2. Assessment
Statements
4.3.1: Define genotype, phenotype, dominant
allele, recessive allele, codominant alleles,
locus, homozygous, heterozygous, carrier and
test cross
4.3.4: Describe ABO blood groups as an
example of codominance and multiple alleles
4.3.5-10
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3. Basic definitions
Genotype: the alleles of an organism
phenotype: the characteristics of an organism
Dominant allele: an allele that has the same
effect on the phenotype whether it is present
in the homozygous or heterozygous state
Recessive allele: an allele that only has an
effect on the phenotype when present in the
homozygous state
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4. Dominant -
Recessive
Phenotype of dominant alleles will show when
one or more allele is dominant
For recessive characters to show, both alleles
must be recessive
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5. Sex-linked
Some characteristics are linked on to the sex
chromosomes
Mostly, X chromosomes carry specific alleles
There could be sex-linked dominant and
recessive characteristics
Hemophiliac and color-blindness are the
commonly used examples of sex-linked
characteristics
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6. Codominant
There are two types of alleles at once
Both characters are shown when both
dominant alleles are present
Cows: When both black and white alleles are
shown they could be dotted
Flowers: When both red and white alleles are
shown they could be pink
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7. As: 4.3.4
Describe ABO blood
groups as an example of
codominance and
multiple alleles
There are three types of
alleles: I^A, I^B, i
A and B alleles are
dominant, i allele is
recessive (represents
blood type O)
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8. THANK YOU
TYPES OF
INHERIT-
ANCE
FYI, THEY ARE CODOMINANT!
DATE CREATOR
11.22.2011 LIZZY KIM
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