Sexual Reproduction in Humans

• What are the three main functions of the male reproductive system?

  Produce sperm, discharge sperm within the female reproductive tract and secrete hormones
• What is spermatogenesis?

  Process of sperm production in testes
• Where does spermatogenesis take place?

  In the seminiferous tubules of the testes
• What does seminal fluid contain?

  Spermatozoa, enzymes, and fructose
• What is the function of the penis?

  Sexual intercourse and urination
• Why is the scrotum important for sperm development?

  It maintains optimal temperatures for sperm
• What is the role of the epididymis?

  Store and carry sperm
• What do seminal vesicles produce?

  Fructose and alkali fluid for sperm
• What is the function of the prostate gland?

  Contributes fluid to nourish sperm
• What are the main functions of the female reproductive system?

  Produce eggs, site for foetus development
• What is the uterus's role in reproduction?

  Site of implantation and foetus development
• What hormones do the ovaries produce?

  Estrogen and progesterone
• What are Fallopian tubes also known as?

  Oviducts
• Where does fertilization usually occur?

  In the Fallopian tubes
• What is the endometrium?

  The lining of the uterine cavity
• What happens to the endometrium if no pregnancy occurs?

  It is shed during menstruation
• What is the cervix's function?

  Allows menstrual flow and directs sperm
• What is spermatogenesis a version of?

  Gametogenesis
• Where does spermatogenesis begin?

  At puberty
• What do Sertoli cells do?

  Support developing spermatozoa
• What is the first stage of sperm production?

  Formation of spermatogonia
• What happens during meiosis I in spermatogenesis?

  Primary spermatocytes divide into secondary spermatocytes
• How many chromosomes do primary spermatocytes have?

  46 chromosomes
• What is produced at the end of meiosis II in spermatogenesis?

  Four haploid spermatids
• What are the three main parts of a sperm cell?

  Head, midpiece, and tail
• What does the acrosome contain?

  Hydrolytic enzymes for fertilization
• What is oogenesis?

  Production of female gametes
• What do primary follicles contain?

  A primary oocyte surrounded by follicular cells
• What happens during ovulation?

  Graafian follicle releases secondary oocyte
• What is the role of the corpus luteum?

  Secretes progesterone after ovulation
• What triggers capacitation in sperm?

  Changes in the vagina/uterus
• What is the acrosome reaction?

  Release of enzymes to penetrate oocyte
• What prevents polyspermy during fertilization?

  Hardening of the zona pellucida
• What is formed after fertilization?

  A diploid zygote
• What happens immediately after the zygote is formed?

  It undergoes repeated mitotic divisions
• What are the stages of oogenesis?

  1. Germinal epithelium cells undergo mitosis to produce oogonia.
  2. Oogonia increase in size and become primary oocytes.
  3. Primary oocytes undergo meiosis I but pause at prophase I.
  4. After puberty, primary oocytes complete meiosis I, forming secondary oocytes and polar bodies.
  5. Secondary oocytes pause at metaphase II until fertilization.
  6. Upon fertilization, secondary oocyte completes meiosis II, forming ovum and polar body.
• What are the steps of fertilization?

  1. Sperm transferred from penis to fallopian tubes.
  2. Capacitation occurs in the vagina/uterus.
  3. Acrosome reaction allows sperm to penetrate oocyte.
  4. Cortical reaction prevents polyspermy.
  5. Completion of meiosis II in secondary oocyte.
  6. Formation of diploid zygote.
• What are the stages of embryo development after fertilization?

  1. Zygote undergoes mitotic divisions.
  2. Formation of blastocyst.
  3. Implantation into the endometrium.
  4. Development of the placenta.
  5. Growth and differentiation of embryonic cells.
• What happens when a sperm contacts the secondary oocyte's membrane?

  The sperm's head fuses with microvilli.
• What is the result of the sperm's genetic material entering the secondary oocyte?

  It leads to the cortical reaction.