 |
| 1 | |
Embryogenesis refers to the same period of time as |
| | A) | the prenatal period |
| | B) | the gestation period |
| | C) | pregnancy |
| | D) | all of the above |
|
|
|
| 2 | |
All of the following accurately describe aspects of fertilization except |
| | A) | sperm cells first undergo capacitation in the female reproductive tract |
| | B) | egg cells must be fully mature before they can be ovulated or fertilized |
| | C) | to remain viable, an egg must be fertilized within 24 hours of ovulation |
| | D) | sperm cells typically encounter the egg in the ampulla of the uterine tube |
|
|
|
| 3 | |
Which stage of meiosis lasts much longer in females than in males? |
| | A) | Prophase I |
| | B) | Anaphase I |
| | C) | Metaphase II |
| | D) | Telophase II |
|
|
|
| 4 | |
All of the following occur during spermiogenesis except |
| | A) | spermatids lose much of their cytoplasm and grow a flagellum |
| | B) | mature sperm cells, or spermatozoa, are formed |
| | C) | sperm become completely ready to fertilize an egg cell |
| | D) | neither b nor c occurs during spermiogenesis |
|
|
|
| 5 | |
Under normal conditions, how many of the four spermatozoa produced from each spermatocyte contain a Y chromosome? |
| | A) | two |
| | B) | four |
| | C) | one |
| | D) | the number varies randomly |
|
|
|
| 6 | |
Which of the following must occur between the first phase of fertilization and zygote formation? |
| | A) | the sperm undergoes capacitation |
| | B) | the egg completes meiosis II |
| | C) | the first polar body forms |
| | D) | all of the above |
|
|
|
| 7 | |
Crossing over is the process by which |
| | A) | homologous chromosomes trade parts during meiosis |
| | B) | genes can be shuffled even before fertilization occurs |
| | C) | one chromosome can combine genes from both parents |
| | D) | all of the above |
|
|
|
| 8 | |
Which one of the following phrases does not accurately describe the blastodisc? |
| | A) | forms during the second week of development |
| | B) | is composed of two layers of cuboidal germ cells |
| | C) | contains a hypoblast layer and an epiblast layer |
| | D) | gives rise to the embryo, amnion, and yolk sac |
|
|
|
| 9 | |
The second week of development can be characterized as the "period of twos" because |
| | A) | a two-layered germinal disc forms, and from it, two extraembryonic cavities |
| | B) | the placenta begins to develop from two components that merge |
| | C) | both of the above |
| | D) | neither a nor b is true |
|
|
|
| 10 | |
The placenta provides services for the fetus that will eventually be performed by which of the following organ systems? |
| | A) | digestive |
| | B) | respiratory |
| | C) | urinary |
| | D) | all of the above |
|
|
|
| 11 | |
Although the bilaminar germinal disc contains two layers of cells, only the ____________ gives rise to the three layers of the trilaminar embryo. |
| | A) | epiblast |
| | B) | hypoblast |
| | C) | cytotrophoblast |
| | D) | syncytiotrophoblast |
|
|
|
| 12 | |
The pre-embryo arrives in the uterine cavity as a ____________, but it is a ____________ by the time it begins implantation. |
| | A) | zygote; morula |
| | B) | morula; blastocyst |
| | C) | morula; gastrula |
| | D) | blastocyst; gastrula |
|
|
|
| 13 | |
In the blastocyst, the fluid-filled chamber that separates the bilaminar germinal disc from the trophoblast is the |
| | A) | blastocoel |
| | B) | amniotic cavity |
| | C) | chorionic cavity |
| | D) | yolk sac |
|
|
|
| 14 | |
The invagination or migration of cells from the epiblast into the space between it and the hypoblast marks the beginning of |
| | A) | cleavage |
| | B) | organogenesis |
| | C) | gastrulation |
| | D) | neurulation |
|
|
|
| 15 | |
All three primary germ layers develop from the same cellular layer in the blastodisc as which extraembryonic membrane? |
| | A) | chorion |
| | B) | yolk sac |
| | C) | trophoblast |
| | D) | amnion |
|
|
|
| 16 | |
Although neurulation primarily involves changes in ectoderm, it could not occur without inductive interaction between |
| | A) | mesoderm and endoderm |
| | B) | endoderm and ectoderm |
| | C) | ectoderm and mesoderm |
| | D) | both a and b |
|
|
|
| 17 | |
The umbilical cord comprises which of the following structures? |
| | A) | connecting stalk, umbilical vessels, and allantois |
| | B) | chorionic villi and maternal blood vessels |
| | C) | stratum basalis and stratum functionalis |
| | D) | all of the above |
|
|
|
| 18 | |
Fetal metabolic wastes are eliminated by transfer to the |
| | A) | amniotic fluid |
| | B) | maternal blood |
| | C) | yolk sac |
| | D) | all of the above |
|
|
|
| 19 | |
Human chorionic gonadotropin (hCG) from the syncytiotrophoblast serves to |
| | A) | prevent menstruation that would end the pregnancy |
| | B) | allow early detection of pregnancy in modern diagnostic tests |
| | C) | both a and b |
| | D) | neither a nor b |
|
|
|
| 20 | |
Which of the following would be the most likely consequence of a genetic defect that prevented the placenta from producing hormones? |
| | A) | spontaneous abortion within the first week of pregnancy |
| | B) | loss of the fetus because of inadequate oxygen supply |
| | C) | severely underweight birth after a normal gestation period |
| | D) | miscarriage as soon as the corpus luteum ceases to function |
|
|
|
| 21 | |
Amniocentesis is most often performed during which month of pregnancy? |
| | A) | third |
| | B) | fourth |
| | C) | fifth |
| | D) | sixth |
|
|
|
| 22 | |
Fetal alcohol syndrome and congenital syphilis share what etiological aspect? |
| | A) | both result from alcohol consumption by the mother during pregnancy |
| | B) | both are exacerbated by smoking or drug use during pregnancy |
| | C) | both are acquired from the mother across the placental barrier |
| | D) | all of the above |
|
|
|
| 23 | |
Teratogens would be most likely to cause which of the following types of congenital anomalies? |
| | A) | malformations |
| | B) | disruptions |
| | C) | deformations |
| | D) | all of the above |
|
|
|
| 24 | |
Cellular differentiation causes a decrease in |
| | A) | specialization |
| | B) | totipotency |
| | C) | growth |
| | D) | development |
|
|
|
| 25 | |
What must actually rupture when the "water breaks" during labor? |
| | A) | chorion |
| | B) | amnion |
| | C) | endometrium |
| | D) | all of the above |
|
|
.