ANSC 534 EXAM 4 STUDY GUIDE (LATEST UPDATE) REAL
QUESTIONS AND VERIFIED ANSWERS |100% CORRECT |
ALREADY GRADED A
Name and describe the different types of implantation. Ans✓✓✓1.
Centric implantation
-long preattachment period
-blastocyst grows large and extensive extraembryonic membranes form
-noninvasive
-domestic animals
2. eccentric implantation
-blastocyst implants very soon
-membranes form after implantation
-invasive
-mice, rats, and hamsters
3. interstitial implantation
-blastocyst implants very soon
- membranes form after implantation
-most invasive
-primates, guinea pigs
What is gastrulation? How does it begin? Ans✓✓✓the formation of the
germ layers that begins with the formation of the bilaminar disc
,What are the components of the bilaminar disc? Ans✓✓✓the epiblast
and hypoblast
Name the cavity that is surrounded by cells of the epiblast in the human
embryo? Ans✓✓✓the amniotic cavity
What cells form the yolk sac? Ans✓✓✓hypoblast cells
What membranes fuse to form the chorion? Ans✓✓✓the mesoderm
fuses with the trophectoderm to form the chorion
What components of the embryo fuse to form the allantochorion?
Ans✓✓✓the allantois and chorion fuse forming the allantochorion
Name the extraembryonic membranes of the embryo. Describe briefly
theirfunctions. Ans✓✓✓1. yolk sac wall
-source of nutrients
2. amnion
-innermost layer
-its fluid suspends the embryo
3. allantois
-waste products
-oxygen support
, 4. chorion
-outermost layer
-protection
-attach to the uterus
Name the steps of implantation in sheep Ans✓✓✓1. Hatching
2. precontact and orientation
3. apposition
4. adhesion
5. endometrial invasion
Describe MUC-1. What is its function? What happens to it
duringimplantation? Ans✓✓✓-large transmembrane mucin glycoprotein
-controls accessibility of surface integrins to their ligands
-implantation cascade is initiated after downregulation of MUC1
(coincides with the loss of PR from uterine epithelium)
Describe the uterine gland knockout (UGKO) ewe. How was it created,
whatwas it used for, what were the findings? Ans✓✓✓-produced by
administration of non-metabolizable progestin to ewes from birth to at
least day 56
-no endometrial glands in the endometrium
-no adhesion proteins of endometrial origin
-exhibit early pregnancy loss
QUESTIONS AND VERIFIED ANSWERS |100% CORRECT |
ALREADY GRADED A
Name and describe the different types of implantation. Ans✓✓✓1.
Centric implantation
-long preattachment period
-blastocyst grows large and extensive extraembryonic membranes form
-noninvasive
-domestic animals
2. eccentric implantation
-blastocyst implants very soon
-membranes form after implantation
-invasive
-mice, rats, and hamsters
3. interstitial implantation
-blastocyst implants very soon
- membranes form after implantation
-most invasive
-primates, guinea pigs
What is gastrulation? How does it begin? Ans✓✓✓the formation of the
germ layers that begins with the formation of the bilaminar disc
,What are the components of the bilaminar disc? Ans✓✓✓the epiblast
and hypoblast
Name the cavity that is surrounded by cells of the epiblast in the human
embryo? Ans✓✓✓the amniotic cavity
What cells form the yolk sac? Ans✓✓✓hypoblast cells
What membranes fuse to form the chorion? Ans✓✓✓the mesoderm
fuses with the trophectoderm to form the chorion
What components of the embryo fuse to form the allantochorion?
Ans✓✓✓the allantois and chorion fuse forming the allantochorion
Name the extraembryonic membranes of the embryo. Describe briefly
theirfunctions. Ans✓✓✓1. yolk sac wall
-source of nutrients
2. amnion
-innermost layer
-its fluid suspends the embryo
3. allantois
-waste products
-oxygen support
, 4. chorion
-outermost layer
-protection
-attach to the uterus
Name the steps of implantation in sheep Ans✓✓✓1. Hatching
2. precontact and orientation
3. apposition
4. adhesion
5. endometrial invasion
Describe MUC-1. What is its function? What happens to it
duringimplantation? Ans✓✓✓-large transmembrane mucin glycoprotein
-controls accessibility of surface integrins to their ligands
-implantation cascade is initiated after downregulation of MUC1
(coincides with the loss of PR from uterine epithelium)
Describe the uterine gland knockout (UGKO) ewe. How was it created,
whatwas it used for, what were the findings? Ans✓✓✓-produced by
administration of non-metabolizable progestin to ewes from birth to at
least day 56
-no endometrial glands in the endometrium
-no adhesion proteins of endometrial origin
-exhibit early pregnancy loss
