Reproductive System Exam Quizlet

Correct Answer: A

Rationale: The correct answer is A: 250,000. At birth, there are approximately 250,000 primordial follicles in the cortex of each ovary. These primordial follicles represent the reserve of oocytes that a female will have throughout her reproductive life. Choice B, 200,000, is incorrect as the number is higher. Choices C and D, 150,000 and 100,000 respectively, are also incorrect as they underestimate the actual number of primordial follicles present at birth.

Correct Answer: D

Rationale: The correct answer is D. During the menstrual phase of the menstrual cycle, the endometrium is shed up to the basal layer. This shedding occurs as a result of decreased levels of estrogen and progesterone, leading to the breakdown and subsequent shedding of the endometrial lining. Choice A, ovulation, is incorrect as ovulation is the release of an egg from the ovary, which occurs during the mid-cycle. Choice B, regenerative, is incorrect as it does not specifically refer to the phase where the shedding of the endometrium occurs. Choice C, secretory, is incorrect as it refers to the phase where the endometrium thickens in preparation for possible implantation of a fertilized egg, not shedding.

Correct Answer: A

Rationale: The first menstrual period, known as menarche, typically occurs between the ages of 9 and 15 years. This marks the onset of puberty in females. Choices B, C, and D are incorrect because the first menstrual period does not occur as early as 2 years old, 1 year old, or as late as 18 to 20 years old.

Correct Answer: A

Rationale: The correct answer is A, Copper-T. Copper-T is an intrauterine device that releases copper ions, which suppress sperm motility and inhibit the implantation of the blastocyst. This method mainly works by preventing fertilization and, if fertilization occurs, by making the endometrium less receptive to implantation. Choices B, C, and D are incorrect. The diaphragm is a barrier method that prevents sperm from reaching the cervix; contraceptive pills mainly work by suppressing ovulation and altering cervical mucus to prevent sperm from reaching the egg; condoms are barrier methods that prevent sperm from entering the vagina.

Correct Answer: C

Rationale: There are two arteries in an umbilical cord. The umbilical cord contains two arteries and one vein. Artery carries blood away from the fetus, while the vein returns blood to the fetus. Therefore, choices A, B, and D are incorrect as they do not represent the correct number of arteries in an umbilical cord.