Homozygous or heterozygous are terms used to describe the genotype of a diploid organism at a locus of the DNA. Homozygous means that the organism has the same two alleles at that locus denoted by AA for dominant alleles or AA for recessive. Heterozygous means that the organism has two different alleles at that locus and is denoted Aa.
A homozygous dominant genotype means that both alleles for a trait are dominant. A heterozygous genotype means that one allele is dominant and the other is recessive. A heterozygous genotype will express the dominant phenotype, not the recessive phenotype.
it's to do with genes, a homozygous organism has two alleles that are the same, whereas a heterozygous organism will have two different alleles. eg, on a chromosome for eye colour, a homozygous example would have both alleles for say, blue eyes. a heterozygous example would have an allele for blue and an allele for brown, where brown would be dominant, reccesive, or cooperative.
Well actually not necessarily. An individual can be homozygous or heterozygous dominant for a trait. As long as they have that dominant allele in that specific genetic trait, they will automatically express the dominant phenotype. If a person is homozygous dominant, it just means that they will pass on both dominant traits to the offspring. If a person is heterozygous dominant , it means that they will pass on both a dominant and recessive trait to their offspring.Hope that helps ! =D
A dihybrid cross for the parental generation would look as follows: A a A AA Aa a Aa aa Indicating three different genotypes, AA, Aa and aa. These three genotypes would be expressed in two phenotypes: 75% of offspring would express the dominant widow's peak (AA and Aa), while 25% of offspring would express the recessive straight hairline (aa).
No, because he or she cannot pass the gene on to his or her offspring (because he or she does not have a copy of the gene).
A homozygous dominant genotype means that both alleles for a trait are dominant. A heterozygous genotype means that one allele is dominant and the other is recessive. A heterozygous genotype will express the dominant phenotype, not the recessive phenotype.
It is easier to analyze genotype by observing phenotype in organisms with incomplete dominance (also known as codominance), because in incomplete dominance the individual will show a specific phenotype for each situation, whether it is homozygous dominant, heterozygous, or homozygous recessive. For example, in flowers, such as the ones that Mendel studied, a homozygous dominant flower will be red, a homozygous recessive flower will be white, and a heterozygous flower will be pink. In complete dominance, a heterozygous will only express the dominant phenotype, as opposed to incomplete dominance, in which a heterozygous individual will express a phenotype that is representative of both of the dominant and recessive traits. Because heterozygous individuals in complete dominance express the dominant phenotype, it is hard to determine whether the genotype is homozygous dominant or heterozygous for the trait. Hope this helps!
it's to do with genes, a homozygous organism has two alleles that are the same, whereas a heterozygous organism will have two different alleles. eg, on a chromosome for eye colour, a homozygous example would have both alleles for say, blue eyes. a heterozygous example would have an allele for blue and an allele for brown, where brown would be dominant, reccesive, or cooperative.
The different forms of a gene are called alleles. In Mendelian genetics, a gene has a dominant allele and a recessive allele. The dominant allele masks the recessive allele if present. So there are two possible dominant genotypes: homozygous dominant, in which both dominant alleles are present; and heterozygous, in which one allele is dominant and the other allele is recessive. The only way to express a recessive trait is to have the homozygous recessive genotype.
The carrier must be Homozygous because if he were hetero it must be Hh and the dominant gene is expressed but homozygous gives them the possibility of hh (only a carrier) or HH (definitely a carrier) Don't totally understand the previous answer; however, I understand the question to mean that you want to know if you are homozygous or heterozygous for a certain trait. If you express a recessive phenotype, that is you have blue eyes for example, you are definitely homozygous for that trait. If one of your parents has a recessive trait, like blue eyes, and the other parent expresses a dominant trait, like brown eyes, AND if you have brown eyes, you can be sure that you are heterozygous. Otherwise it is impossible to tell until you have children. Then you can work backwards from you and your spouse, look at their parents and your parents and then figure the only possible way all those conditions could exist is if you are heterozygous or if you are homozygous for that trait.
That is heterozygous. Some scientist call these "hybrids"(no joke)The person is heterozygous for that trait and will have the dominant phenotype.An organism with both a dominant and recessive allele for a specific trait is called an heterozygote. They are heterozygous for this trait.
Well actually not necessarily. An individual can be homozygous or heterozygous dominant for a trait. As long as they have that dominant allele in that specific genetic trait, they will automatically express the dominant phenotype. If a person is homozygous dominant, it just means that they will pass on both dominant traits to the offspring. If a person is heterozygous dominant , it means that they will pass on both a dominant and recessive trait to their offspring.Hope that helps ! =D
You express 69000 in scientific notation as 6.9 × 104
yes.
how to express scientific notation to a simle number
Not entirely sure what you meant on that one, but I'll try and answer it. Genes have a genotype and a phenotype. (spelling?) A genotype is the "official label for the gene" (i.e. Tt, TT, tt) and phenotype descibes the appearance (i.e. homozygous tall, heterozygous tall, heterozygous short...) Hope this helps!
Let's take red-green color vision as an example. You could use the letter n to represent the dominant and recessive alleles. You could use a capital letter N to represent the normal allele, which is dominant, and a lowercase letter n to represent the defective allele, which is recessive. The genotypes for the sex-linked trait would be as follows: female, homozygous dominant: XNXN; female, heterozygous: XNXn; male dominant, XNY; male recessive, XnY.