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Hi Again,
Yes I understood the question but I attempted to show that a
bullet-proof definition is not readily possible. As with most words, usage
and context define the meaning of a word. A first year Botany text and a
Cryptogamic Botany text would fill in the necessary context.
I vaguely recall that when exposed to this 60+ years ago we learned
about a few extinct or very rare plants that had highly modified leaves that
were almost flower-like in function and bare ovules that gave rise to
structures that were almost seeds etc. And if such intermediate plants had
not been recognized then they would have had to be postulated to be
consistent with evolution.
Precise definitions and Biology are like oil and water. I expect many
pre-school
children would tell you that 1/2 + 1/2 does not equal 2 but the terminology
of meisosis and mitosis says that when the chromosomes of a haploid cell
fuse with those of another haploid cell then the product is diploid.
Is a lichen an organism ?; no. Is it alive ?;yes. Can it reproduce ?;no.
It is way past my bedtime.
Yt, Dave Webster
----- Original Message -----
From: "Gerald" <naturens@zdoit.airpost.net>
To: <naturens@chebucto.ns.ca>
Sent: Tuesday, June 03, 2014 6:29 PM
Subject: Re: [NatureNS] Spores vs. seeds
> Dave,
>
> Thank you for the reply. I was reading Lichens of North America when I
> got confused about seeds versus spore. I did not make clear I wanted a
> text that explained seeds and spore.
>
> My difficulty is that a definiton such as yours, similar to those I
> found elsewhere, is equivocal. I'm an amateur at this. The definitions I
> found led me to conclude some seeds are spores and some spores are
> seeds, and some seeds are not spores and some spores are not seeds. That
> is, seed vs. spore is not a dichotomy.
>
> --
> Gerald
>
> On 6/2/14, 20:25, David & Alison Webster wrote:
>> Hi Gerald & All, June 2, 2014
>> Mainly a seed (at least a typical seed) is a multicellular non motile
>> product of sexual reproduction and has differentiated structures such as
>> cotyledons, plumule and radicle whereas spores can be single-celled or
>> multicellular, the haploid sometimes motile participants of sexual
>> union, or diploid cells or clusters of cells that are generated
>> following this union or asexual diploid cells that are just shed under
>> some conditions like a specialized single-celled botanical dandruff.
>> Many 'primitive' organisms are able to generate resting spores, when
>> conditions become adverse, so they can survive otherwise lethal
>> conditions.
>> The above are distinct from the various multicellular diploid
>> packages for vegetative propagation that are split off from lichens,
>> mosses, liverworts and some vascular plants.
>>
>> Brodo, Sharnoff and Sharnoff (Lichens of North America) is a recent
>> book with good illustrations but difficult to use because species are
>> arranged in alphabetical order so closely related genera, that might
>> readily be confused, are scattered.
>> Yt, Dave Webster, Kentville
>>
>> ----- Original Message ----- From: "Gerald" <naturens@zdoit.airpost.net>
>> To: <naturens@chebucto.ns.ca>
>> Sent: Monday, June 02, 2014 6:41 PM
>> Subject: [NatureNS] Spores vs. seeds
>>
>>
>>> Hi,
>>>
>>> I am learning about lichens. I am starting with spores (decided they
>>> came first). I am trying to understand the difference between a seed and
>>> a spore. I'm not even sure there is a difference. Answers or a good text
>>> suggestion welcome.
>>>
>>> Thanks
>>>
>>> --
>>> Gerald
>>>
>>>
>>> -----
>>> No virus found in this message.
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>>> Version: 2014.0.4592 / Virus Database: 3950/7580 - Release Date:
>>> 05/28/14
>>>
>>
>
>
> -----
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> Checked by AVG - www.avg.com
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