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In fruit files one genotype for red eyes is written XrXr. the R stands for the dominant allele for red eyes what does the X stand for?
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In fruit flies one genotype for red eyes is written XRXR. The R stands for the dominant allele for red eyes. What does the X stand for?
Male reproduction system
What stands for a dominant allele?
a CAPITAL letter
What is the difference between a dominant gene and a recessive gene?
In some but not all cases a dominant gene is a functional version (allele) of that gene while a recessive gene is a nonfunctional (or less functional) version (allele) of that gene. As the dominant gene produces a fully normally functioning protein if it is inherited in even just one copy that protein will "dominate" over the protein produced (if any is produced) by the recessive gene. Sometimes there are multiple different dominant alleles and/or multiple different recessive alleles of a specific gene (e.g. human blood types have 2 dominant alleles: A and B that produce different antigen proteins and 1 recessive allele: O that produces no antigen protein).
What stands for recess?
a recessive allele is shown using a lower case letter a dominant allele is shown using a capital letter
How do you write the genotype for a trait?
Genotypes are written differently depending on what gene you are referring to. A capital letter means that allele is dominant over an allele written with a lower case letter. For example B is dominant over b. Some genotypes are written using a superscript, such as IAIB for the genotype of a person with blood type AB. Or HbsHbs for a person with sickle cell anaemia (compared to HbSHbS for a person without sickle cell). In this case Hb stands for haemoglobin. Usually the letters chosen relate to the trait involved... for example, if talking about tall plants T would be used to represent the tall allele and t would represent the short allele.
How would you write an allele that is heterozygous?
Representing heterozygote allele characteristics depends on the nature of the heterozygote.If one of the alleles is dominant, and the other recessive, the genotype is written as Aa - where the capital letter (A) represents the dominant allele, and the lower case letter (a) represents the recessive allele. The dominant (upper case) allele is always written first.However, the genotype cannot be written in this way if both alleles are codominant (neither one is dominant or recessive). In this case, the convention is to choose a letter to refer to the flower-color-locus as a whole. You would then add different superscript letters to denote the different alleles.For example, you could choose the letter A to refer to the flower-color-locus, and then choose C and D as the two co-dominant alleles. This genotype would be written as ACAD.
What stands for dominant allele?
Normally a dominant allele is represented by a capital letter. It can be any letter used. Example; Brown hair is dominant and blond is recessive. B represents the dominant allele (brown) and b represents the recessive (blond) in Bb. You can have any combination of two alleles; BB, Bb, or bb. BB would have brown hair, Bb would have brown hair or a mix, and bb would have blond hair. Instead of B we could have used T or any other letter.
In the pair Tt the capital T represents what gene?
I'm not 100% sure what you're talking about here, but this looks like alleles, not genes. For every gene, there is one copy on each of a pair of chromosomes. The gene can take different forms, called alleles. In the "simple" case, there are only two possible alleles - dominant and recessive. When geneticists are analyzing the probability that an offspring will have the trait in question, they use a capital letter to indicate the dominant allele and a lower-case letter to indicate the recessive allele. The letter used is usually somehow representative of the trait. For Example, T (whether upper or lower case) might refer to a gene that has something to do with tongue. But there is no standard set of letters used to designate specific genes in this context. The T and t in this case could represent any gene, though the T clearly represents the dominant allele and the t represents the recessive allele.By the way, in a simple, one-gene, dominant/recessive case an individual with one Dominant and one Recessive gene (Tt genotype) would have the trait in question, because the dominant allele overrides the recessive one. Only a person with a tt genotype would lack the trait.
In a Punnett square a capital letter stands for a allele.?
Capital letters on Punnett Squares represent dominant genes, while lowercase letters represent recessive genes. For example, if the trait "T" is a tall gene and the trait "t" is a short gene. When you get your results (if both parents are heterozygous for tallness, Tt) you get four possible results, 1 TT (homozygous tall), 2 Tt (twice, heterozygous tall Tt), and 1 tt (homozygous short). If there is a dominant gene there, that gene will be displayed. Only if there are two recessive genes will the recessive trait be displayed.
What is the phenotype of AAA?
It's impossible to say without more information. The genotype AA is called homozygous dominant for the trait that is encoded by the letter A (or a). Whatever trait A stands for on your homework, the answer is the dominant one is expressed in the phenotype.
In a punnet square a small letter stands for what type of allele?
A small letter stands for a recessive allele.
What phenotype does an individual with a homozygous recessive genotype exhibit?
For what trait? Phenotype means the way in which a gene is expressed ie hair colour, kidney function, ear shape. Homozygous means that both genes for that trait are the same. A recessive gene is one that would not be the phenotype if there was a dominant gene paired with it. So the individual has genes for a trait that are the same, and thus expressed, but they wouldn't be if they had only one of that gene.
