Sexual reproduction increase
genetic variation in offspring. Which in turn increase the genetic
variability in species. You can see the effects of this genetic
variability if you look at the children in a large familyand note how
each person in unique you know ( not to mention, all the families of all
the sexually reproducing organisms on earth ). And you begin to get a
feel for dramatic genetic impact of sexual reproduction.
MUTATION
DNA polymerase occasionally makes uncorrected mistakes when copying a
cell's genetic information during DNA replication. These mistakes are
called spontaneous mutations and they introduce changes into genetic
code.
CROSSING - OVER
When homologous chromosomes come together prophase I of meiosis, they
exchange bits of DNA with each other. This crossing over result in new
gene combination and new changes for variety.
INDEPENDENT ASSORTMENT
Independent assorment occurd when homologous chromosomes separate during anaphase I of meiosis.
FERTILIZATION
Fertilization presents yet another opportunity for genetic diversity.
Imagine millions of genetically different sperm swimming toward an egg.
NONDISJUNCTION
Nothing's perfect, even in the cellular world, which is why sometimes
meiosis doesn't separate the way they're supposed to, that's called
nondisjunction.
PINK AND BLUE CHROMOSOMES
Ever wish you could've been born the opposite sex so you wouldn't have
to spend so much of your budget on make up or shave your face everyday
every morning?
Sorry, but
that was never really your decision to make, like all others genetic
characters, gender is determined at chromosomal leverl
