Ovulation To Implantation Flashcards
It controls the 💡sexual cycle among females.
HYPOTHALAMUS
A hormone produced by the 💡hypothalamus, acts on cells of the 💡anterior lobe (adenohypophysis) of the pituitary gland, which in turn 💡secrete gonadotropins.
Gonadotropin- releasing hormone (GnRH)
These are hormones secreted by the 💡anterior pituitary gland that 💡stimulate and 💡control cyclic changes in the ovary.
Follicle-stimulating hormone (FSH) Luteinizing hormone (LH)
At the beginning of each ovarian cycle,__ are stimulated to grow under the influence of FSH
15 to 20 primary-stage (preantral) follicles
Functions of FSH during the ovarian cycle includes:
- Protects the 15-20 preantral follicles from dying and becoming atretic.
- Stimulates maturation of follicular (granulosa) cells surrounding the oocyte
How many of the preantral follicles reaches maturity during the ovarian cycle:
ONE Preantral Follicle
What will happen to the preantral cells that did not reach full maturity?
They will degenerate and become atretic.
A 💡connective tissue that replaces the 💡degenerated oocyte and surrounding follicular cells when a follicle becomes atretic.
Corpus Atreticum
Mediates the 💡proliferation of follicular (granulosa) cells.
Growth Differentiation Factor 9
A cell that produces 💡androstenedione and testosterone
Theca Interna
A cell that 💡converts androstenedione and testosterone to estrone and 17 Beta-estradiol
GRANULOSA CELLS
Estrogen function during the ovarian cycle:
💡💡
Endometrium
Cervix
Anterior pituitary gland
■ The uterine endometrium enters the follicular or proliferative phase.
■ Thinning of the cervical mucus occurs to allow passage of sperm.
■ The anterior lobe of the pituitary gland is stimulated to secrete LH.
Effect of LH surge during the midcycle;
💡💡
Meiosis
Progesterone
Ovulation
■ Elevates concentrations of maturation- promoting factor, causing oocytes to complete meiosis I and initiate meiosis II
■ Stimulates production of progesterone by follicular stromal cells (luteinization)
■ Causes follicular rupture and ovulation
Under the influence of (1)__, the(2)__ grows rapidly to a diameter of 25 mm to become a (3)__.
(1) FSH and LH
(2) vesicular follicle
(3) mature vesicular (graafian) follicle
Abrupt increase in LH causes the primary oocyte to complete __ and the follicle to enter the preovulatory mature vesicular stage
meiosis I
Meiosis II is also initiated, but the oocyte is arrested in (1)__ approximately (2)__ before ovulation.
(1) metaphase
(2) 3 hours
The high concentration of LH increases __, resulting in digestión of collagen fibers surrounding the follicle.
collagenase activity
An arachidonic acid derivative that increases in response to the LH surge and cause 💡local muscular contractions in the ovarian wall which causes extrusion of oocyte.
Prostaglandin
This form when some of the 💡cumulus oophorus cells rearrange themselves around the zona pellucida
Corona Radiata
It is formed under the influence of LH .
It is formed when cells of theca interna and granulosa undergoes 💡hypertrophy and lipids accumulates becoming lutein cells (yellow pigment).
It secretes 💡progesterone until the end of 4th month.
Corpus Luteum
A hormone secreted by 💡corpus luteum that causes the uterine mucosa to enter the progestational or secretory stage in preparation for implantation of the embryo.
Progeterone
In humans, the fertilized oocyte reaches the uterine lumen in approximately __.
3 to 4 days
If fertilization does not occur, the corpus luteum reaches máximum development approximately __ after ovulation.
9 days
A process of lutein cell degeneration causing the corpus luteum to shrink.
Luteolysis
A slight pain some women feel during ovulation because it normally occurs near the middie of the menstrual cycle.
Mitteischmerz [Germán for “middie pain”)
A mass of fibrotic scar tissue that formed when corpus luteum degenerates.
Corpus Albicans
Happens when corpus luteum degenerate as well the decrease in progesterone production.
Menstrual Bleeding
A hormone that prevents the degeneration of the corpus luteum when the oocyte is fertilized.
Human Chorionic Gonadotropin
A cell that secretes human chorionic gonadotropin
Syncytiotrophoblast (placenta)
It is form when corpus luteum continues to grow.
Corpus Luteum of Pregnancy (corpus luteum graviditatis)
Yellowish luteal cells continué to secrete progesterone until the end of the __
fourth month
Removal of the corpus luteum of pregnancy before the fourth month usually leads to __.
abortion
The process by which male and female gametes fuse.
