Vocabulary - Fertilization and implantation Flashcards
process by which male and female gametes fuse
fertilization
mitotic cell division of the zygote
cleavage
cleavage of zygote to 32 or more cells
morula
outer cell mass of morula giving rise to the placenta
trophoblast
fertilized egg implanting into the endometrium; fluid-filled central cavity formed by morula
blastocyst
cell line that gives rise to the gametes; originate in the yolk sac at 4th week of development; migrate to presumptive gonadal region
primordial germ cells
proliferation of primordial germ cells leads to … (compact strands of tissue)
primitive sex cords
swelling of primitive sex cords leads to …
genital ridges; primordial gonads
a single layer of follicle cells surrounding primary oocytes
primary follicle
mass of cells found in empty follicle stimulated by LH hormone; maintains the pregnancy state (endometrial wall); secretes progesterone for 11-12 weeks of embryonic development
corpus luteum
removal of glycoprotein coat and seminal proteins from acrosome (head of sperm)
capacitation
glycoprotein shell of oocyte
zona pellucida
during cleavage, these cells are called …
blastomeres
blastomeres in the center of the morula; gives rise to embryo/organs
inner cell mass
blastomeres in the periphery of the morula; gives rise to placenta
outer cell mass
embryo proper (created by inner cell mass) is called …
embryoblast
placenta (created by outer cell mass) is called …
trophoblast
structure with fluid-filled cavity derived from morula 4 days post fertilization that breaks free from zona pellucida and implants into uterine wall
blastocyst
hormone secreted after successful implantation; supports corpus luteum and supplies progesterone
human chorionic gonadotrophin (hCG)
abnormal site of implantation due to “burrowing capabilities” of blastocyst
ectopic pregnancy
2 layers of embryoblast
epiblast (primary ectoderm) and hypoblast (primary endoderm)
remnants of epiblast and hypoblast; lies between amniotic cavity and blastocyte cavity; cells develop into embryo proper
bilaminar disc
invades endometrium and pulls blastocyst into the uterine wall 7 days post fertilization
syncytiotrophoblast
where do the primordial germ cells differentiate into sperm and oocyte?
the developing gonads
what type of sex cords do males have?
medullary sex cords
what type of sex cords do females have?
cortical sex cords
what is the role of testosterone in male development?
1) activate the primordial germ cells
2) stimulate growth of the testis
3) mature the seminiferous tubules
4) induce spermatogenesis
where does testosterone originate from?
testis
used to determine “ovarian reserve”; visible on ultrasound; indicative of the number of primordial follicles remaining
Antral Follicle Count
what is a low AFC (Antral Follicle Count) indicative of?
infertility; low egg supply
what is a high AFC (Antral Follicle Count) indicative of?
fertility; high egg supply
how can a women increase her chances of getting pregnant?
1) monitor body temperature
2) cervical mucus production
3) LH levels
when is a woman’s most fertile period?
several days before and no more than one day after ovulation
what is the purpose of the menstrual cycle?
1) produce a mature egg to be fertilized
2) prime the uterus
which hormone stimulates ovulation (egg release)
LH (ovulation-stimulating hormone)
identical twins joined in utero
and are typically classified by the point at which their bodies are joined.
conjoined twins
occur when a twin embryo begins developing in utero, but the pair does not fully
separate, and one embryo maintains dominant development at the expense of the other
parasitic twins
what stage of meiosis is the egg in at ovulation?
meiosis II
which endocrine structures release hormones?
hypothalamus; anterior pituitary gland
gonadotrophin-releasing hormone stimulates which 3 hormones?
gonadotrophin, FSH, and LH (leads to ovulation)
