Test 2: Lab Vocab Flashcards
Activation:
Initiation of development/exit from meiotic arrest of an oocyte due to
stimulation such as sperm fusion.
Acrosome
caplike saccular organelle, derived from the Golgi apparatus, containing
the proteolytic enzymes that allows the sperm to penetrate the zona pellucida (egg’s
extracellular matrix).
Acrosome reaction
the process by which the acrosome releases its proteolytic
enzymes to assists the sperm to penetrate the zona pellucida and fertilize the egg.
Adult stem cell:
unspecialized cell that is present in a differentiated (specialized)
tissue, renews itself, and can differentiate to yield specialized cell type(s) of that tissue
type.
Allantoic stalk
a canal in the umbilical cord connecting the cloaca, then later the
urogenital sinus with the allantois. Carries urine.
Allantois
extraembryonic membrane of amniotes, grows out of the hindgut and fuses
with the chorion; it contributes to the placenta of mammals.
Amnion
an extraembryonic membrane of amniotes that encloses the embryo and
amiotic fluid; usually arises from folds of somatopleure.
Amphimixis:
fusion of male and female pronuclei.
Androgenetic
being derived from the paternal genome.
Anencephaly
developmental abnormality, incomplete development of cerebral
hemispheres and cranium.
Anterior visceral endoderm (AVE)
in the mammalian embryo, the AVE is an important
signaling center essential for head structures formation that appears opposite to the
primitive streak at the time of implantation.
Aortic arches:
These begin as symmetrically arranged, paired vessels that develop
within the paired pharyngeal arches and link the ascending and descending/dorsal paired
aortae. Some arches degenerate. Left aortic arch IV becomes the Arch of the Aorta and
aortic arch VI is the ductus arteriosus on the left.
Aortic sac
formed from the fusion of the ventral aortae, ventral to the pharynx. The
aortic arches arise from the aortic sac.
Aplasia
congenital absence of an organ (renal aplasia)
Appendicular:
referring to the appendages/limbs (in contrast to axial which refers to
the spinal column and ribs). Note: tail would be axial, not an appendage
Archenteron:
the “primitive gut,” the innermost tube of an embryo; lined with
endoderm, it will become the digestive tract.
Atresia
congenital absence of an opening or lumen (atresia ani, atresia coli)
Atria
left and right) the heart chamber that in the embryo receives blood from the
sinus venosus and delivers it to the ventricle.
Autologous:
derived from self.
Branchial arch/cleft/pouch
see pharyngeal arch/cleft/pouch. “Branchial” refers to the
gill system found in fish and does not really apply to terrestrial animals.
Bulbar ridges:
Spiral thickenings of the bulbis cordis. Their fusion divides the bulbus
cordis into the aorta and the pulmonary trunk.
Bulbus cordis (conus truncus)
he heart chamber, originally most cranial in position,
connecting the ventricle with the ventral aorta (and later, the aortic sac).
Cloaca
The caudal chamber of the digestive tract. It receives the allantoic stalk, urinary
ducts, and reproductive ducts. In mammals it is partitioned to form the rectum, urinary
bladder, and the urogenital sinus.
Cloacal membrane
caudal end of the primitive streak formed by closely apposed
endoderm and ectoderm, future site of the anus.
Cranial nerve V:
(trigeminal nerve)
a pair of mixed nerves arising from the sides of the
metencephalon and semi-lunar ganglia; three divisions-the ophthalmic, maxillary and
mandibular rami-innervate the mandibular arch region.
Cranial nerve VII:
(facial nerve)
pair of mixed nerves arising from the myelencephalon
at the cranial margin of the otic vesicles and from the geniculate ganglia; they innervate
branchial arch 2.
Cranial nerve VIII:
(vestibulocochlear nerve)
a pair of sensory nerves arising from the
auditory ganglia; they innervate the otic vesicles.
Cranial nerve IX:
(glossopharyngeal nerve)
a pair of mixed nerves arising from the
myelencephalon at the caudal margin of the otic vesicles; and bearing the superior and
petrosal ganglion; they innervate branchial arch 3.
Cranial nerve X:
(vagus nerve)
pair of mixed nerves arising from the myelencephalon
and bearing the nodose and jugular ganglia; the innervate branchial arches 4, 5, and 6,
and extend parasympathetic fibers to the viscera. In aquatic vertebrates they innervate
the lateral line.
