Embryology Flashcards
How is a zygote formed?
When the sperm binds to the oocyte receptor (fertilisation)
Where does fertilisation occur?
In the uterine tube
What is capacitation?
Maturation of sperm motility
What is the structural difference between a morula and a blastocyst?
Morula = solid ball of identical cells
Blastocyst = hollow ball of cells
What does the trophoblast become?
Placenta
Name the outer layer of the oocyte
Zona pellucida
Acrosomal reaction involves…
A release of enzymes to break through the zona pellucida
A zygote becomes a ____, then develops into a blastocyst
Morula
How does the inner cell mass of a blastocyst become an embryo?
Via cell differentiation
Describe cleavage in mitotic division
Rapid cell division of a zygote without growth
A pluripotent cell can…
Differentiate into any cell type of the embryo proper (ie. germ layers)
A multipotent cell can…
Differentiate into closely related cells; limited
An oligopotent cell can…
Differentiate into a few cell types
A totipotent cell can…
Differentiate into any cell type
The layers of the bilaminar disc are…
The hypoblast and epiblast
What is neurulation?
The formation of the CNS, where the neural plate forms the neural tube
What happens when the tube fuses?
The neural crest cells detach to form the PNS
Embryonic folding occurs at the ___ week of development
4th
Gastrulation of a blastocyst is…
Differentiation of the epiblast of the bilaminar disc to form three layers
What shape does the flat trilaminar disc fold into?
A cylinder
Name the three layers of the ‘cylinder’
Endoderm, mesoderm, ectoderm
The endoderm is a precursor to…
The gastrointestinal tract (GIT)
The mesoderm is a precursor to…
The musculoskeletal & circulatory system
The ectoderm is a precursor to…
Tooth enamel, epidermis & accessory structures
What is a placode?
An embryonic structire that gives rise to other structures
Pharyngeal arches or branchial arches contain what two features?
A cranial nerve and vasculature
The stomatodeum forms…
The mouth
What structures does the first branchial arch form?
The mandibular and maxillary arch
Name the cartilaginous structure of the first branchial arch
Meckel’s cartilage
