Reproductive system

• The male reproductive system consists of the testes, scrotum, epididymis, vas deferens, urethra, penis, sperm ducts, and accessory glands
• The testes produce male sex cells called sperm cells
• Sperm cells develop inside the seminiferous tubules in the testes
• The scrotum is a bag of skin that contains the testes and is located under the penis
• The dartos and cremaster muscles in the scrotum help maintain its temperature
• Mature sperm cells are stored in the epididymis and are released through ejaculation
• During ejaculation, sperm cells move from the epididymis to the vas deferens, then to the urethra, and out of the body
• Vasectomy is a method of birth control that involves cutting or blocking the vas deferens to prevent sperm cells from being transported out of the body
• The penis is a tube-shaped organ that contains the urethra for passing urine and semen out of the body
• Circumcision involves the partial or complete removal of the prepuce to expose the glans penis
• Accessory glands in the male reproductive system secrete substances that aid in nourishing sperm cells and fertilization
• The male reproductive system produces, develops, and matures sperm cells and safely deposits them into the female reproductive tract
• The primary male sex hormone is testosterone, produced by the testes
• The male reproductive system is specialized for the production of sperm cells and their deposition into the female reproductive tract
• The type of gametogenesis in male organisms is known as spermatogenesis
• The female reproductive system can be divided into internal and external parts
• • Has a very soft lining that holds the fertilized egg and nurtures it until it becomes a fetus
  • The uterine wall has three distinct layers: the perimetrium, the myometrium, and the endometrium
  • The endometrium is the layer that sheds off during menstruation
  • Fallopian Tubes:
  • Connect the ovaries to the uterus
  • Primary function is to transport the egg cells to the uterus
  • Ovaries:
  • Female gonad that contains the egg cells
  • Produces the female sex hormones estrogen and progesterone
• Internal parts:

  • Vagina:
  • An elastic, muscular canal that connects the external reproductive system to the cervix
  • Naturally moderately acidic for protection
  • Cervix:
  • A muscle that holds the fetus during pregnancy
  • Expands once the baby is ready to be born
  • Contains cervical mucus that facilitates the transport and nourishment of sperm to aid in fertilization
  • Can be used as an indicator of a woman’s fertility
  • Uterus:
  • A hollow muscular organ that lies between the urinary bladder and the rectum
• External parts:

  • Labia:
  • Labia majora encloses and protects all the external reproductive organs
  • Labia minora surrounds the openings of the vagina and urethra
  • Mons Pubis and Clitoris:
  • Clitoris:
  • Small, sensitive protrusion at which the two labia minora meet
  • Mons Pubis:
  • Layer of fat that covers part of the pubic bones
• Roles of the Female Reproductive System:

  • Responsible for the nourishment and development of the female gametes
  • Responsible for maintaining the necessary conditions for fertilization to occur
  • Produces different hormones that are used for signaling
• General Functions of the Female Reproductive System:

  • Egg cell production
  • Fertilization
  • Development of the zygote into a new organism
• True or False:

  • Estrogen and progesterone aid in pregnancy: True
  • The clitoris has a significant reproductive function: False
  • The ovary contains the egg cells: True
  • Oogenesis happens in the ovaries: True
  • The fallopian tubes contain urine: False
• Puberty in males is controlled by follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
• FSH and LH are released in response to gonadotropin-releasing hormone (GnRH) from the hypothalamus
• FSH stimulates Sertoli cells in the testes to promote spermatogenesis
• LH stimulates interstitial cells in the testes to produce and release testosterone into the testes and bloodstream
• Testosterone is the primary male sex hormone responsible for the secondary sex characteristics that develop in males during adolescence
• Negative feedback occurs when the body acts to reverse a change that is sensed
• Sertoli cells produce inhibin, which is released into the blood when the sperm count is high
• Inhibin inhibits the release of GnRH and FSH, slowing down spermatogenesis
• Positive feedback occurs when an initial stimulus or response further increases its intensity
• Activin is responsible for further promoting the release of FSH
• Spermatogenesis is the specific type of gametogenesis that occurs in males, primarily initiated and controlled by testosterone
• Puberty typically starts at ages 8–13 for females and about 9–14 for males
• Puberty prepares a person for reproductive maturity
• Reproductive maturity refers to the physical capability of a person to reproduce
• Primary sex characteristics refer to organs specifically needed for reproduction:

  • In females: vagina, uterus, and ovaries
  • In males: penis and testes
• Secondary sex characteristics are the physical characteristics that develop during puberty:

  • Growth of armpit hair
  • Growth of hair in different parts of the body
  • Development of breasts in females
• Gonadarche refers to the development of the reproductive organs, or gonads, during puberty:

  • Gonads in males are the testes
  • Gonads in females are the ovaries
  • When the brain releases pituitary gonadotropins, the gonads grow and mature
• Hormones have both an organizational and activational role in puberty:

  • Organizational role primes the body to behave in a certain way once puberty begins
  • Activational role triggers certain behavioral and physical changes