Neuroscience Basics Flashcards
What are the 3 roles of the nervous system?
- controls and coordinates the other organs and systems in the body - allows an organism to sense its environment and make decisions based on what the environment tells us - controls and coordinates muscle and movement
Define a neuron.
Cell that transmits electrical signal
What is a nerve?
Axons of multiple neurons bundled together.
Afferent neutrons go _____ the CNS and efferent neutrons go _____ the CNS
Aff - towards Eff - away from
In a bilaterally symmetrical organism, what 3 functional divisions is the nervous system organized into?
- afferent - integration - efferent
What are the two exceptions to cephalization?
Echinoderms and Cnidaria
As the complexity of the organism increases, nervous systems have _____ nerves.
More
What about the vertebrate nervous system is unique?
The central nervous system; brain and spinal cord encased in cartilage/bony cover.
What are the two main divisions of the vertebrate nervous system?
Central and peripheral
The ________ nervous system is the “involuntary nervous system” and is involved in homeostasis.
Autonomic
What are the three branches of the ANS?
- sympathetic - parasympathetic - enteric
Describe the function of the enteric nervous system.
Affects digestion by innervating the organs of the alimentary canal.
Which branch of the ANS is most active during periods of stress or physical activity?
Sympathetic
What are the two mechanisms for regulating autonomic function?
Dual innervation and antagonistic action.
The _______ motor pathways are the body’s “voluntary system”; controlling skeletal muscle and is under conscious control.
Somatic
What are the two major cell types of the CNS?
Glia and neurons
What are the 5 types of Glial cells?
- Schwann - Astrocytes - Oligodendrocytes - Microglial - Ependymal
Which glial cell is the primary glial cell of the PNS?
Schwann cells
What is the primary glial cell of the CNS?
Oligodenrocytes
Oligodendrocytes and Schwann cells are similar because they both…
Provide myelin sheath for neurons.
What is the function of astrocytes?
They are direct communication partners of neutrons, they interact with synapses; uptake and release of neurotransmitters and receptor mediated intracellular Ca2+ signalling. - transport nutrients to neurons - remove debris - guide neuronal development - regulate the space around the synapse - vascular regulation
What glial cell is the equivalent to a macrophage?
Microglia
What are the functions of microglia?
- remove debris - most active following trauma/injury - role in neurodegeneration
What are ependymal cells and what do they do?
Line fluid filled cavities of the brain, often ciliated, that circulate cerebral spinal fluid.
What are the four major sections of the neuron?
- signal reception (dendrites) - signal integration (axon hillock) - signal conduction (axon) - signal transmission (synapse)
What are the general characteristics of neurons?
- post mitotic - do not replicate - oldest cells in body - variable length - maybe replaceable with neuronal stem cells
Which part of the neuron are responsible for receiving an incoming signal?
Dendrites
The ____________ is important in the neuron for integrating input from the dendrites.
Axon hillock
What are the three structural classes of neurons?
- multipolar - bipolar - unipolar
What are the major roles of cell membranes?
- isolate cells from the environment - organize intracellular pathways unto subcellular compartments
What are lipid rafts?
Fluid portions used for organization of the membrane (areas that are high in cholesterol and glycolipids)
What are integral membrane portions?
- tightly bound to the membrane - embedded in bilayer or spanning the entire membrane
What are peripheral membrane proteins?
Weaker associations with the lipid bilayer
The cell body of the membrane is the site of…
- transcription (within the nucleus) - mitochondrial biogenesis
Movement of protein travelling along the axon happens along…
microtubules
_______ are comprised of tubule dimers.
Microtubules
Molecular motors move materials on microtubules, the two types of molecular motors are…
Kinesin and dynein
Which molecular motor moves anterograde-from the cell to the synapse?
Kinesin
Dynein moves _________ the cell body.
Retrograde-towards
Define differences between axons and dendrites.
- axons take info away from the cell body - dendrites are rough (spines) while axons are smooth - there are many dendrites per cell - dendrites have ribosomes and axons do not - axons may have myelin and dendrites cannot - dendrites branch near the cell body.
