term 1 Flashcards
what is the difference between radially and bilaterally symmetrical animals?
radially have a nervous system composed of a network of cells distributed through the body, and bilaterally have segregated and very defined nervous system.
what is the ration of neurons to glial cells?
10:1
what are the stonger points of development in each hemisphere?
left side: speech, writing, main language center, calculation, right visual field projection
Ride side: spatical perception, word comprehension, non-verbal concept formation, left visual field projection.
what is the plane that divides the front and back?
frontal (coronal) plane
what is the plane that divides the rights and left?
sagittal plane
what is the plane that divides the top and body of the body?
transverse (horizontal) plane
what is the terminology for sensory and motor nerves?
sensory is afferent (towards CNS)
motor is efferent (away from CNS)
*may not be specific for the type of nerve, but the direction instead
what is the terminology if the nerve is on the same side? opposite?
same side: ipsilateral
opposite: contralateral
what is the name for the anterior and posterior parts of the body?
anterior: ventral
posterior: dorsal
what is the name for the left and right side of the body?
left is medial and right is isteral
what is the name for the top and bottom of the body?
top is the rostral AND bottom is the cotal
what contains the seonsry neurons?
white matter
what contains the cell bodies?
gray matter
what do the sensory and motor neurons come through to get to the central cannal of the spinal cord?
sensors come through the dorsal, motor cell body neurons come through the ventral horn.
where do cell bodies stay?
in the dorsal horn.
what are the 5 steps to the normal CNS development?
- induction
- neural tube formation
- regionalization and specific of the neural tube
- proliferation and migration
- connection and selection
what is happening during the primary neurulation?
neural plate bends and begins to fold up. this creates neural groove. the folding continues and the crest cells sandwich between epidermis and neural tube. eventually the tube completely closes.
what are sulcus liminants?
longitumal group in spinal cord wall. it seperates the wall neurons into two groups alar and basal
what is the alar plate?
in the dorsal location this forms the sensory area >posterior horn.
migration of the plate forms the dorsal root ganglia
what is the basal plate?
in the ventral location this forms the motor area> ventral nerve roots.
motor axons grow from this plate
what is lumen?
ventricular system (and its full of CSF)
what two things can go wrong during brain development of the fetus>?
- congenital malformations: congenital abnormalities, array of severity
- spinal bifida: defective closure of the neural tube, a bump forms along the spinal cord (usually lower back)
how are caudate and lentiform nucei formed?
from splitting of the corpus striatum by the fibers projecting directly from the cerebral cortex and from the thalamus to the cortex
what is the result of further expansion of the cerebral hemispheres?
brainstem-restricted to the remaining ‘free parts’ (midbrain-pons-mendulla)
at week 28 what is a major process?
several sulci (grooves) appear on the brain surfface
what does a bi lipid bilayer do?
it serves as a barrier against the movement of water molecules and water soluble substances.
what are transmembrane proteins?
they allow transport across the membrane; provide an alternate path into and out of the cell
what are the two major groups of transmembrane proteins?
channel proteins and carrier proteins.
describe channel proteins
they have a central pore that permits passage of ions across the membrane. It is selective for the ion it moves K+ Na+ and cl=
describe carrier proteins
they faciliate diffusio of molecules; undergo conformational change to bring the molevule accross the membrane
its highly selective in the types of molecules and ions they allow to cross
name the 2 mechanism of transport across the membrane.
diffusion: osmosis, [gradient]
the facilitated diffusion: polar or charges molecules and substances that cont diffuse
active transport: movements of ions agasint a [gradient] ATP required.
gating of protein channels are controlled in two ways, what are they?
- voltage gating where the gate responds to an electrical potential accross the membrane
- chemical gating- gate opens in response to binding of a chemical messenger.
what is the axon hillock?
its located where the acon emerges form the cell body. its the site of AP initiation. High [Na+ channels] and one triggered Ap propogates as a wave along the axon.
what is the refractory period?
it allows for unidirectional propogation of AP
what is the role of myelin in an AP propogation?
its a saltatory conduction. it increases the velocity of nerve transmission and conserves energy.
what is multiple sclerosis?
it is the demyelinization of the nerve cells.
what is a synapse?
the specialized junciton where neruons comminicated with eachother or a target cell.
name the 2 specific types of synapses.
- withiin a neuron and the signal is transmited electrically.
- between neurons information travels chemically (neurtransmitters)
what are the 3 elements (anatomy) of a synapse?
pre-synaptic cell >synaptic celf<post-synaptic cell.
explain the neuro transmitter glutamate
A.A. most common in CNS,
mediates excitatory signals
involved in cognition, memory, learning
explain the neurotransmitter GABA
A.A. major inhibitory NT
highly concentrated in the basal ganglia, hypothalamus, hippocampus
responsible for muscle tone regulation
explain the neurotransmitter Acetylcholine
biogenic amine
involved in learning and memory
degeneration =alzheimers’ disease