nsci 2101 - exam one

the name for a zygote 2-3 days after fertilization; latin for mulberry

morula

the time that has passed since fertilization

embryonic age

the time since the last menstrual period

gestational age

defines left and right of the embryonic disk

primitive streak

the three primary germ layers

ectoderm, mesoderm, endoderm

the primary germ layer that forms the nervous system

ectoderm

how does the neural tube close?

starting in the middle and extending rostrally and caudally

what are the three steps of neurulation?

neural plate, neural groove, neural tube

what structure is the source of the PNS?

neural crest

the dorsal side of a developing spinal cord; will later form sensory neurons

alar plate

the ventral side of a developing spinal cord; will later form motor neurons

basal plate

the point that differentiates motor and sensory neurons/alar and basal plates

sulcus limitans

the incomplete closure of the spinal neural tube

spina bifida

incomplete closure of the brain end of the neural tube

anencephaly

what should pregnant women take to reduce the chance of spina bifida?

folic acid (B9)

a thickened plate of ectoderm along the midline of the embryonic disk that gives rise to the neural tube and neural crest

neural plate

tube shaped structure that encloses the developing spinal cord and brain

neural tube

the depressed mid-region from the formation of neural folds in the neural plate

neural groove

the structure formed by the closure of the neural tube

neural crest

the flat inner cell mass where the embryo begins to differentiate

embryonic disk

what are the three primary vesicles?

prosencephalon, mesecephalon, rhombencephalon

what two secondary vesicles does the prosencephalon develop?

telencephalon and diencephalon

what two secondary vesicles does the rhombencephalon develop?

mylencephalon and metencephalon

what secondary vesicle does the mesencephalon develop?

mesencephalon

the bend between the myelencephalon and the metencephalon; this point also opens the fourth ventricle in the brain stem

pontine flexure

the bend in the mesencephalon

cephalic flexure

the bend between the myelencephalon and the spinal cord

cervical flexure

the thick ectodermic area on the neural crest that serves as a precursor to the lens and the eye

lens placode

the thick ectodermic area on the nasal crest that serves as a precursor to the olfactory epithelium

olfactory placode

area containing the cell nucleus; important for synthesizing macronutrients and integrating electrical energy

cell soma

carries nerve impulses away from the soma and to other cells

axon

speeds up impulse conduction on axons

myelin

chemicals that are released at synapses through axon terminals

neurotransmitters

receive synapses from axon terminals

dendrites

sympathetic nervous system

fight or flight systems

parasympathetic nervous system

rest and digest system

axon bundles in the central nervous system

tracts

groups of neurons in the central nervous system

nuclei

groups of neurons in the peripheral nervous system

ganglia

axon bundles in the peripheral nervous system

nerves

back side

dorsal

belly side

ventral

front side

anterior

back side

posterior

toward the beak

rostral

toward the tail

caudal

up

superior

down

posterior

brain section also called “axial”

horizontal

brain section similar to a crown

coronal

brain section that goes vertically through one side

parasagittal

brain section that goes directly through the midline

midsagittal

the most caudal part of the brain

medulla oblongata

the brain area rostral to the medulle

pons

the back of the brainstem

cerebellum

the area between the pons and cerebrum

midbrain

the area rostral to the midbrain

diencephalon

the brain area that controls sensory relay

thalamus

the largest part of the brain, rostral to the diencephalon

telencephalon

grooves on the brain

sulci

bumps on the brain

gyri

the fissure that separates the hemispheres of the brain

intrahemispheric fissure

the sulcus between the pre-central gyrus and the post-central gyrus

central sulcus

the most rostral lobe

frontal lobe

the lobe that is caudal to the central sulcus

parietal lobe

the lobe in the back of the brain

occipital lobe

the lobe that is caudal to the lateral sulcus

temporal lobe

the sulcus between the temporal and frontal lobes

lateral sulcus

the sulcus that is between the frontal and parietal lobes

central sulcus

lateral apertures that provide a way for the cerebrospinal fluid to drain from the brain’s ventricular system into the subarachnoid space

foramen of luschka

the outermost layer of the meninges that adheres to the skull and is innervated by pain nerve fibers; it also has it’s own blood supply through the meningeal arteries

dura mater

the middle layer of the meninges that lies between the dura and pia; has a stringy, spiderweb-like appearance

arachnoid mater

the innermost layer of the meninges that is the thinnest and adheres to the surface of the brain

pia mater

the dural fold that lies in the interhemispheric fissure to prevent movement of the hemispheres laterally

falx cerebri

the dural fold that reduces movement of the posterior brain, including the cerebellum

tentorium cerebelli

the largest ventricles, lying within the telencephalon; there is one in each hemisphere of the brain

lateral ventricles

the ventricle that lies on the midline and separates the two halves of the diencephalon

third ventricle

the thin ventricle that moves through the dorsal midbrain to connect the third and fourth ventricles

cerebral aqueduct

the ventricle that lies on the dorsal surface of the pons and part of the medulla

fourth ventricle

cells that reside in the ventricles (not aqueduct) and are responsible for making most of the cerebrospinal fluid in the body

choroid plexus

structures that allow the cerebrospinal fluid to drain from the subarachnoid space into the venous system

arachnoid granulations

a condition where there is excess CSF in the head, causing the skull of an infant to enlarge and swell

hydrocephalus