Neurobio introduction Flashcards
neurons make up circuits that as a whole are a neural system what are the 3 neural systems and their functions?
sensory systems: brings in information such as the state of organisms and the environment
associational systems: higher orders function of cognition such as perception, memory, attention, emotion, language, and thinking.
Motor system: organize and generate movements and actions
Regulator sequences are made up of promoters and introns what is its functions.
they determine when and where and how readily a gene will be expressed.
scientists such as Camillo Golgi and Santiago Ramon and Charles Sherringtion studied the brain and came up with theories as to how neurons are connected. Name and describe both.
The reticular theory says that the nervous system is not made up of discrete cells but by a web of cells all connected through cytoplasmic links
The neuron doctrine says that the nervous system is made up of discrete cells that communicate at specific points of contact called synapses.
how do neurons work
they receive and transmit information through action potentials.
how do dendrites work
they receive information from other neurons by binding to chemical neurotransmitters from other neurons.
how do axons work
conducts electrical impulses away from a neuron in order to release a chemical neurotransmitter from its terminal.
what are the two types of neurons
local circuit neurons; (interneurons) that have short axons and communicate only with their nearest neighbors.
Projections neurons: have very long axons that communicate to a distant target
what is convergence
a neuron with lots of dendrites ad a lot of dendritic branching will receive more information from many different neurons
what is integration
all of the inputs are summed and contribute to a single output from the axon
what is divergence
although there is typically only 1 axon exiting a neuron cell body the axon can branch to connect to other neurons
synaptic vesicles
membrane-bound structures that contain chemical neurotransmitters and releases neurotransmitters at the synapse to communicate with post-synaptic cell.
synaptic cleft
extracellular space between pre- and post-synaptic surfaces
myelin sheath
insulated (lipid-rich) wrapping around axon
what two cells wrap around the axons
oligodendrocytes or Schwann cells
the soma contains all organelles what do dendrites contain and axons contain
dendrites contain ribosomes and axons contain mitochondria in the axon terminals
nodes of ranvier
patches of uninsulated axon
what courses through the axons and dendrites
microtubules
what does tau do
bundles the microtubules together
what is located at the tip of dendrites and why
actin and because they are actively growing and they can change shapes
what is the functions of dendrite spine on the dendrites
to increase surface area of the dendrite so that more synapses can form.
spiny neurons contain alot or little amounts of spines
alot
does aspinous neurons contain none or alot, or a little spines
none
what do spines of the neurons contain
actin
what is neuromuscular junction
synapses between a motorneuron axon and a muscle cell
what is dystrophin and its function
an intracellular scaffolding protein that links receptors to actin cytoskeleton and localizes them to synapses
what does mutations in the dystrophin gene lead to
leads to muscular dystophy
what do each of these stains do
golgi
fluorescence
nissl stain
golgi- impregnation with silver salts
fluorescence- injection, expression, or immune labeling with fluorescent markers
nissl stain- stain with cresyl violet which marks ribosomes and nucleolus
where are astrocytes located and its function
found in the CNS
function is to maintain ionic and chemical environment of brain for optimal neuronal function
forms the blood brain barrier
forms new synapses
some retain stem cell characteristics
where are oligodendrocytes located and its function
located in the CNS
function is to form the myelin sheath around the CNS axons by wrapping tightly around them
some retain stem cell characteristics
schwann cells have the same function in the PNS
what is the function of microglia
act like brain macrophages
come from hematopoietic stem cells
they clean up debris by phagocytosis from sites of neuronal turnover or injury
when activated will move to site of injury and release cytokines that regulate inflammation
stem cells function
cells that can divide
1 daughter cell remains a stem cell while the other daughter can differentiate into a more specialized cell type
glial stem cells function
can give rise to neurons or glia and have greater potential
why are oligodendrocyte stem cells sometimes called precursors
sometimes called precursors because the other daughter cells will almost become an oligodendrocytes
afferent pathway
a pathway of neurons that carry sensory information toward the brain or spinal chord
local pathway
a pathway of interneurons that convey information between different regions within the brain and spinal chord (receives information from the afferent
efferent pathway
a pathway of neurons that carry motor information or effector information away from the brain or spinal chord to elicit a response
gray matter function
regions within the CNS that have a high density of neuronal cell bodies
nucleus
a collection of neuronal cell bodies that are located deep in the brain
cortex
a sheet of neuronal cell bodies arranged in a layer
white matter
regions within the CNS that contain mostly myelinated axons
tracts
bundles of axons that connect distinct regions within the brain and or spinal chord
commissures
bundles of axons that connect neurons on one side of the brain to the other side
columns
bundles of axons within spinal cord that convey sensory Info to brain or motor info away from the brain
ganglion
collection of neurons that reside in the peripheral nervous system
nerve
a bundle of axons within the peripheral nervous system that travel between a ganglion and a particular target
autonomic branch PNS
not under conscious control, control cardiac muscles, smooth muscles , glands
somatic branch of PNS
under conscious control, controls skeletal muscles
parasympathetic
controls rest and digest functions
sympathetic
controls fight and flight functions
enteric
controls gut motility and secretions
