An Sci 434 Final Flashcards
The formation of the blastocyst involves the pump of Na+ and H2O into the center of the embryo.
T
Hatching of the bovine blastocyst occurs on days 9-11.
T
While the cow, sheep, and pig conceptuses go through spherical, tubular, and filamentous stages, the equine conceptus remains spherical.
T
Transmigration of the embryo from one uterine horn to the other occurs in the pig and horse but not in the sheep or cow.
T
During gastrulation, the endoderm lines the inside of the blastocoele cavity, forming the yolk sac portion of the placenta.
T
Which of the following tissues are derived from the ectoderm?
Skin and Central Nervous System
Which of the following tissues are derived from the mesoderm?
Reproductive Tract
Which of the following tissues are derived from the endoderm?
Lungs
Which placental membrane functions as the source of primordial germ cells and red blood cells?
Yolk Sac
Which placental membrane functions to bring the blood vessels to the surface of the placenta?
Allantois
Which placental membrane functions as a shock absorber and is non-vascular?
Amnion
Which placental membrane attaches to the mother?
Chorion
The signal for maternal recognition of pregnancy in the cow is the production of the interferon tau by the early conceptus
T
The signal for maternal recognition of pregnancy in the pig is production of porcine chorionic gonadotropin.
F
There is no maternal recognition of pregnancy event in the dog and cat. The CL lasts the same period of time both in the non-pregnant and pregnant animal.
T
Which of the following have a superficial type of implantation?
Cow, Sheep, Sow
Which of the following have an interstitial type of implantation?
Human
Which of the following have a cotyledonary placenta?
Cow
Which of the following have a zonary placenta?
Dog
The binuclear giant cells of the bovine placenta produce which of the following?
Lactogen, Pregnancy Specific hormone B
Maternal and fetal blood is separated by 3 tissue layers in a hemoendothelial placenta.
F
A lueteotrophic compound is produced by the embryo that is responsible for maternal recognition of pregnancy in the.
Human
A graduate student is dissecting a pregnant dog uterus. He finds multiple tissue layers separating the maternal and fetal blood flow of this endothelial-chorial placenta. Which of the following layers is ABSENT in this placenta?
Maternal Epithelium
Examples of the placental function of exchange include which of the following?
Urea, Oxygen, and Glucose
Examples of the placental function of chemical protection include which of the following?
Immunosuppressants, filtering of environmental toxins, protection against maternal defenses
One physical protection function of the placenta is acting as a shock absorber for the fetus.
T
One endocrine function of the placenta is the transient production by the placenta of estrogen, progesterone, and placental lactogen.
T
The fetal age can be estimated by which of the following?
Femur and Crown-Rump Lengths
The uterus changes size during pregnancy in which of the following ways?
Hypertrophy, Hyperplasia, Stretching
Fetal circulation is different from adult circulation due to the presence of which additional structures?
Foramen Ovale, Ductus Venosus, Ductus arteriosus
A woman without ovaries can maintain a pregnancy if given progesterone daily for the first 90 days of pregnancy.
T
A mare who continually aborts before day 60 of pregnancy can be given progesterone up through day 120 of gestation to help maintain a pregnancy.
T
What is the length of gestation in the cow?
280 Days
Increased litter size in pigs will result in individual baby pigs in the litter being smaller in size and/or weight.
T
Which of the following are examples of environmental effects on fetal size?
Parity and Feed Availability to the Mother
Endometrial cups are important during pregnancy in the mare because they make which of the following hormones?
ECG
A cow was exposed to a pesticide know to cause birth defects in humans. The exposure occurred at 10 – 14 days into gestation. The cow was sent to slaughter 2 months latter and the fetus was recovered and found to not have kidneys, reproductive tract or urinary tracts. The likely effect of the pesticide was to interfere with formation of the.
Mesoderm
You are making a presentation to a high school class on pregnancy and gestation. One the students asks you what is the most likely cause for a pregnancy to fail. You respond that, in your opinion, it is failure of imprinting. Your answer indicates that you think that failure of pregnancy occurs most during which stage?
Embryo Development
Increased prenatal losses could be due to which of the following reasons?
Nutritional Stress, Endocrine Imbalances, Diseases of Reproductive tract
What is the role of estrogen during parturition?
To induce uterine myometrial gap junctions, To induce uterine endometrial oxytocin receptors, To induce relaxin release from the CL.
What is the role of cortisol during parturition?
To induce formation of surfactant in the fetal lung, to induce glycogen formation in the fetal liver, to cause the fetal thyroid to release its hormones and increase fetal metabolism, to stimulate the conversion of progesterone to estradiol in the placentome
In response to fetal stress at the end of gestation, which of the following is the first to occur?
CRH release from the hypothalamus