FERTILIZATION
It is the site where fertilization occurs.
Ampullary región of the uterine tube
Only __ of sperm deposited in the vagina enter the cervix, where they may survive for many hours.
1%
The trip of sperm from cervix to oviduct can occur as rapidly as (1)__ or as slow as (2)__.
(1) 30 minutes
(2) 6 days
How long will b the usual trip of sperm from cervix to oviduct
2-7 hours
After reaching the __, sperm become less motile and cease their migration
Isthmus
Spermatozoa are not able to fertilize the oocyte immediately upon arrival in the female genital tract but must undergo:
- Capacitation
2. Acrosome reaction
It is a 💡period of conditioning in the uterine tube and involves epithelial interactions between the sperm and the mucosal surface of the tube that in the human lasts approximately 7 hours.
It is a process of removal of the glycoprotein coat and seminal plasma proteins from the plasma membrane that overlies the acrosomal region of the spermatozoa.
Capacitatíon
Only __ can pass through the corona cells and undergo the acrosome reaction.
Capacitated sperm
The release of 💡cortical granules enzyme will close the zona pelucida to prevent sperm binding and penetration.
Cortical and zona reaction
It occurs after 💡binding to the zona pellucida and is 💡induced by zona proteins.
This reaction culminates in the release of enzymes needed to penetrate the zona pellucida, including 💡acrosin- and trypsin-like substances
Acrosome reaction
It is a 💡glycoprotein shell surrounding the egg that 💡facilitates and maintains sperm binding and induces the acrosome reaction.
ZONA
It is a 💡zona protein that mediates both 💡binding and the 💡acrosome reaction.
Ligand ZP3
An 💡acrosomal enzyme that 💡allows sperm to penetrate the zona, thereby coming in contact with the plasma membrane of the oocyte.
ACROSIN
Three Phases of Fertilization:
Phase 1, penetration of the corona radiata
Phase 2, penetration of the zona pellucida
Phase 3, fusión of the oocyte and sperm cell membranes (important phase)
It 💡lines the plasma membrane of the oocyte that 💡releases lysosomal enzymes that 💡result in the contact of head of the sperm comes in contact with the oocyte surface.
Cortical granules
__ of the zona pellucida changes when the head of the sperm comes in contact with the oocyte surface.
Permeability
Penetration of 💡more than one spermatozoon into the oocyte.
Polyspermy
One of the daughter cells, which 💡receives hardly any cytoplasm.
Second polar body
In the human, both the (1)__ enter the cytoplasm of the oocyte, but the plasma membrane is left behind on the (2)__.
(1) head and the tail of the spermatozoon
(2) oocyte surface
It is formed when the 💡spermatozoon nucleus becomes swollen as it moves forward until it 💡lies clóse to the female pronucleus.
Male pronucleus
Three ways of egg response when the spermatozoon has entered the oocyte:
- Cortical and zona reactions.
- Resumption of the second meiotic división.
- Metabolic activation of the egg
Vesicular nucleus where its chromosomes (22 plus X) arrange themselves
Female pronucleus
Morphologically, the male and female pronuclei are __
Indistinguishable
During growth of male and female pronuclei (both haploid), each pronucleus must __.
replícate its DNA
Main results of the fertilization:
- Restoration of the diploid number of chromosomes
- Determinatíon of the sex of the new individual.
- Initiation of cleavage.
It is a 💡16 cell compacted embryo that resembles 💡mulberry.
Morula Cell
Inner cells of the mórula constitute the (1)__, and surrounding cells compose the(2)__.
(1) inner cell mass
(2) outer cell mass.
It gives rise to tissues of the 💡embryo proper.
Inner Cell Mass
It forms the 💡trophoblast, which later contributes to the placenta.
Outer Cell Mass
-
Blastomeres
A process where blastomeres maximize their contact with each other, forming a 💡compact ball of cells held together by tight junctions.
This process also 💡segregates inner cells, which communicate extensively by gap junctions, from outer cells.
Compaction
The two-cell stage is reached approximately __ after fertilization
30 hours
The four-cell stage is reached at approximately __
40 hours
During the development of the zygote, blastomeres are surrounded by the (1)__, which disappears at the end of the (2)__.
(1) zona pellucida
(2) fourth day
It is a 💡sac like structure that formed when the morula is filled with fluid.
Blastocele
The 12- to 16-cell stage is reached at approximately __.
3 days
It is the 💡cells of the inner cell mass from the blastocyst.
Embryoblast
It is the 💡flatten cells of the outer cell mass that form the epithelial wall of the blastocyst.
