Spermatogenesis

• Spermatogenesis


  Formation of spermatozoa
• What is the male gamete in humans known as?

  Spermatozoa
• How many spermatozoa does each primordial germ cell result in?

  Each primordial germ cell results in large numbers of spermatozoa
• Order of cell formation in spermatogenesis

  • Primordial germ cell
  • Spermatogonia
  • Primary spermatocyte
  • Secondary spermatocytes
  • Spermatids
  • Spermatozoa
• Process of spermatogenesis

  • Primordial germ cell undergoes several rounds of mitosis to form spermatogonia
  • Spermatogonia undergo growth but no division (with a longer G1 phase) to form a primary spermatocyte
  • The primary spermatocyte undergoes half of a meiosis (P1,M1,A1,T1) to form secondary spermatocytes
  • Th secondary spermatocytes undergo the second half of meiosis (P2,M2,A2,T2) to form spermatids
  • The spermatids undergo differentiation to form spermatozoa
• What are the characteristics of spermatozoa?

  Many, mini, motile
• Adaptations of spermatozoa

  • Acrosome - contains enzymes to penetrate ovum
  • Mitochondria in middle section - provides ATP
  • Nucleus - genetic material is condensed, so less energy is required to transport it
  • Microtubules - provide whip-like movements
  • Flagellum - rotates rapidly to propel the cell
• Is a primary spermatocyte a diploid or haploid cell?

  Diploid
• Are the spermatogonia diploid or haploid cells?

  Diploid
• Are the spermatids diploid or haploid cells?

  Haploid
• What process takes the primordial germ cell into spermatogonia?

  Mitosis
• What process takes the spermatids into spermatozoa?

  Differentiation