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.

Correct Answer: D

Rationale: The correct answer is D: an embryo. From fertilization to week 8 of the proliferative phase of uterine pregnancy, the conceptus is referred to as an embryo. This is because during this period, the fertilized egg undergoes rapid cell division and differentiation, leading to the formation of distinct embryonic structures and the beginning of organ development. The term "fetus" is used after the embryonic stage, typically from week 9 onwards. Choices A and C, estrogens and progesterones respectively, are hormones involved in regulating the menstrual cycle and maintaining pregnancy but are not terms used to describe the developing conceptus itself during this specific timeframe.

Correct Answer: C

Rationale: The correct answer is C because a female actually ovulates only about 400-500 oocytes during her lifetime, not 2,000 to 4,000. This is due to the process of follicular atresia where many oocytes are lost before ovulation. Choice A is correct as females have a finite number of oocytes at birth. Choice B is correct as oogonia differentiate into primary oocytes during fetal development. Choice D is incorrect as typically only one oocyte is fertilized during each menstrual cycle.

Correct Answer: A

Rationale: The correct answer is A because ejaculation is primarily controlled by the sympathetic nervous system, not the para-sympathetic system. The sympathetic nervous system triggers the contraction of smooth muscles to allow for ejaculation. Choice B is incorrect because ejaculation is not a result of summation of synaptic potentials, but rather a coordinated response. Choice C is incorrect because semen is expelled by rhythmic contractions of the pelvic floor muscles, not the urethral smooth muscle. Choice D is incorrect because ejaculation involves the discharge of sperm, seminal vesicle, prostatic secretions, and other fluids from the reproductive system.

Correct Answer: C

Rationale: Rationale: C is correct because Leydig cells in the testes secrete testosterone, which is essential for stimulating spermatogenesis in the Sertoli cells. Testosterone plays a crucial role in the development and maturation of sperm. A is incorrect because follicle stimulating hormone is secreted by the pituitary gland, not the hypothalamus. B is incorrect because luteinizing hormone is secreted by the pituitary gland, not the hypothalamus. D is incorrect because Leydig cells primarily secrete testosterone, not inhibin.