Exam II Flashcards
The process by which the bilaminar disc is converted to a trilaminar disc
Gastrulation
This process marks the beginning of morphogenesis.
Gastrulation
What genes play a role in gastrulation?
Shh (sonic hedgehog) and Wnts
Epiblast cells proliferate on the midline of the disc and form a narrow streak that runs down the disc. This structure is known as what?
Primitive streak
This structure is located in the middle of the primitive streak.
Primitive groove
This structure is located at the end of the groove in the primitive streak.
Primitive pit
This embryonic layer is formed when epiblasts stay on the top layer of the embryo.
Ectoderm
This embryonic layer is formed by the migration of epiblasts through the primitive groove into the middle layer of the embryo.
Mesoderm
This embryonic layer is formed when epiblasts displace the hypoblasts in the lower layer of the embryo.
Endoderm
What are the three layers of the gastrula?
Ectoderm, mesoderm, and endoderm
The prechordal plate (forms the mouth) develops at this end of the embryo
Cranial end
The cloacal plate (future anus, urinary, and genital tracts) develops at this end of the embryo.
Caudal end
This is the area where the future heart will develop.
Cardiogenic area
What is the most common tumor in newborns?
Sacrococcygeal teratoma
This midline cord of cells is formed from mesoderm, which was previously formed at the primitive node, migrating cranially.
Notochord
The notochord grows until it reaches what?
Prechordal plate
This is the small portion of the notochord, which persists after the majority disappear.
Nucleus pulposus
This the formation of vascular channels
Vasculogenesis
This is the formation of vessels
Angiogenesis
This structure consists of a core of cytotrophoblasts covered by syntrophoblasts.
Primary chorionic villi
This structure consists of mesodermal cells penetrating the core of the cytotrophoblasts of the primary villi.
Secondary chorionic villi
This structure is used to describe the mesodermal core differentiating into blood and blood vessels.
Tertiary chorionic villi
This the process of gene expression or silencing.
DNA methylation
Cell lineage studies have shown epiblasts being what?
Pluripotent stem cells
What genes play a role in the development of handed asymmetry?
Nodal genes
The notochord is the primary inducer of the overlying ectoderm to form what?
The neural plate
The process of converting the neural plate into the neural tube (happens in the 4th week)
Neuralation
The newly formed neural canal communicates with the amniotic cavity through large openings called the…
Cranial and caudal neurophores
The edges of the neural fold make contact on which day of development?
22nd
The neurophores close by which day of development?
26th
Interruption of neural tube closure can lead to which conditions?
Spina bifida and anencephaly
These cells develop bilaterally along the borders of the neural tube and can differentiate into a number of different cell types.
Neural crest cells
On each side (paraxial) of the notochord and neural tube in the mesoderm layer thickened areas form. These areas become what?
Paraxial mesoderm
Lateral area: Lateral mesoderm
Between the two areas of mesoderm: Intermediate mesoderm
These are segmented mesodermal tissue (paraxial) along the neural tube, which gives rise to the vertebral column, voluntary muscle, connective tissue, and skin.
Somites
This is the process of developing organ systems.
Organogenesis
The nervous system, neural crest cells, sensory epithelium, epidermis and derivatives, and the pituitary gland are all derivatives of what germ layer?
Ectoderm
The axial region, paraxial region, intermediate region, and lateral region are all derivatives of what germ layer?
Mesoderm
The lateral region of mesoderm differentiates into two additional layers of mesoderm. What are they and which germ layer is each one closer to?
Splanchnic (closer to the endoderm) and somatic (closer to the ectoderm) mesoderm
Blood and blood vessels, heart, lymphatic, cardiac, and visceral muscles as well as the adrenal cortex are all derivatives of what mesodermal layer?
Splanchnic mesoderm
The skull and muscles of the head are derived from what mesodermal layer?
Somatic mesoderm
The respiratory system, digestive systems, liver, pancreas, thyroid and parathyroid are all derivatives of what germ layer?
Endoderm
The study of the fetus and newborn-as patient. From 22 weeks after fertilization viability to 4 weeks after birth.
Perinatology