Objective 1:
Gregor Mendel (optional)
Mendel's 1st law
Mendel's 2nd law
Objectives 4 & 5:
Probability (optional)
Objective 7:
ABO antigens (7a)
Rh factor (7c)
Think you know about blood types? Play the Blood
Typing Game and
find out! (optional)
Objective 8:
Pleiotropy (optional)
You
are what your mother eats.(optional)
Objective 9:
Polygenic inheritance (optional)
Genetics of
Coat Color in Dogs (optional)
Nice site focused on coat
color in the Sheltie (Shetland Sheepdog)
Understand genetic crosses using dog examples
Cat Color
Genetics (optional)
Objective 11:
Pedigree
analysis (optional)
Objective 12:
Phenylketonuria (11d)
Your genes,
your health: genetic disorders
(PKU, Tay-Sachs, CF, sickle cell, etc.)
How is PKU inherited?
Objective 13:
Is there a gene for gender?
Sex determination in non-humans (optional):
Honeybee
sex gene discovered: Sequencing project reveals two different
versions make a female, one a male.
Evolution
of Sex Chromosomes: The Case of the White Campion - researchers
uncover striking parallels in the details of sex chromosome evolution
between
mammals and a far more distant group: plants.
Y chromosome
sequence completed: DNA readout reveals genetic palindromes
safeguard male-defining chromosome. (optional)
Platypus sex is XXX-rated
Objective 17:
Genomic
imprinting in humans (17b)
Silent Struggle: A New Theory of Pregnancy - New research on genomic
imprinting and its evolution (optional)
"The most striking case of large-scale genome imprinting involves
crosses between horses and donkeys. Cross a female horse and a male donkey
and you
get a mule. Cross a male horse and a female donkey and you get a hinny,
altogether a different creature. Clearly, the same genes act out different
roles, depending
on whether they come from mom or dad."
The
Maternal Grandsire Effect: Secretariat, perhaps the greatest thoroughbred
of all time was not matched by his direct offspring,
who by and large were unremarkable. His greatness was passed on through
his daughters, many of whom went on to produce great performers. (optional)
Genomic imprinting (optional): geneimprint.com
Genome
biology: She moves in mysterious ways - The human X chromosome is
a study in contradictions. The detailed sequence of the X, and a survey of
inactivated genes in females, help to illuminate
this unique 'evolutionary space'.
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Polygenic Inheritance
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Wild Columbine: an example
of a trait being affected by more than one gene.
Columbine
flowers are the state flower
of Colorado. San Juan mountains, Colorado.
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Sometimes when more than one gene influences a given trait, their
effects on that trait are very similar. For example, in the wild columbine
(Aquilegia canadensis),
gene M can have allele M1 or M2 (neither is dominant),
while gene N also has two different alleles available, N1 and N2 (again,
neither
is dominant to the
other). The presence of any M1 allele makes the plant taller, while
any M2 makes the plant shorter; similarly, any N1 makes
the plant
taller, while
any N2 makes
the plant shorter. The very shortest plant would have this genotype: M2/M2 N2/N2while
the very tallest plant would have this genotype: M1/M1 N1/N1.
The genotype M1/M2 N1/N2would be
exactly in between.
The nine different
possible
genotypes
and the plant heights they produce could be graphed as follows:
If a trait were affected by many more loci with similar effects, the variation
in height would become continuous; every possible height between short and
tall would be represented by some genotype. Such variation is called polygenic inheritance.
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