Bilaminar& Trilaminar Flashcards
________ occurs before completion of oocyte maturation. The____ _____ is released from the ovary and is arrested in _____ of the ____ _____ division. The secondary oocyte is surrounded by the _______ _____ and ____ _____.
- ovulation
- secondary oocyte
- metaphase of the second meiotic division
- zona pellucida
- corona radiata
In order for fertilization to occur, the ___ ____ and ____ ____ must be penetrated by the sperm. What is each layer?
- Zona pellucida: a thin transparent gelatinous layer of protein and polysaccharides
- -Corona radiata : several layers of ovarian follicle
What is capacitation?
Capacitation is the functional changes that sperm undergoin the female reproductive tract that enable them to fertilize a secondary oocyte.
After capacitaion, the overlying sperm ___ ___ becomes unstable when ___ ____ and ____ ___ _____ are removed from plasma membrane overlying the sperm’s _____ (modified ____ ); enzymes are then released (______) or are exposed (____) to help the sperm to penetrate corona radiata and zona pellucida.
- plasma membran
- glycoprotein coat
- seminal plasma proteins
- acrosome
- lysosome
- hyaluronidase)
- acrosin
Steps in Fertilization
First, the Sperm must penetrate the ______ ____ & ____ ____. Next, the fusion of ___ and ____ _____ ____ occurs. When a sperm enters the egg, it triggers changes that prevent _____ which is the _____________________. A _____ reaction occurs and the oocyte membrane becomes _____ to other sperm. The ____ reaction occurs and the Zona pellucida alters its structure to prevent ____ ____ and _____. Next, formation of male _____ occurs; the _____ and ______ of the sperm degrade, so that all mitochondria in the embryo (and all mitochondrial DNA) come from the ____. When sperm is in the egg, the Completion of ___ ___ ___ of oocyte and formation of f___ ____ occurs; the chromatin will ___. Lastly, ____ occurs and ___ _____is formed
- corona radiata and zona pellucida
- sperm and oocyte plasma membranes
- polyspermy
- fertilization of an egg by more than one sperm)
- cortical
- impenetrable
- Zona
- sperm binding and penetration
- pronucleus
- tail and mitochondria
- mother
- f second meiotic division
- female pronucleus
- Unravel
- syngamy
- diploid zygote
What is syngamy?
syngamy-fusion of nuclear material of egg and sperm
Following fertilization, (takes about _-_hrs), the diploid zygote undergoes a series of mitotic cell divisions, called _____, as it migrates toward the uterus. The process of cleavage divides the zygote’s _____ into increasingly smaller cells known as _____ . After the third cleavage, the blastomeres will tightly ____ via _______ &_____ on the surface via a process known as _____.
- 12-24
- cleavage
- blastomere
- cytoplasm
- blastomeres
- align
- tight junctions
- CAMs
- compaction
______- are totipotent which means?
blastomeres- which means they can become any cell or a complete embryo
About 3 days after fertilization, (12-32 cell stage), the embryo is termed a _____ that is made of ______. The morula consists of a ___ ___ of cells with an___ and ____ ____ ____. The morula enters the uterus by day ___.
- morula
- blastomeres
- solid ball
- inner and outer cell mass
- 4
The inner and outter cell masses occur when the cells are a ______. The inner cell mass will become the ______ while the outer cell mass will become part of the ____ part of ____.
- morula
- embryo
- embryonic part of placenta
Fluid from the _____ will penetrate the zona pellucida into the ____ to form a hollow cavity, transforming the ____ into a _____. The inner and outer cell masses are visible now.
- uterus
- morula
- morula
- blastocyst
When fluid from the uterus penetrates the zona pellucida and creates the blastocyst from the morula, the fluid filled cavity separates the blastomeres of the inner and outer cell mass into 2 regions. The outer cell mass is the ____ and the inner cell mass is the _____.
