Are alleles BB homozygous or heterozygous?

An organism with two dominant alleles for a trait is said to have a homozygous dominant genotype. Using the eye color example, this genotype is written BB. An organism with one dominant allele and one recessive allele is said to have a heterozygous genotype. In our example, this genotype is written Bb.

Are alleles homozygous?

If the alleles are identical, you’re homozygous for that specific gene. For instance, it could mean you have two alleles for the gene that causes brown eyes. Some alleles are dominant, while others are recessive. … You either have two dominant alleles (homozygous dominant) or two recessive alleles (homozygous recessive).

Are alleles heterozygous?

An allele is one of two or more versions of a gene. An individual inherits two alleles for each gene, one from each parent. If the two alleles are the same, the individual is homozygous for that gene. If the alleles are different, the individual is heterozygous.

What phenotype is BB?

The physical appearance of the genotype is called the phenotype. For example, children with the genotypes ‘BB’ and ‘Bb’ have brown-eye phenotypes, whereas a child with two blue-eye alleles and the genotype ‘bb’ has blue eyes and a blue-eye phenotype.

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What is heterozygous and homozygous?

Heterozygous refers to having inherited different forms of a particular gene from each parent. A heterozygous genotype stands in contrast to a homozygous genotype, where an individual inherits identical forms of a particular gene from each parent.

What is heterozygous and homozygous examples?

Heterozygous means that an organism has two different alleles of a gene. For example, pea plants can have red flowers and either be homozygous dominant (red-red), or heterozygous (red-white). If they have white flowers, then they are homozygous recessive (white-white). Carriers are always heterozygous.

What are alleles example?

Alleles are different forms of the same gene. … An example of alleles for flower color in pea plants are the dominant purple allele, and the recessive white allele; for height they are the dominant tall allele and recessive short allele; for pea color, they are the dominant yellow allele and recessive green allele.

What is an example of a heterozygous?

If the two versions are different, you have a heterozygous genotype for that gene. For example, being heterozygous for hair color could mean you have one allele for red hair and one allele for brown hair. The relationship between the two alleles affects which traits are expressed.

Are alleles chromosomes?

An allele is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosome. Humans are called diploid organisms because they have two alleles at each genetic locus, with one allele inherited from each parent.

What is homozygous biology?

(HOH-moh-ZY-gus JEE-noh-tipe) The presence of two identical alleles at a particular gene locus. A homozygous genotype may include two normal alleles or two alleles that have the same variant.

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Which genotype is homozygous dominant?

An organism with two dominant alleles for a trait is said to have a homozygous dominant genotype. Using the eye color example, this genotype is written BB. An organism with one dominant allele and one recessive allele is said to have a heterozygous genotype. In our example, this genotype is written Bb.

What are alleles quizlet?

An allele is an alternative form of a gene (one member of a pair) that is located at a specific position on a specific chromosome. These DNA codings determine distinct traits that can be passed on from parents to offspring.

Why are BB and BB considered homozygous combinations?

The first is homozygous, which means two copies of the same allele, like BB for two dominant alleles or bb for two recessive alleles. The other possible combination is heterozygous, which means one of each type of allele, like Bb for one dominant and one recessive allele.

What do the alleles BB mean to geneticists?

An individual that contains two different alleles of a gene is heterozygous. Examples. A cow that has two alleles for a red coat is homozygous (bb). A bull with two alleles for a black coat is homozygous (BB).