Embryology Flashcards
(46 cards)
The name given to the Embryonic components of the placenta
Chorion Frondosum
The name give to the maternal components of the placenta
Decidua Basalis
Define Decidua:
Endometrial lining of uterine cavity.
Define Decidua Basalis:
Portion of endometrium underlying the implantation site.
Define Decidua Capsularis:
Portion overlying the implanted embryo
Decidua Parietalis:
The remainder of the endometrium
What does DB stand for?
Decidua Basalis (part of the placenta)
What does DP stand for?
Decidua parietalis
What does DC stand for?
Decidua Capularis
Decidua Capsularis
Portion overlying the implanted embryo and separating it from the uterine cavity. It is eventually lost as the amniotic cavity enlarges & occupies all the cavity
Chromatid
One of the two strands of a chromosome joined together by a centromere
Chromosomal Crossover
An important set in genetic recombination in which two chromosomes, normally homologous (functionally the same), pair up and exchange DNA. The shuffling of genes is called independent assortment
The parent of stem cells that produce sperm are called
Spermatogonia
What are the stages in spermatogeneis
- Spermatogonium
- Primary Spermatocyte
- Secondary Spermatocytes (meiosis I)
- Spermatids (meiosis II)
- Spermatozoa
What are the stages in Oogenesis
- Oogonium
- Primary Oocyte
- Secondary Oocyte (meiosis I)
- Ootid (meiosis II)
- Ovum (differentiation)
Define Aneuploidy
Numerical error in chromosome division. Too many or too few.
Define NonDisjunction
The process of separation of homologous chromosome pairs fails.
(e.g) Trisomy disorders, named for chromosomes involved
What is the genotype for Klinefelter
47 XXY
What is the genotype for Turner’s Syndrome?
45 XO
Define Teratogens
External agents (extrinsic to the fetus) that produce developmental Malformations.
Give a few examples of potential Teratogens
Radiation, prenatal infections, temperature extremes, prescription drugs/dietary supplements, Mechanical forces
Major events of Embryogenesis
Cleavage: Division of zygote & formation of blastocyst
Gastrulation: Formation of Germ Layers
Organogenesis: Germ layers differentiate so as to give rise to all organs in the human body
What is the fetal period?
Includes the remaining weeks of development prior to birth (weeks 9-38)
The fetus continues to grow
It’s organs increase in complexity
What steps are involved leading up to the the “Morula”
Before the 8-cell stage, cells are not tightly bound together, but after the third cleavage division, then they become more compact and form a ball called the morula.