Embryology, public health and human factors Flashcards
Conceptus
fertilisation –>week 3
Embryo
week 4–>week 8
Foetus
week 9–>birth
Gametogenesis
germ cell formation
Fertilisation
fusion on sprerm and oocyte to form zygote
cleavage
rapid period of cell division
Gastrulation
formation of germ layers
Ecto (outer)
Meso (middle)
Endo (inner) -derm
Formation
embryonic folding
Organogenesis
formation of organs and organ systems
major processes in embryology
Cell division, differentiation, cell attachment, apoptosis, induction, migration
how development of the embryo is regulated
Genetic, Epigenetic (preferential expression of either the maternal or the paternal copy of a gene), environmental.
where does fertilisation take place
ampulla
Cleavage
the zygote (sperm + oocyte) undergoes series of mitotic divisions which leads to many daughter cells called blastomeres. When there are 8 cells compaction takes place so that the zygote becomes a Blastocyst.
implatation occurs where
middle or upper uterine wall
if implantation takes place in the overy, ampulla or uterine tube what can happen
ectopic pregancy
ectoderm
epidermis of skin and nervous system
mesoderm
subdivided
endoderm
linig of gut tube, linig of resp tree
The embryo is most at risk of defects occurring during weeks 3 - 8
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when does the heart start to develop?
week 4
Interatrial septum separates the right from the left atrium in the adult heart and that incomplete closure of the embryonic foramen ovale in the septum leads to an atrial septal defect (ASD).
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The interventricular septum separates the right from the left ventricle in the adult heart. Know that incomplete closure leads to a ventricular septal defect (VSD
..
abnormalities of the heart?
- transposition of the great vessels (where aorta emerges from right ventricle, and pulmonary trunk from left)
- tetralogy of Fallot (pulmonary stenosis, right ventricle hypertrophy, VSD, overriding aorta)
what is incidence?
No. of new cases of a disease occurring in a population during a specific period of time/
No. of persons exposed to risk of developing the disease during that period of time
ie the occurrence, rate, or frequency of a disease
what is prevalence
No. of cases of a disease present in population at specific point in time /
No. of persons at risk of having disease at that point in time
ie the fact or condition of being prevalent; commonness.
