L3-Animal Development and Reproduction

• Protogyny


  Female first
• Protandry


  Male first
• Oysters


  • Born male, grow and become female and lay eggs
  • Some oyster species change sex multiple times
• Fertilization


  Combination of a sperm and an egg
• Internal fertilization


  Occurs inside the body of the female

  
• Orangutans


  • Example of internal fertilization
• External fertilization


  Occurs in aquatic environments where both eggs and sperm are released into the water
• Fish reproduction


  • Example of external fertilization
• Spawning


  One or several females release their eggs and the male(s) release sperm in the same area, at the same time
• Oviparity


  Fertilized eggs are laid outside the female's body and develop there, receiving nourishment from the yolk that is a part of the egg
• Ovoviparity


  Fertilized eggs are retained in the female, but the embryo obtains its nourishment from the egg's yolk and the young are fully developed when they are hatched
• Viviparity


  The young develop within the female, receiving nourishment from the mother's blood through a placenta. The offspring develops in the female and is born alive
• Male reproductive anatomy


  • Scrotum
  • Penis
  • Testes
  • Seminal Vesicles
  • Prostate Gland
  • Bulbourethral Gland
• Scrotum


  • Carry, support and protect the testes
  • Helps to keep the temperature of the testes below the normal body temperature
• Penis


  • Deliver urine, copulating organ
  • For sex and reproduction
• Testes


  • Produce sperm and male hormones
  • Produces spermatozoa (male gametes)
  • Participates with the hypothalamus-pituitary unit in regulating reproductive function

  
• Seminal Vesicles


  • Contribute to semen production
  • Also stores the semen
  • During ejaculation, the fluid from the seminal vesicles is expelled into the ejaculatory duct where it can then move on to mix with sperm and other reproductive fluids
• Prostate Gland


  • Contribute to semen production
  • Produce the fluid that nourishes and transports sperm (seminal fluid)
• Bulbourethral Gland


  Clean urethra at ejaculation
• Testes


  The gamete producing organs of the male reproductive systems. Located in the scrotum (an external skin sac) to achieve the ideal temperature for sperm production (3C lower than the rest of the body)
• Epididymis


  Site where the sperms mature and become capable of moving
• Vas Deferens


  During ejaculation, the sperm are carried from the epididymis to the urethra through the Vas Deferens
• Seminal Vesicle


  Lie between the bladder and rectum. Produce a fluid rich in sugar that provides energy for the sperm. Secrete prostaglandins that help the semen move up to the uterus during mating

  
• Prostate Gland


  Locates below the bladder. Secretes an alkaline fluid that neutralizes the acids in the female reproductive system
• Bulbourethral Gland


  Also called "Cowper's Gland". Secrete an alkaline fluid that neutralizes the traces of acidic urine in the urethra
• Penis


  The male organ that deposits sperm in the female reproductive system during mating. About 3.5ml of semen (300-400M sperms) is expelled during ejaculation (the forceful expulsion of semen)
• Female reproductive anatomy


  • Clitoris
  • Mons pubis
  • Labia Majora
  • Labia Minora
  • Vestibular Gland
  • Ovaries
  • Fallopian Tube
  • Uterus
  • Vagina

  
• Clitoris


  • Sensory organ
  • To give sexual pleasure
• Mons pubis


  • Fatty area overlying public bone
  • Source of cushioning during sexual intercourse
• Labia Majora


  Covers Labia Minora
• Labia Minora


  Covers Vestibules
• Vestibular Gland


  Secrete mucus; lubricates vagina
• Ovaries


  • Carry and develop eggs
  • Make hormones that control your menstrual cycle and pregnancy
• Fallopian Tube


  Transport eggs to uterus
• Uterus


  Support developing embryo
• Vagina


  Common tube for intercourse, birth canal, passing menstrual flow
• Ovaries


  The gamete producing organs of the female reproductive systems
• Fallopian tube


  Also called oviduct. Passageway through which an egg cell moves from the ovary towards the uterus (3 to 4 days)

  
• Uterus


  A hallow, muscular organ. After fertilization, the development of the zygote will take place in the uterus, as well as implantation
• Cervix


  The neck of the uterus is the cervix, which opens to the vagina