[Module 3] Stages of Fetal Development Flashcards
What are the 3 stages of fetal development?
Preembryonic
Embryonic
Fetal
the stage of first 2 weeks, beginning with fertilization
Preembryonic stage
stafe of fetal development from weeks 3 through 8
Embryonic
Period of fetal development from week 8 through birth
Fetal
Refers from ovulation to fertilization
Ovum
Terms used that refers from fertilization to implantation
Zygote
Refers to the period of implantation to 5- 8 weeks
Embryo
Refers to the period from 5-8 weeks until term
Fetus
It refers to the developing embryo & placental structures throughout pregnancy
Conceptus
It is the earliest age at which fetuses survive if born is generally accepted as 24 weeks or at the point a fetus weighs more than 500-600 g
Age of Viability
physiologic removal of acrosome(cap) of the sperm
capacitation
final process that sperm must undergo to be ready for fertilization
capacitation
reaction that occurs in the acrosome of the sperm as it approaches the egg
Acrosome reaction
proteolytic enzyme released by the spermatozoa
Hyaluronidase
This enzyme acts to dissolve layers of cells protecting the ovum
Hyaluronidase
these are cells that encircle the zona pellucida
corona radiata
This is the protective covering of the ovum
Zona Pellicuda
refers to the action that the ovum becomes impenetrable to other sperm
zona reaction
fertilization is never a certain occurrence because it depends on at least three separate factors, what are these factors?
-Equal maturation of both sperm and ovum
-Ability of the sperm to reach the ovum
-Ability of the sperm to penetrate the zona pellucida and cell membrane and achieve fertilization
what is the lifespan of the ovum?
24-48 hours
lifespan of the sperm is what?
48-72 hours
Pregnant women state that she waddles when she walks. What causes this?
Relaxation of the Pelvic Joints