alternation of generation

[andyjl]

for plants, the cycle of going from diploid sporophyte to a haploid gametophyte appears to be the same.

for sexual reproduction it looks like gametophytes reproduce by meiosis while sporophyte generation reproduces mitosis

for asexual reproduction.. gametophytes reproduce by mitosis while sporophyte generation reproduces by meiosis.

am I right about this and this is the only main difference?

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[andyjl]

ignore that above question...

i have a new one.

in the kaplan book (p 533) it says that "gametophytes reproduce sexually while the sporophyte generation reproduces asexually"

is that a misprint?

shouldn't it say gametophytes reproduce asexually while sporophyte generation reproduces sexually?

 

[DailyDrivenTJ]

If gametophyte reproduce asexually then it can only produce haploid offsprings like itself and you will never have alternation of generation involving diploid number of chromosomes.

 

[DentalKitty]

This is the info I have from the Kaplan white book and my textbook:

The sporophyte (2N) undergoes meiosis to form haploid spores.
The spores (N) undergo mitosis to form gametophytes (N).
The gametophytes undergo mitosis to form gametes (N).
The gametes fuse, and the zygote divides mitotically to form the sporophyte (2N).

Now the confusion (for me anyway) was assigning sexual and asexual to the phases because sexual reproduction usually involves both meiosis and fertilization. Here we have the sporophyte undergoing meiosis and the gameteophytes/gametes fusing and completing fertilization. But from what I've read, it appears that it's the fertilization that's the most important, so it's the gametophytes/gametes fusing to form the diploid zygote that is considered sexual. While the sporophytes producing haploid spores is asexual. Hopefully this helps!