Question 1: Fill in the blanks:
(a) Humans reproduce sexually. (asexually/sexually)
(b) Humans are viviparous. (oviparous/viviparous/ovoviviparous)
(c) Fertilization is internal in humans. (external/internal)
(d) Male and female gametes are haploid. (diploid/haploid)
(e) Zygote is diploid. (diploid/haploid)
(f) The process of release of the ovum from a mature follicle is called ovulation.
(g) Ovulation is induced by a hormone called the luteinizing hormone (LH).
(h) The fusion of the male and the female gametes is called fertilization.
(i) Fertilization takes place in the ampulla of oviduct.
(j) The zygote divides to form blastocyst, which is implanted in uterus.
(k) The structure which provides vascular connection between the fetus and uterus
is called placenta.
Question 2: Draw a labeled diagram of male reproductive system.
Question 3: Draw a labeled diagram of male reproductive system.
Question 4: Write two major functions each of testis and ovary.
Ans: Functions of the Testis:
(a) Production of sperms or spermatozoa by the process of spermatogenesis.
(b) Production of male sex hormone, called androgen/testosterone, by Leydig cells.
Functions of the ovary:
(a) They produce female gametes called ova by the process of oogenesis.
(b) Production of female sex hormones, estrogen and progesterone. Which are responsible feminine characters.
Question 5: Describe the structure of a seminiferous tubule.
Ans: Seminiferous tubules are highly coiled structure located in the testicular lobule help in the production of sperms. Each seminiferous tubule is lined by germinal epithelium. It is lined on its inner side by two types of cells namely spermatogonia and Sertoli cells respectively.
Spermatogonia are male germ cells which produce primary spermatocytes by meiotic divisions. Primary spermatocytes undergo further meiotic division to form secondary spermatocytes and finally, spermatids. Spermatids later metamorphoses into male gametes called spermatozoa.
Sertoli cells are known as nurse cells of the testes as they provide nourishment to the germ cells. There are large polygonal cells known as interstitial cells or Leydig cells just adjacent to seminiferous tubules. These cells secrete the male hormone called testosterone.