• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/43

Click to flip

43 Cards in this Set

  • Front
  • Back
What is sperm capacitation?
Functional changes of the sperm to allow penetration of the zone pellucida.
What is the acrosomal reaction?
Release of proteolytic enzymes within the acrosomal membrane of the sperm that permit attachment to the zona pellucida (ZP3 receptors).
What are the 3 proteolytic enzymes released in the acrosomoal reaction?
1) hyaluronidase
2) acrosin
3) neuroamidase
How is multiple sperm attachment to a single egg (polyspermy) prevented?
The first penetrating spermatozoa triggers an increase of Ca, which causes degranulation of the plasma membrane vesicles, releasing enzymes that harden the zona pellucida.
What else occurs as a result of an increase in Ca?
The second meiotic division is allowed to continue, fusion with sperm produces zygote formation.
How long does it take for sperm to appear in the ampulla, post-coitus?
5-6 minutes.
How many viable sperm make it to the oviduct?
0.1%
How long can a sperm survive, retaining its ability to fertilize?
24-48 hrs.
What time in the woman's cycle is optimal for fertilization?
Within 24 hrs. of ovulation.
How does estrogen affect sperm transport?
The female tract becomes watery and more viable for sperm to survive and travel.
How does cGMP affect sperm transport?
Increases its velocity and directionality.
How does the basic environment of the vagina affect sperm transport?
Increases sperm transport.
How does the oviduct/fallopian tube aid in sperm transport?
Increase ciliary movement, peristaltic contractions, and fluid flow push sperm toward the ampulla.
What draws the oocyte out of the ovary?
Fimbriae.
What feature of the ampulla increases probability of fertilization?
Contraction and churning of the ampulla wall.
How long does the morula/blastocyst require to get through the oviduct?
About 3 days.
What determines the timing and arrival of the morula/blastocyst to the uterine cavity?
Progesterone and estrogen balance.
How does estrogen affect morula/blastocyst transport?
Stimulates constriction of the isthmus to prevent uterine entry, probably to allow endometrium more time to develop.
How does progesterone affect morula/blastocyst transport?
Stimulates myometrium relaxation and facilitates transport to the uterus.
What are the 3 processes of implantation to the endometrium?
1) Adhesion
2) Penetration
3) Invasion
What is the first step of adhesion?
Zone pellucida dissolves.
How does progesterone affect adhesion?
I don't know. Find this out.
What are integrins?
Binding molecules that connect endometrial cells to each other, and blastocyst cells to each other.
What cytokine will be released during adhesion and what is its function?
IL-1.
Increase integrins in the endometrial cells.
What is osteopontin?
It is a molecule that binds to integrins of endometrium and to those of the blastocyst.
What is the trophoblast?
A region that extends from the blastocyst and latches on to endometrial cells via laminin and fibronectin, both of which induce adhesion.
What is the role of decidual cells?
It grows as a source of nutrients, a mechanical and immune barrier, and as an endocrine gland.
(I think this will eventually aid in penetration.)
How does invasion progress?
Trophoblasts from fetus and decidual cells from mother must coordinate to cause invasion.
What is the role of IGF-2 and IGF-BP in invasion?
They stimulate invasion.
What are syncytiotrophoblasts and what do they do?
Placental cells that are
analagous to the pituitary -
responsible for most hormone production.
What are cytotrophoblasts and what do they do?
Placental cells that are an analog to the hypothalamus in that it produces stimulatory and inhibitory control over the syncytiotrophoblast.
What is the primary role of oral contraceptives?
Prevent ovulation.
How do oral contraceptives affect the pituitary and hypothalamus?
Suppress LH surge, thus preventing ovulation. Supress basal gonadotropin levels. Suppress FSH preventing follicular growth.
How do oral contraceptives affect the fallopian tube?
Decreases its motility.
How do oral contraceptives affect the endometrium?
Cause glandular atrophy, which prevents implantation.
How do oral contraceptives affect the cervical mucus?
Thickens it, inhibiting sperm motility and transport.
What are the 3 types of oral contraceptives and how do they work?
1) Fixed combination - constant estrogen and progestagen throughout the cycle.
2) Biphasic and triphasic - constant estrogen, variable progestagen.
3) Progestagen-only
What are the risks of oral contraception?
Hypertension, myocardial infarction, stroke - contraindicated in heavy smokers over 35, and history of estrogen-dependent breast carcinomas.
What are 4 benefits of oral contraception?
1) Treatment of excessive bleeding
2) Aid in dysmenorrhea
3) Hormone replacement for post-menopausal women
4) Protect against pelvic inflammatory disease.
What are 4 ways to prevent contact of germ cells to avoid fertilization?
1) Abstinence
2) Coitus interruptus (pulling out)
3) Physical barriers: condoms, diaphragms, cervical caps (together with spermicides).
4) Periodic abstinence around the time of ovulation.
What are 3 ways to prevent implantation of the fertilized egg?
1) High doses of estrogen
2) Progesterone receptor antagonist (RU486)
3) IUD provokes sterile inflammation of the endometrium, preventing implantation.
What are 2 methods of abortion?
1) Prostaglandin administration will increase uterine contraction and terminate pregnancy.
2) Surgical removal - dilatation and curettage.
What are the 3 functions of the placenta?
1) Transport of nutrients
2) Removal of waste products
3) Endocrine hormone release - cytotrophoblasts and syncytiotrophoblasts