Question 1

In a court case,a company was sued because a pregnant woman was exposed to chemical vapors one day and subsequently gave birth to an infant with a cleft lip/palate.The embryo was said to have had a menstrual age of 10 weeks at the time of exposure.What was the fertilization age of the embryo?

A)6 weeks
B)8 weeks
C)10 weeks
D)12 weeks
E)14 weeks

B

Accepted Answer

Menstrual age refers to the length of time since the woman's last menstrual period, while fertilization age is the time since conception. On average, ovulation occurs about two weeks after the start of a woman's menstrual cycle, and fertilization occurs shortly after. Therefore, subtracting two weeks from the 10 weeks of menstrual age gives a fertilization age of 8 weeks.

Question 2

A woman is told by her obstetrician that she is already 7 weeks pregnant.What is the fertilization age of her embryo?&#10;A)5 weeks&#10;B)6 weeks&#10;C)7 weeks&#10;D)8 weeks&#10;E)9 weeks

Accepted Answer

The fertilization age of an embryo is typically 2 weeks less than the gestational age, which is calculated from the first day of the last menstrual period. Since the woman is 7 weeks pregnant in gestational age, the fertilization age of the embryo would be 5 weeks.

Question 3

In a lawsuit,a woman contends that a congenital malformation of her child was due to her falling down on an icy sidewalk when she was in her eighth week of pregnancy (menstruation age).How many weeks after fertilization (fertilization age)was the embryo at the time of the fall?

A)4 weeks
B)6 weeks
C)8 weeks
D)10 weeks
E)12 weeks

B

Accepted Answer

Menstruation age is typically counted from the first day of a woman's last menstrual period, which occurs approximately 2 weeks before fertilization. So, if the woman was in her eighth week of pregnancy according to her menstrual age, she was actually 6 weeks pregnant according to fertilization age.

Question 4

What is a major function of protamines in spermatogenesis?&#10;A)They prevent autoimmune reactions against the spermatozoa.&#10;B)They are instrumental in the formation of the acrosome.&#10;C)They are associated with the membrane receptors for luteinizing hormone on the primary spermatocyte.&#10;D)They displace nuclear histones and allow compaction of the nuclear chromatin.&#10;E)They coat the maturing spermatozoa in the epididymis.

Accepted Answer

Protamines are small, positively charged proteins that replace the highly charged histones in the chromatin of spermatids during spermatogenesis. This replacement allows for efficient compaction of the genetic material into the small head of the mature spermatozoa, which is critical for motility and successful fertilization.

Question 5

Functional maturation of spermatozoa occurs in the _________.&#10;A)Epididymis&#10;B)Ductus deferens&#10;C)Prostate&#10;D)Seminal vesicle&#10;E)Upper vagina

Accepted Answer

The functional maturation of spermatozoa occurs in the epididymis, where they gain the ability to swim and fertilize an egg. The ductus deferens, prostate, seminal vesicle, and upper vagina do not play a role in the maturation of spermatozoa.

Question 6

Two systems-menstrual age and fertilization age-are used in signifying the age of embryos.To convert from menstrual age to fertilization age:&#10;A)Add 1 week&#10;B)Add 2 weeks&#10;C)Subtract 1 week&#10;D)Subtract 2 weeks

Accepted Answer

Menstrual age is typically calculated from the first day of the last menstrual period, which is about 2 weeks before fertilization occurs. Therefore, to convert menstrual age to fertilization age, you subtract 2 weeks.

Question 7

After it leaves a seminiferous tubule of the testes,a spermatozoon that fertilizes an ovum spends the longest time in the ____________.&#10;A)Epididymis&#10;B)Ductus deferens&#10;C)Seminal vesicle&#10;D)Cervical crypt&#10;E)Uterine tube

Accepted Answer

After leaving a seminiferous tubule, a spermatozoon enters the epididymis where it matures and gains motility. This process takes approximately 20 days, which is the longest time the sperm spends in any structure before ejaculation. The ductus deferens carries the sperm from the epididymis into the ejaculatory duct and ultimately the urethra. The seminal vesicle and prostate gland secrete fluids that make up semen, but the sperm only briefly pass through these structures. The cervical crypt and uterine tube are part of the female reproductive system and not involved in the maturation or transport of sperm.

Question 8

An alkaline fluid secreted by the ________ helps to raise the pH of the upper vagina after insemination.&#10;A)Testes&#10;B)Ovaries&#10;C)Prostate&#10;D)Seminal vesicles&#10;E)None of the above

Accepted Answer

The alkaline fluid is secreted by the seminal vesicles, which helps to neutralize the acidic environment of the vagina and allow for survival of the sperm. None of the other choices mentioned secretes an alkaline fluid.

Question 9

The first meiotic block in the human female gamete occurs in the ____________.&#10;A)Zygotene stage&#10;B)Diplotene stage&#10;C)Diakinesis stage&#10;D)Metaphase I stage&#10;E)Metaphase II stage

Accepted Answer

The answer of The first meiotic block in the human...

Question 10

As spermatozoa leave the testes and are joined by fluids from the prostate and seminal vesicles,they become motile because seminal fluid contains an external energy source.What is that energy source?&#10;A)Glucose&#10;B)Glycogen&#10;C)Ca++&#10;D)Fructose&#10;E)K+

Accepted Answer

Seminal fluid contains high levels of fructose, which serves as an energy source for spermatozoa. This allows them to swim and move towards the egg for fertilization. The other options mentioned (glucose, glycogen, Ca⁺⁺, and K⁺) are not present in high enough concentrations in seminal fluid to serve as a significant energy source for spermatozoa.

Deck 1: Getting Ready for Pregnancy