- trophoblast
- embryoblast
The trophoblast makes___ ___ ____ (___) which is the basis for ____ _____; hCG acts on ____ to form ____ ____ so the ovary can make _______ and the pregnancy can be sustain ____ until ____ is developed. hCG increases over time
- human chorionic gonadotropin (hCG)
- pregnancy tests
- ovary
- corpus ludeum
- progesterone
- sustained
- placenta
About 2 days after entering the ____, the blastocyst sheds its ___ ____ and “hatches” allowing the blastocyst to ____. ____ on the outer cell mast has will help it attach to the ____ _____ at its ____ ___ (side where the embryoblast is located)
- uterus
- zona pellucida
- grow
- CAM
- uterine endometrium
- embryonic pole
Abnormal ___ do not usually show any sign of pregnancy because if the trophoblast is defective, no ___ will be produced to support the ___ ___ and pregnancy.
- blastocyst
- hCG
- corpus luteum
Hydatidiform Moles can lead to a ___ ___; these are due to an abnormality in the ____ specifically the ___ that causes the ____ to be overactive and replicated. This usually results in a ____ ____.
Molar pregenacy
abnormal blastocyst
embryoblast
trophoblast
spontaneous abortion
After hatching, in the area over the _______ the trophoblast differentiates into 2 layers: the inner layer is the _____; it consists of ____ _____ with mitotic capacity and helps form part of ____ as well as functions as an _____. The outer ____ zone that forms from the trophoblast is the _________; this zone will invade the _____ ____ to implant the _______; it helps erode the _____ ___ so the ____ can get near the ____ ____ and set up the ____. The synctiotrophoblast will also produces ____ which enters the maternal blood via ______
- embryoblast
- Cytotrophoblast:
- mononucleated cells
- placenta
- anchor
- multinucleated
- synctiotrophoblast
- urterine endometrium
- blastocyst
- uterine wall
- embryo
- uterine wall blood
- placenta
- hCG
- lacunae
Implantation is completed by the end of week ___. The Site of implantation is marked temporaily by a ___/____ ____
2
fibrin(coagulation) plug
If the blastocyst is implanted to close to the internal opening of the ____, then ______ ____ may occur. ______ ____ ____ may occur in the later stages of the pregnancy. A normal, vaginal birth with this type of implantation could increase risk of ____ mom; a _______ may be needed. The baby may be ______.
- cervix
- placenta previa
- painless vaginal bleeding
- hemmorage
- c-section
- premature
If a blastocyst is implanted outside of the uterus it is called and ____ ____. Most of these occur in the ____ ___ (___ pregnancy) which is not viable for the ___ and the _____ will have complications. Ectopic pregnancy
95% of ectopic pregnancies occur in the uterine tube (tubal pregnancy)- not viable for embryo and mom has troubles coming
Signs and symptoms of pregnancy, with abdominal pain and tenderness
May also implant in the abdominal cavity, often in the rectouterine pouch, or pouch of Douglas.
Mom can survive, but fetus usually doesn’t.
- ectopic preg.
- uterine tube
- tubal
- embryo
- mom
*
In week two of development, the embryoblast will differentiates into 2 cellular layers, what are they?
- dorsal epiblast
- ventral hypoblast
The epiblast will eventually become a ____ ____; it goes on to form all of the ____, _____, and _____ layers.
human being
mesoderm
ectoderm
endoderm
The ventral hypoblast (becomes the ____ area) acts as a ____ ____ ___ and eventually goes away.
belly
temporary place holder
Within the epiblast,clefts develop to form the _____ ____ and _____. _____ ____ will migrate and line the inner surface of the _____, forming the exocoelomic membrane (aka _____ _____) which surrounds a space known as the ____ ___ ____.
amniotic cavity and amnion
Hypoblast cells
cytotrophoblast,
Heuser’s membrane
primitive yolk sac
The extraembryonic mesoderm proliferates to fill the space between the _______ and either the _____ or the ____ __ ___ (aka _____).
cytotrophoblast
amnion
primitive yolk sac
primary umbilical vesicle