non-mammalian reproduction

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by Rubidium Group 1

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  • 1. The Non-mammalian REPRODUCTIVE SYSTEMIII rubidium group 1

2. Sexual vs Asexual Reproduction

  • Asexual reproduction: Gr. without sex
  • Genes come solely from parent
  • Mitotic cell division
  • Most suitable for favorable and stable environments
  • Fission
  • Budding
  • Regeneration and fragmentation

3. Sexual vs Asexual Reproduction

    • FISSION
    • -separation of a parent into 2 or more individuals of approx. equal size, each with a copy of the parent's genetic material
    • -generally exponential population growth
    • -ex. bacteria, archaea
    • FRAGMENTATION: breaking of body into several pieces
    • REGENERATION: regrowth of lost body parts

4. Sexual vs Asexual Reproduction

    • BUDDING
    • -formation of a new organism by the protrusion of part of another organism
    • -offspring may either detach from parent or remain attached, to eventually form colonies
    • -ex. cnidarians, tunicates, sponges
    • *gemmules-formed when different types of cells clump together withinthe sponge and become surrounded by a protective coat

5. Sexual vs Asexual Reproduction 6. Sexual vs Asexual Reproduction

  • Sexual reproduction: fusion of haploid gametes to form a diploid zygote
  • Requires two organisms
  • Increases genetic variety through gene shuffling
  • Used during times of great stress

7. External and Internal Reproduction

  • External Reproduction: egg is fertilized in the environment
  • More zygotes are produced
  • Situational, but triggered by chemical/behavorial factors (e.g. pheromones)
  • Internal Reproduction: egg is fertilized in the female reproductive tract
  • Less zygotes
  • Parental care increases chances for survival

8. External and Internal Reproduction 9. Different Reproductive Strategies

  • Reproductive cycles
  • Alternatingly asexual/sexual
  • Hermaphroditism
  • Sequential Hermaphroditism
  • Parthenogenesis

10. Different Reproductive Strategies

    • Reproductive cycles
    • -periodic, only certain times of the year/month
    • -allows animals to conserve energy when environment is not favorable for reproduction
    • -related to seasons, hormones
    • -not necessarily for stressful environments
    • -examples: ewes, humans

11. Different Reproductive Strategies

    • Aleternatingly Sexual/Asexual
    • -asexual when conditions are favorable
    • -sexual when environment is stressful
    • -example: aphids, rotifers,Daphnia

12. Different Reproductive Strategies

    • Hermaphroditism
    • - from the the Greek god, Hermes, and the Greek goddess, Aphrodite
    • - solution to difficulties faced by parasites and sessile animals in sexual reproduction
    • - each individual has both male and female reproductive organs
    • -example: tapeworms

13. Different Reproductive Strategies

    • Sequential Hermaphroditism
    • -sex reversal
    • -protogynous: female first
    • -protandrous: male first
    • -associated with size, age, current environment or population needs
    • -example: wrasses

14. Different Reproductive Strategies 15. Different Reproductive Strategies

    • Parthenogenesis
    • -fertilization without sex
    • -egg develops without fertilizing
    • -often produces haploid adults
    • -has a role in social organization
    • - example:Cnemidophorus uniparens

16. Reproductive Systems in Non-mammalians

  • Gonads organs that produce gametes
  • Annelids
  • Separate sexes but gonads are not distinct
  • Eggs and sperm develop from undifferentiated cells lining the coelom
  • When gametes mature, these cells occupy the coelom

17. Reproductive Systems in Non-mammalians Arthropods -males develop sperm in testes, and are conveyed through a coiled duct to two seminal vesicles -females develop eggs in a pair of ovaries and are conveyed to vagina through ducts * spermatheca: sac that stores sperm for long periods of time in female reproductive system Cloaca:common opening of the digestive, excretory, and reproductive system