ATI RN
Human Reproductive System pdf NCERT Questions
Question 1 of 5
A scientist studying developmental physiology performs an experiment in which a substance is given to pregnant rats that give birth to pups that have XY chromosomes but female genital organs. What was the substance given to the rats?
Correct Answer: A
Rationale: The correct answer is A: An antibody that blocked the effect of human chorionic gonadotropin in the embryo and fetus. Human chorionic gonadotropin (hCG) is crucial for male sexual differentiation. Blocking its effects would lead to the development of female genital organs in pups with XY chromosomes. Estrogen-like compounds (B) and follicle-stimulating hormone (C) are not directly involved in male sexual differentiation. Testosterone (D) is responsible for male sexual development, so giving testosterone would not result in female genital organs in XY pups.
Question 2 of 5
At what point in life does a female begin her monthly ovarian cycle?
Correct Answer: B
Rationale: The correct answer is B: At puberty. The monthly ovarian cycle, also known as the menstrual cycle, begins at puberty when a female's body matures and starts ovulating. This is typically around the age of 11-14. At birth (A), females already have all their eggs but do not start ovulating until puberty. Middle age (C) refers to the period around 40-65, which is not when the cycle begins. Menopause (D) is the cessation of the menstrual cycle, marking the end of reproductive years, typically around the age of 45-55.
Question 3 of 5
What excess cellular component do spermatids shed to become sperm during spermiogenesis?
Correct Answer: B
Rationale: During spermiogenesis, spermatids shed excess cytoplasm to become mature sperm. This process helps streamline the sperm structure for efficient motility and fertilization. DNA (choice A) is essential for sperm function and remains within the sperm. The flagellum (choice C) is actually a necessary structure for sperm motility. Mitochondria (choice D) play a crucial role in providing energy for sperm movement. Shedding excess cytoplasm ensures that the mature sperm is streamlined and optimized for its specific functions.
Question 4 of 5
Which of the following is responsible for secondary sex characteristics in females?
Correct Answer: A
Rationale: Estrogens are responsible for secondary sex characteristics in females as they promote breast development, regulate the menstrual cycle, and contribute to the distribution of body fat. Progesterone mainly prepares the uterus for pregnancy. Follicle-stimulating hormone (FSH) plays a role in the development of ovarian follicles and the maturation of eggs but does not directly influence female secondary sex characteristics.
Question 5 of 5
This tiny gland produces a secretion that is similar to a large lysosome and that cleanses the male urethra of assists penetration of the egg is called traces of acidic urine prior to the ________.
Correct Answer: D
Rationale: The correct answer is D: bulbo-urethral gland. This gland produces a clear secretion that neutralizes traces of acidic urine, lubricates the urethra, and assists in sperm motility. The other choices are incorrect because: A: Flagellum is a structure on sperm cells for propulsion. B: Prostate produces seminal fluid but does not cleanse the urethra. C: Midpiece is a part of the sperm cell that contains mitochondria for energy production, not a gland.