Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Can asexual reproduction be the cause of genetic variations

  1. Oct 31, 2016 #1
    In plants , Spores are produced ( asexual reproduction) as a result of meiosis , so there should be genetic variations as meiosis causes genetic variations!! please help to clarify the concept
     
  2. jcsd
  3. Oct 31, 2016 #2

    jim mcnamara

    User Avatar

    Staff: Mentor

    I guess:
    You are talking about Alternation of Generations - gametophyte and sporophyte. And the production of gametes is NOT asexual. So the answer is: yes. Meiosis always "scrambles" DNA in chromosome pairs when crossing over occurs. It is sometimes called recombination. In evolutionary terms it is known as 'meiotic drive'.

    Somewhere you got the word 'spore' misplaced in your understanding. Flowering plants produce meiotically generated spores (gametes): pollen grains, for example. Not part of asexual reproduction.

    Cell division or mitosis is the driving force for asexual reproduction. Gametophytes like molds can make spores by mitosis, even though they are haploid.

    All of this gets messy and confusing to students when you look at fungi, because most times, the organisms we can see are gametophytes - they have half the normal number of chromosomes.
     
    Last edited: Oct 31, 2016
  4. Nov 1, 2016 #3
    But I think that pollen grains are not gametes , they are Spores and the gametes are produced from them by Mitosis.
     

    Attached Files:

  5. Nov 1, 2016 #4

    jim mcnamara

    User Avatar

    Staff: Mentor

    Anything with one n chromosomes is a gamete in the sense of gametophyte. Production of more cells by mitosis does not change that.
    Anything with two n chromosomes is not a gamete in the sense of gametophyte versus sporophyte.

    I see what your drawing shows, and yes they use the word "spore". IMO, bad choice. Why? Because you are confused by it. Spore has multiple meanings. It usually means asexual reproduction. You are correct in that usage. Why? If your instructor thinks that is the correct way to go you are stuck with it.

    If you talk to a Botanist they will explain it a little differently.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Can asexual reproduction be the cause of genetic variations
  1. Asexual reproduction (Replies: 4)

  2. Genetic variation (Replies: 16)

Loading...