ANSC 333- Exam #4
Syngamy - ANS-fusion of male and female pronuclei
Zygote - ANS-single cell embryo
When does a zygote transition into an embryo? - ANS-After syngamy
Totipotent - ANS-can be anything (placenta or fetus)
Pluripotent - ANS-made a decision but is not yet fully differentiated
Cells in the middle of an embryo form - ANS-gap junctions
Cells on the outside on an embryo form - ANS-tight junctions
Compaction occurs within - ANS-the morula
Gap junctions mean the cell is part of - ANS-fetus
Tight junctions mean the cell is part of - ANS-placenta
Blastocoele - ANS-fluid filled cavity in blastocyst
Fluid accumulates inside the embryo after tight junctions form, Na transporters pump
water into the cell - ANS-How a blastocoele is formed
Blastocyst - ANS-embryo with distinct cavity
2 cell populations in embryo due to junctions: - ANS-Inner cell mass and trophoblast
Inner cell mass consists of - ANS-embryo body
Trophoblast consists of - ANS-chorion (placenta)
Hatching - ANS-Growth and fluid accumulation within blastocyst
Enzymes produced by trophoblastic cells
Contraction of blastocyst
Enzymes weaken zona pellucida and causes rupture
, When does embryo move from the uterus to the oviduct? - ANS-4-5 days of pregnancy
Ideal ET dates - ANS-Day 7 in cattle
Day 6 in sheep
Is early ET at day 4 possible? - ANS-Biologically yes, but more invasive die to embryo
being located in the oviduct instead of uterus
Is late ET at day 10 possible? - ANS-Biologically yes, embryo has not attached to uterus
but decreased pregnancy rate to hatching already
Higher risk of damage to embryo after hatching due to - ANS-loss of zona pellucida
Staging an embryo - ANS-Based on production stage
Grading an embryo - ANS-Based on percentage of live and viable cells
Initiate Implantation - ANS-physical attachment to uterus
In livestock, embryo attaches to - ANS-top of lumen
In primates, embryo attaches by - ANS-burrowing into endometrium
Signal for maternal recognition produced by - ANS-embryo
Extraembryonic membranes of preattachment embryo - ANS-Yolk sac
Chorion
Amnion
Allantois
Yolk sac - ANS-cavity develops from primitive endoderm, site of primitive germ cells that
migrate to gonads; regression as conceptus develops
Choroin - ANS-double membrane formed from trophoblast and mesoderm, eventually
forms complete sac around embryo
Amnion - ANS-fluid filled sac surrounding embryo that provides protection
Syngamy - ANS-fusion of male and female pronuclei
Zygote - ANS-single cell embryo
When does a zygote transition into an embryo? - ANS-After syngamy
Totipotent - ANS-can be anything (placenta or fetus)
Pluripotent - ANS-made a decision but is not yet fully differentiated
Cells in the middle of an embryo form - ANS-gap junctions
Cells on the outside on an embryo form - ANS-tight junctions
Compaction occurs within - ANS-the morula
Gap junctions mean the cell is part of - ANS-fetus
Tight junctions mean the cell is part of - ANS-placenta
Blastocoele - ANS-fluid filled cavity in blastocyst
Fluid accumulates inside the embryo after tight junctions form, Na transporters pump
water into the cell - ANS-How a blastocoele is formed
Blastocyst - ANS-embryo with distinct cavity
2 cell populations in embryo due to junctions: - ANS-Inner cell mass and trophoblast
Inner cell mass consists of - ANS-embryo body
Trophoblast consists of - ANS-chorion (placenta)
Hatching - ANS-Growth and fluid accumulation within blastocyst
Enzymes produced by trophoblastic cells
Contraction of blastocyst
Enzymes weaken zona pellucida and causes rupture
, When does embryo move from the uterus to the oviduct? - ANS-4-5 days of pregnancy
Ideal ET dates - ANS-Day 7 in cattle
Day 6 in sheep
Is early ET at day 4 possible? - ANS-Biologically yes, but more invasive die to embryo
being located in the oviduct instead of uterus
Is late ET at day 10 possible? - ANS-Biologically yes, embryo has not attached to uterus
but decreased pregnancy rate to hatching already
Higher risk of damage to embryo after hatching due to - ANS-loss of zona pellucida
Staging an embryo - ANS-Based on production stage
Grading an embryo - ANS-Based on percentage of live and viable cells
Initiate Implantation - ANS-physical attachment to uterus
In livestock, embryo attaches to - ANS-top of lumen
In primates, embryo attaches by - ANS-burrowing into endometrium
Signal for maternal recognition produced by - ANS-embryo
Extraembryonic membranes of preattachment embryo - ANS-Yolk sac
Chorion
Amnion
Allantois
Yolk sac - ANS-cavity develops from primitive endoderm, site of primitive germ cells that
migrate to gonads; regression as conceptus develops
Choroin - ANS-double membrane formed from trophoblast and mesoderm, eventually
forms complete sac around embryo
Amnion - ANS-fluid filled sac surrounding embryo that provides protection