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Can a sex-linked allele be dominant?
Yes, a sex-linked allele can be dominant. For example, if a gene on the X chromosome is dominant, females who inherit the allele will express the trait, while males only need one copy of the dominant allele to show the trait since they have only one X chromosome.
Does sickle cell disease require two allele or multiple alleles?
Sickle cell disease is an autosomal reccessive sexlinked trait so, a female msut have 2 recessive alleles to have the trait and a male needs only one allele (this is because there is no corresponding site for this allele on the Y chromosome. The female can be a carrier of the disorder with the defective allele on one X chromosome and a normal allele on the other X chromosome. Female carrriers can have a mixture of normal and abnormal redblood cells.
What genotype must the person have who possessed the recessive phenotypes?
The genotype is homozygous recessive or the recessive trait is on the X chromosome and has no corresponding allele on the Y chromosome.
Why does a sex-linked trait only require one recessive allele on the X chromosome of a male to show the phenotype?
Because males have only one X chromosome, any recessive allele present on that X chromosome will be expressed in the phenotype. In females, who have two X chromosomes, the presence of a dominant allele on one X chromosome can mask the expression of a recessive allele on the other X chromosome.
What unusual result suggested that the eye-color trait is located on the X chromosome?
The unusual result was that in a family, all males had the same eye color as their mothers. This suggested that the gene for eye color is linked to the X chromosome because males inherit their X chromosome from their mothers.
Which trait will a male exhibit if he carries a recessive allele on the X chromosome?
A male will exhibit the trait associated with the recessive allele on the X chromosome if he only carries one copy of that allele. This is because males have only one X chromosome, so they will express any recessive alleles present on it.
What is the difference between the dominant and recessive allele for a trait?
An individual must have 2 recessive alleles in order for a trait to show up. One must only have 1 dominant allele in order for a trait to occur.
Can a sex-linked allele be dominant?
Yes, a sex-linked allele can be dominant. For example, if a gene on the X chromosome is dominant, females who inherit the allele will express the trait, while males only need one copy of the dominant allele to show the trait since they have only one X chromosome.
How many copies of a sex linked recessive allele does a male need to exbit the trait?
A male only needs one copy of a sex-linked recessive allele to exhibit the trait because males have only one X chromosome. If the allele is present on the X chromosome, it will be expressed in males.
Snice the allele for colorblindness is located on the x chromosome which type of trait is colorblindness?
Sex linked
Does sickle cell disease require two allele or multiple alleles?
Sickle cell disease is an autosomal reccessive sexlinked trait so, a female msut have 2 recessive alleles to have the trait and a male needs only one allele (this is because there is no corresponding site for this allele on the Y chromosome. The female can be a carrier of the disorder with the defective allele on one X chromosome and a normal allele on the other X chromosome. Female carrriers can have a mixture of normal and abnormal redblood cells.
What genotype must the person have who possessed the recessive phenotypes?
The genotype is homozygous recessive or the recessive trait is on the X chromosome and has no corresponding allele on the Y chromosome.
Why does a sex-linked trait only require one recessive allele on the X chromosome of a male to show the phenotype?
Because males have only one X chromosome, any recessive allele present on that X chromosome will be expressed in the phenotype. In females, who have two X chromosomes, the presence of a dominant allele on one X chromosome can mask the expression of a recessive allele on the other X chromosome.
Why are traits controlled by recessive alleles on the X chromosomes are more common in males then in females?
In males, they only have one X chromosome, so if they inherit a recessive allele for a certain trait on their X chromosome, it will be expressed because there is no corresponding dominant allele on the Y chromosome to mask it. Females have two X chromosomes, so even if they inherit a recessive allele on one X chromosome, the dominant allele on the other X chromosome can mask its expression.
What unusual result suggested that the eye-color trait is located on the X chromosome?
The unusual result was that in a family, all males had the same eye color as their mothers. This suggested that the gene for eye color is linked to the X chromosome because males inherit their X chromosome from their mothers.
What is is the principal of dominance?
The principle of dominance states that in a heterozygous individual for a trait, only one allele (dominant allele) is expressed in the phenotype, masking the expression of the other allele (recessive allele). This dominance relationship is seen in Mendelian inheritance patterns.
Colorblindness is more common in males than in females because the allele for colorblindness is?
the allele for colorblindness is ressecive NOT dominant. more common in males because they have one x chromosome and women have two, if a deformity is found on the x chromosome in a woman, it can be masked by the other, but still have some sort of side effects, in a male, since he has one, he is effected the most. he has no other genes to mask it.
