Lobes, genetics, and seed variability

    I personally cannot draw any solid conclusions on the role of lobes in
AG's, but I will speculate that they serve as an organizational structure
rather than playing a genetic role.  Organizing seeds into lobes makes
nutrient transport and seed development more efficient for the plant.  Most
fruits organize their seeds in a specific matter, in which location does not
play a role in genetic makeup.   Also, ovule formation is completely random
genetically speaking.

As for variability of seeds contained within a pumpkin, yes it is quite
expansive, but in the same respect, it is quite limited as well.  When you
add up ALL the genes in a pumpkin (of which there are thousands) then yes,
the variability is incredible.  But when you consider the number of traits
that we are interested in (size, color, shape) then the variability is a
little more limited.

Each female and male will each contain two alleles for a specific gene. 
When gametogenesis occurs (production of ovule or pollen) each parent
donates one of the two alleles to the ovule or pollen grain.  When the ovule
and pollen grain unite, they combine the alleles to form the complete gene. 


Remember that for each gene, the parent can only donate one of two possible
alleles.  So for ONE GENE in a seed, it can have a combination of 2 alleles
that are derived from the 4 possibilities from the parents.

Lets say that the female has the W and X alleles and the male has the Y and
Z alleles.

The possible combinations for the SEEDS are  WY, WZ, XY, XZ.  One allele
from each parent.  There are a maximum of four possibilties for that gene. 
Keep in mind that I am neglecting the whole concept of dominance and
recessiveness.

A TRAIT is made up of one or more genes.  So it depends on the number of
genes controlling a specific trait that determines the degree of variability
in a seed.  In the previous example, there were a maximum of four
possiblities.  Add in another gene for that trait, and I believe the
variability grows exponentially.  Two genes would have 4x4= 16 possiblities.
 A third gene for that trait would have 4x4x4= 64 possibilites. The big
mystery comes down to how many genes control traits such as shape or size. 
I welcome all contributions/criticisms to this argument.










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