The tiny female sex cell that unites with male sperm to form a zygote or fertilized egg.

Correct Answer: B

Rationale: The correct answer is B: Ovum. The ovum is the mature female sex cell that unites with a male sperm during fertilization to form a zygote. Ovary (A) is the organ that produces eggs but is not the actual female sex cell. Gonad (C) is a general term for reproductive organs, not the specific female sex cell. Gametes (D) refer to both male and female sex cells, so it is a broad term and not the specific female sex cell. The ovum is the only choice that accurately represents the tiny female sex cell involved in fertilization.

Correct Answer: C

Rationale: Rationale for correct answer (C): The main function of the testicles is spermatogenesis, which is the process of producing sperm cells. This is a crucial role in male reproductive system. Spermatogenesis occurs in the seminiferous tubules of the testes. Other functions like producing androgenic hormones (choice B) are mainly carried out by the Leydig cells in the testes, not the testicles themselves. While the testicles do play a role in semen production (choice D), this is not their primary function. Therefore, the correct answer is C as it directly relates to the main purpose of the testicles in the male reproductive system.

Correct Answer: C

Rationale: Step-by-step rationale for Choice C (Continues the epididymal duct) being the correct answer: 1. The deferent duct, also known as the vas deferens, is a continuation of the epididymal duct. 2. Sperm mature and are stored in the epididymis before passing into the vas deferens. 3. The vas deferens carries sperm from the epididymis to the ejaculatory duct during ejaculation. Summary: - Choice A is incorrect because the deferent duct does not join with the seminal vesicle duct to form the ejaculatory duct. - Choice B is incorrect as the vas deferens does not continue the rete testis. - Choice D is incorrect as the vas deferens is an intratesticular spermatic duct, not extratesticular.

Correct Answer: A

Rationale: The correct answer is A: head. The spermatozoon is composed of three main parts: head, mid piece or neck, and flagellum. The head contains the nucleus which carries genetic material. The mid piece or neck contains mitochondria for energy production. The flagellum is responsible for sperm motility. In this question, the head is the most essential part of the spermatozoon as it contains the genetic material required for fertilization. The other choices (B: mid piece or neck, C: flagellum, D: body) are incorrect as they are important for sperm function but do not carry the genetic material necessary for fertilization.

Correct Answer: B

Rationale: The correct statement is B: it displays the glandular parenchyma on the inside. The ovary contains specialized tissue called parenchyma, which consists of follicles that house the ova (eggs). This glandular tissue is responsible for producing hormones like estrogen and progesterone. Rationale: - A is incorrect because the ovary is actually covered by a specialized epithelial layer called the germinal epithelium, not a simple epithelium. - C is incorrect because while the ovary does contain follicles at various stages of development, this alone does not encompass the entire function or structure of the ovary. - D is incorrect because the ovary is connected to the Fallopian tube via the infundibulopelvic ligament, not directly by ligaments.