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Boy that's a Mouth Full - Try Typing it
Heterozygous vs. Homozygous Loci and Dominant vs. Recessive Genes
When an individual has two identical genes at a locus, it is said to be homozygous (a zygote is a germ cell, e.g. an egg or sperm, and homozygous means the two have the same gene at the same locus). Individuals with different genes at a locus are heterozygous at that locus. For example, individuals that are AA are homozygous, and those that are Aa are heterozygous.
In a heterozygous locus, one of the genes might be dominant, which means that the trait it codes for will be seen and the trait coded for by the other gene (the recessive gene) will not be epxressed. For example, suppose A is dominant and a is recessive. That means whenever an organism has an A at the locus - either AA, Aa, or aA - the attribute coded by A is in effect. The only way the attribute coded by a is seen is if the organism is aa.
Encarta® World English Dictionary © 1999 Microsoft Corporation. All rights reserved. Developed for Microsoft by Bloomsbury Publishing Plc.
lo·cus n
1. a place where something happens
2. a set of points, the positions of which satisfy a set of algebraic conditions
3. the position of a gene in a chromosome
ho·mo·zy·gous adj
having two identical genes at the corresponding loci (AA) of homologous chromosomes
het·er·o·zy·gous adj
used to describe a cell or organism that has two or more different versions (alleles) of at least one of its genes. (Aa) or (aA)
re·ces·sive adj
1. used to describe a gene that produces an effect in an organism only when its matching allele is identical. (aA) + (Aa) or (AA) + (Aa)
2. used to describe a characteristic or trait determined by a recessive gene
3. tending to go backward or to recede
n
1. a recessive gene or trait
2. an organism that has a recessive gene or trait
dominant
"A" being dominant
"a" being recessive
I'm trying to understand - - in this instance "A" being the Color Black
Is this the way it works?
Bull + Cow = Get
AA + Aa = AA Black
AA + aA = Aa Black
AA + aa = Aa Black
Reference See:
Homozygous Paint Horses
http://www.google.com/search?client=safari&rls=en&q=Homozygous+Paint+Horses&ie=UTF-8&oe=UTF-8
Heterozygous vs. Homozygous Loci and Dominant vs. Recessive Genes
When an individual has two identical genes at a locus, it is said to be homozygous (a zygote is a germ cell, e.g. an egg or sperm, and homozygous means the two have the same gene at the same locus). Individuals with different genes at a locus are heterozygous at that locus. For example, individuals that are AA are homozygous, and those that are Aa are heterozygous.
In a heterozygous locus, one of the genes might be dominant, which means that the trait it codes for will be seen and the trait coded for by the other gene (the recessive gene) will not be epxressed. For example, suppose A is dominant and a is recessive. That means whenever an organism has an A at the locus - either AA, Aa, or aA - the attribute coded by A is in effect. The only way the attribute coded by a is seen is if the organism is aa.
Encarta® World English Dictionary © 1999 Microsoft Corporation. All rights reserved. Developed for Microsoft by Bloomsbury Publishing Plc.
lo·cus n
1. a place where something happens
2. a set of points, the positions of which satisfy a set of algebraic conditions
3. the position of a gene in a chromosome
ho·mo·zy·gous adj
having two identical genes at the corresponding loci (AA) of homologous chromosomes
het·er·o·zy·gous adj
used to describe a cell or organism that has two or more different versions (alleles) of at least one of its genes. (Aa) or (aA)
re·ces·sive adj
1. used to describe a gene that produces an effect in an organism only when its matching allele is identical. (aA) + (Aa) or (AA) + (Aa)
2. used to describe a characteristic or trait determined by a recessive gene
3. tending to go backward or to recede
n
1. a recessive gene or trait
2. an organism that has a recessive gene or trait
dominant
"A" being dominant
"a" being recessive
I'm trying to understand - - in this instance "A" being the Color Black
Is this the way it works?
Bull + Cow = Get
AA + Aa = AA Black
AA + aA = Aa Black
AA + aa = Aa Black
Reference See:
Homozygous Paint Horses
http://www.google.com/search?client=safari&rls=en&q=Homozygous+Paint+Horses&ie=UTF-8&oe=UTF-8