Cranial nerve XII:
(hypoglossal nerve)
A pair of nerves arising from many rootlets on
the ventral wall of the myelencephalon; they innervate the tongue muscles.
Descending aorta:
he principal artery of the trunk; a median vessel formed by the fusion
of the paired dorsal aortae; it extends from the subclavian to the common iliac arteries.
Diencephalon:
The caudal division of the prosencephalon to which the optic stalks and
epiphysis attach. Its cavity is the third ventricle of the brain. It forms the epithalamus,
thalamus, and hypothalamus. Its roof forms the choroid plexus.
Diverticulum:
Outpouching of a hollow (or a fluid filled) structure in the body. Example:
respiratory system formed from a diverticulum off of the foregut.
Dorsal aortae:
The primitive, paired, longitudinal arteries of the trunk that fuse together
caudal to the pharynx to form the descending aorta. In the pharyngeal region they
contribute to the external carotid arteries, descending aorta, and in mammals the right
subclavian artery.
Dorsal root ganglia
=spinal ganglia) sensory ganglia derived from the neural crest
lying laterally paired and dorsally to the spinal cord (in the embryo found ventral to the
spinal cord). Connects centrally with the dorsal horn of the spinal cord.
Ductus arteriosus:
forms from left aortic arch VI, serves as a shunt between the
embryonic/fetal pulmonary artery and the descending aorta. It normally closes at birth (if
not, pathological condition is called patent ductus arteriosus).
Ductus venosus
a vein in the liver of amniotes carrying blood from the vitelline and left
umbilical veins to the sinus venosus; it derives from the vetilline veins; allows oxygenated
blood from the placenta to shunt directly to the heart and it is obliterated after hatching in
birds or after birth in mammals.
Endocardial cushion
a pair of connective tissue outgrowths that undergo fusion to
divide the atrioventricular canal; it contributes to the atrioventricular valves.
Epaxial
Originally referring to the part of a fish’s body dorsal
to the centrally-located lateral line that runs the length of the body. In terrestrial animals,
this is the area dorsal to the transverse processes of the spine. Epaxial muscles are the
dorsal muscles of the back including the iliocostalis, longissimus, and transversospinalis system
Fistula:
abnormal connection or passageway between organs or vessels that normally
do not connect. Example: bronchoesophageal fistula.
Foregut:
the anterior portion (from the tracheobronchial diverticulum to the liver bud) of
the forming gastrointestinal tract (fore-, mid-, hind-), blood supply is from the Celiac artery,
will form esophagus, crop (birds), stomach, proximal half of duodenum, liver, biliary tract,
and pancreas.
Ganglion of Cranial Nerve V
Semilunar ganglion.
Ganglion of Cranial Nerve VII:
Geniculate ganglion.
Ganglion of Cranial Nerve VIII
Auditory ganglion.
Ganglion of Cranial Nerve IX
Superior ganglion and Petrosal ganglion.
Ganglion of Cranial Nerve X:
Jugular ganglion and Nodose ganglion.
Hypaxial
(hypo=under, axis=center line): Originally referring to the part of a fish’s body
ventral to the centrally-located lateral line that runs the length of the body. In terrestrial
animals, this is the area ventral to the transverse processes of the spine. Hypaxial
muscles include the subvertebral muscles (psoas muscles), flank muscles (external and
internal oblique and transverse), and the rectus abdominus.
Infundibulum
a ventral evagination of the prosencephalon: it lies in the floor of the
diencephalon and forms the neural lobe of the hypophysis (pituitary gland).
Intersegmental arteries
Originally small paired branches of the dorsal aortae arising
between the somites. They contribute to the vertebral, subclavian, intercostal, and
lumbar arteries.
Interventricular foramen
an opening in the ventricular septum allowing blood to cross
between the right and left ventricles; it closes during division of the conotruncus and the
atrioventricular canal.
Interventricular septum
muscular partition arising from the caudal wall of the primitive ventricle; it grows cranially, fuses with the endocardial cushion and the bulbar
septum and divides the ventricle into the right and left ventricles.
Meckel’s Cartilage
derived from the ventral part (Mandibular Arch) of Pharyngeal Arch I, it provides shape for the mandible as it forms, and then Meckel’s cartilage mostly degenerates except for two small parts at the dorsal end that form the incus and malleus
of the ear.