Trophoblast
The late mórula stage is reached at approximately __.
4 days
They 💡mediate the uterine epithelium initial attachment of the blastocyst to the uterus.
L-selectin (trophoblast cells)
Carbohydrate receptors
Embryoblast + Trophoblast
Blastocysts
When the zona pellucida disappears this will begin.
Implantation of the blastocyst.
The wall of the uterus consists of three layers:
- Endometrium or mucosa lining the inside wall
- Myometrium, a thick layer of smooth muscle
- Perimetrium, the peritoneal covering lining the outside wall
These are carbohydrate-binding proteins involved in interactions between leukocytes and endothelial cells that allow leukocyte “capture” from flowing blood.
Selectins
Integrin receptors for laminin promote (1)__, whereas those for fibronectin stimulate (2)__.
(1) attachment
(2) migration
This menstrual cycle phase 💡begins at the end of the menstrual phase, is under the influence of 💡estrogen, and 💡parallels growth of the ovarían follicles.
Begins approximately 2-3 days after ovulation
Proliferative Phase
This menstrual cycle phase begins approximately 2 to 3 days after ovulation in response to 💡progesterone produced by the corpus luteum.
Secretory Phase
This marks the 💡beginning of the menstrual phase.
Shedding of the endometrium
Later in gestation, the __ assumes the role of hormone production, and the corpus luteum degenerates.
Contains 💡trophoblastic cells that penetrate between the epithelial cells of the uterine mucosa (6th day)
Placenta
From puberty (11 to 13 years) until menopause (45 to 50 years), the endometrium undergoes changes in a cycle of approximately __ under hormonal control by the ovarles.
28 days
During this menstrual cycle, the uterine endometrium passes through three stages:
- Follicular or proliferative phase
- Secretory or progestational phase
- Menstrual phase
💡Blood escapes from superficial arteries, and small pieces of stroma and glands break away.
MENSTRUAL PHASE
The 💡only part of the endometrium that is 💡retained following 3 or 4 days of menstruation.
Basal Layer
They are part of the endometrium that is 💡expelled from the uterus following 3 or 4 days of menstruation.
Compact Layer
Spongy Layer
It is the own arteries of the basal layer that functions as the 💡regenerative layer in the rebuilding of glands and arteries in the proliferative phase
Basal Arteries
Events during the first week of human development.
- Oocyte immediately after ovulation
- Fertilization, approximately 12 to 24 hours after ovulation
- Stage of the male and female pronuclei
- Spindle of the first mitotic división
- Two-cell stage (approximately 30 hours of age];
- Morula containing 12 to 16 blastomeres (approximately 3 days of age]
- Advanced mórula stage reaching the uterine lumen (approximately 4 days of age)
- Early blastocyst stage (approximately 4.5 days of age; the zona pellucida has disappeared]
- Early phase of implantation (blastocyst approximately 6 days of age).
At the time of implantation, the mucosa of the uterus is in the __.
secretory phase
Contraceptive Methods
Barrier Methods
Hormonal Methods
Intrauterine Device (IUD)
Sterilization
Barrier Methods
Male and Female Condoms
A type of IUD that releases 💡progestin that causes thickening of cervical mucus to prevent sperm from entering the uterus.
Hormonal IUD
A type of IUD that releases 💡copper into the uterus that prevents fertilization or inhibits attachment of the fertilized egg to the uterine wall.
Copper IUD
These contraceptive pills are used as birth control measures that may prevent pregnancy if taken 💡120 hours after sexual intercourse.
Emergency contraceptive pills (ECPs)
A sterilization method for men which 💡prevents the release of sperm by 💡blocking the ductus deferens, the tube that transports sperm from the testes to the penis.
Vasectomy
The sterilization method for women which the 💡uterine tubes are blocked or ligated.
Tubal sterilization
A drug given early in the menstrual cycle that is used to 💡increase FSH concentrations to stimulate ovulation.
Clomiphene citrate (Clomid)
These pluripotent cells are 💡derived from the inner cell mass of the embryo.
Embryonic stem cells (ES cells)
A process of 💡obtaining embryonic cell from embryos after IVF
Reproductive Cloning
It is a technique that 💡take nuclei from adult cells (e.g., skin) and introduce them into enucleated oocytes. Oocytes are stimulated to differentiate into blastocysts, and ES cells are harvested.
Therapeutic cloning or Somatic Nuclear Transfer.
Hormonal Methods
Birth Control Pills
Skin Patch
Vaginal Ring
Injection
2 types of Birth Control Pills:
- Combination of estrogen and progestin
2. Progestin alone
