Summary Human Development

A snapshot of the summary - Human Development

• 2. The reproductive system in males

• Why are spermatozoa placed 'outside' of the body?

  Spermatozoa like to develop 1 degrees celsius colder than the body temperature of 37 degrees celsius. The testes are located in the scrotum to have this colder temperature.
• What is the structure of the testis?

  The testis consist of seminiferous tubules and connective tissue.
• What are sustentacular (Sertoli) cells?

  Sustentacular (Sertoli) cells sustain and promote development of sperm.
• What are the two types of male germ cells (spermatogonia)?

  Type A: duplicate themselves via mitosis. This is symmetric division.
  Type B: develop into sperm via meiosis. This is asymmetric division.
• What causes variability in meiosis? Why is this necessary?

  Recombination causes variability in meiosis. This is necessary to increase genetic variation.
• What is the acrosomal cup? What does it contain?

  The acrosomal cup is the fusion of the nucleus and the Golgi apparatus. It contains enzymes to penetrate the egg (hyaluronidase & acrosin).
• Why does sperm lack organelles?

  It reduces size and mass and it must absorb nutrients from the surrounding fluid.
• What is the anatomy of a spermatozoon?

  A spermatozoon contains a head, neck, middle piece, and tail.
• What does the head of a spermatozoon consist of?

  The head of a spermatozoon contains the nucleus and chromosomes.
• What does the neck of a spermatozoon consist of?

  Contains centrioles (anterior: mitotic spindle; posterior: continuous microtubules for movement of flagellum).