along an axon AWAY from the cell body toward the terminal button
|
anterograde (FAST)
|
|
|
in a direction away from the terminal button toward the cell body.
|
Retrograde (SLOW)
|
|
|
Support cells. Cells that provide nutrients, housekeeping and structure for neurons
|
Glial cells
|
|
|
3 types of glial cells
|
Astrocytes
oligodendracites microglia |
|
|
Astrocytes function to
|
provide physical support and housekeeping duties (regulate chemical compositions around neurons)
|
|
|
Astrocytes can be found around capillaries because
|
they fxn to recieve nutrients brought by the capillaries. Astrocytes then break down the glucose to lactate for the neurons use.
|
|
|
Astrocytes also mantain a small amount of...
|
glycogen for later breakdown to glucose if necessary.
|
|
|
The protein that "walks" along microtubules to relay messages is
|
Kinesin
|
|
|
Oligodendrocytes serve two main functions
|
1.) Provide support for the axons
2.) PRODUCE MYELIN SHEATH |
|
|
Myelin sheath is 80% _______ and 20 % ________.
|
Lipid; protein; the sheath is not continous along the axon, it is in patches (1 mm) and spaces of bare axon are called Nodes of Ranvier.
|
|
|
Microglia serve two functions
|
1.) they like astrocytes participate in phagocytosis
2.) More importantly, they are responsible for immune response in the brain to protect from invading microbes (particularly inflammatory reaction). |
|
|
Schwann cells
|
counterpart of oligodendrocytes in the peripheral nervous system. Like their counterparts they are segmented along the axons. they differ by several ways:
1.) Schwann cells aid in degradation and digestion of dying neurons, then they align and reform them. 2.) Schwann cells completely surron the axons of the neurons. in fact, they wrap themselves several times. Realize that differences in the regeneration of neurons is not caused by the axon but by differences in the supporting cells (oligodendrocytes vs Schwann cells) |
|
|
Membrane potential has what ions inside and what ions outside?
|
Na and Cl are outside and K+ ions inside. Recall Na-K pump, pumps 2 K+ in per 3 Na+ out of the cell.
|
|
|
There are two forces that keep a membrane potential they are?
|
Electrostatic forces and concentration forces (diffusion)
|
|
|
How is membrane potential kept according to each of the 3 main ions? Cl-, K+ and Na+?
|
Cl- remember is outside. diffusion would push it into the cell but the inside is already negative (cancels effect).
K+: recall is inside the cell so diffusion would push it out, however the negative inside the cell keeps it inside. Na+: is outside the cell so diffusion pushes it in and the potential inside is negative so it would invite a cation. so why does it remain outside? NA-K pump. |
|
|
the ion channels responsible for the action potential require a specific potential before opening and are therefore called
|
voltage dependent ion channels
|
|
|
Neurotransmitters vs Neuromodulators
|
Neurotransmitters send messages across to a post synaptic cell and are released in low concentrations. Neuromodulators are released in higher concentration and diffuse across larger distances.
|
|
|
Three types of neurons
|
Multipolar- 1 axon many dendrites
Bipolar- 1 axon and one dendrite unipolar- a neuron where the axon divides. |
|
|
Three types of synapses
|
axodendritic
axosomatic axoaxonic |
|
|
Synaptic vesicles
|
hollow structures found in the terminal buttons that contain neurotransmitters to be released into the synaptic space.
|
|
|
An approaching action potential to the terminal buds causes an opening in what ion channel?
|
Calcium. Calcium ions rush into the cell and play an important role in the release of neurotransmitters. without calcium, the neurotransmitters are not released.
|
|
|
What happens to the synaptic vesicles once neurotransmitter has been released?
|
they remain fused to the membrane and are recycled along with the rest of the membrane by a process called pinocytosis.
|
|
|
Neurotransmitters diffuse across the synapse to the post synaptic cell where they bind to...
|
postsynaptic receptors
|
|
|
once on postsynaptic receptors what are the two methods they enter the next neuron?
|
1.) Ionotropic receptors- when a neurotransmitter binds to these receptors an ion channel opens up allowing it through.
2.) Metabotropic- when a neurotransmitter binds to the binding site a cascade of signal is passed along (G-protein to secondary messenger)the neuron and an ion channel somewhere along the membrane of the post synaptic cell. |
|
|
Binding of neurotransmitter to the next cell can result in depolarizing or hyperpolarizing of the cell. This is dependent upon...
|
not the neurotransmitter but the ion channel to which it binds on the opposite cell... If it binds to Na channel for example it will be depolarizing (excitatory).
|
|
|
the effects of binding to Cl channel? Ca2+ channel?
|
Cl: it depends it will either do nothing because it is balanced by concentration forces and electric forces OR it will return the potential to membrane potential.
Ca: binding to calcium is even stronger than opening Na channels for action potentials because it is a +2 charge per ion instead of +1. |
|
|
Termination of Postsynaptic potentials
|
1.) Reuptake- the reuptake of neurotransmitters released back into the cytoplasm of the cell it originally came from.
2.) enzymatic deactivation- for acetylcholine |
|
|
within the forebrain 2 components:
|
Telencephalon and diencephalon
|
|
|
The telencephelon includes most of the ______________ hemisphere and is covered by what structure? What major brain parts are located in this region?
|
cerebral hemisphere; cerebral cortex.
Limbic system and the basal ganglia. (both of which are subcorticol- deep within these regions). |
|
|
The structure of the cerebral cortex is highly convoluted it has what kinds of grooves? purpose?
|
Large grooves- Fissures
Small grooves- sulci bulges between adjcent fissures and sulci= gyri To enlarge the surface area. |
|
|
Because cell bodies predominate in the cerebral cortex it is called.
|
Gray matter
|
|
|
Beneath the cerebral cortex there are plenty of myelinated axons giving it the name
|
White matter.
|
|
|
The cerebral cortex recieves SENSORY information from 4 sites...
|
1.) Primary visual cortex located at "caudal" part of the brain right below the Calcarine fissure (spur-like)
2.) Primary auditory cortex- along the lateral fissure (the fissure which seperates temporal from (parietal and frontal) lobes. 3. Primary motor cortex- the most posterior structure of the frontal lobe. contains neurons that control movement. spands all the way across the brain. 4.) primary sematosensory cortex: the most anterior of the parietal lobe. Front to back it is right after the primary motor. |
|
|
the structure that divides the frontal and parietal AND serves as a division between primary motor and primary somatosensory is called...
|
central sulcus
|
|
|
just rostral to the primary motor cortex is the ____________ and anything rostral to that structure is known as
|
motor association cortex; prefrontal cortex
|
|
|
Brain lateralization
Left: Right: |
Analyze and serial events
Synthesis, map reading, |
|
|
Limbic system is located... major functions... structures.
|
Just beneath the neocortex. motivation and emotion. amygdala and hippocampus.
|
|
|
what is connected to the hippocampus and the structure that connects them
|
mammilary body and the fornix
|
|
|
limbic system functions for
|
learning and memory
|
|
|
basal ganglia responsible for what...
|
movement
|
