Early Embryogenesis and Maternal Recognition of Pregnancy Flashcards
What is the parental imprinting?
The perferable expression of genes from either the male or female parent.
What parent does placentation come from?
Male.
What parent does embryo development come from?
Female.
What occurs when two egg pronuclei are placed in the same egg?
Near normal embryo, small placenta.
What occurs when two sperm pronuclei are placed in the same egg?
Stunted embryo, near normal placenta.
What are pleuripotent cells?
Cells that will either become the embryo or the placenta.
What are multipotent cells?
Cells that are set to become a specific tissue type.
What are totipotent cells?
Cells that can become a completely new tissue type or individual.
*Exist until the morula.
What is the morula?
An embryo with 16 or more cells.
What is blastulation?
When a morula becomes a blastocyst.
What is a blastocyst?
A structure where an inner cell mass/embryoblast, blastocele, and trophoblasts can be seen.
What does the inner cell mass/embryoblast become?
The fetus.
What does the trophectoderm become?
The placenta.
What are the stages of development (in order) from ootid to hatched blastocyst?
- Ootid.
- Zygote.
- 2-cell embryo.*
- Morula.
- Early blastocyst.
- Hatching blastocyst.
- Hatched blastocyst.
*This stage is normally followed by a 4-cell and 8-cell embryo step.
An increased level of what macromolecule makes the embryo appear darker?
Lipids.
How many days does it take from ovulation until the embryo reaches the uterus?
2-6.5 days.
What are the three stages of conceptus growth (sheep, pigs, cattle)?
- Spherical.
- Tubular.
- Filamentous
*Then uterus or STFU.
What is unique about mare conceptus growth?
The conceptus stays spherical for an extended period of time.
In which uterine horn does the elongating blastocyst attach in ruminants?
The horn that has the ovary with the CL.
What is intrauterine migration?
When the embryos enter the uterus and migrate between the two horns until a certain point when they then fix themselves to a uterine horn.
What animal embryos undergo intrauterine migration?
Pig embryos.
On what day does intrauterine migration end in pigs?
Day 12.
What is transuterine migration?
When the embryo moves throughout the uterus until a certain point when it then fixes itself to a uterine horn.
What animal embryos undergo transuterine migration?
Horse embryos.
When does transuterine migration begin and end in horses?
Begins on day 10 and ends on day 15-16.
What does the bovine conceptus secrete?
Bovine interferon.
What does the ovine conceptus secrete?
Ovine interferon.
What is the maternal response to the conceptus’s secretion in the bovines and ovines?
- Antiluteolytic.
- Inhibits oxytocin receptor synthesis.
- Inhibits PGF2a synthesis.
What are the critical days for bovines?
Day 16 to 17.
What are the critical days for ovines?
Day 12-13.
What does the swine conceptus secrete?
E2.
What is the maternal response to the conceptus secretion in swine?
- Antiluteolytic.
- Redirect PGF2a to the lumen of the uterine horn.
*Requires two embryos per horn.
What does the equine conceptus secrete?
The scientific community is unsure.
*Triggered by touch.
What is the maternal response to the conceptus’s secretion in the equines?
- Antiluteolytic.
- PGF2a is not being released into the vasculature.
What are the critical days for equines?
Day 10-12.
What are the critical days in swine?
Day 11-12.
What does human conceptus release?
hCG.
What is the maternal response in humans?
Luteotrophic.
What are the critical days for humans?
Day 8-12.
