No. An allele is the tip of a chromosome.
An individual with a recessive disease-causing allele on one chromosome and a normal allele on the other chromosome is referred to as a heterozygote for that gene. Since the disease is recessive, the normal allele typically masks the effects of the recessive allele, meaning the individual usually does not exhibit symptoms of the disease. However, they can still pass the recessive allele to their offspring.
An allele is an alternative form of a gene that is found at the same location on a chromosome.
True. In females, who have two X chromosomes, a recessive allele on one X can be masked by a dominant allele on the other X. However, since males have one X and one Y chromosome, any recessive allele on their single X chromosome has no matching allele on the Y chromosome, making them more likely to express traits associated with those recessive alleles.
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.
The only difference in the chromosome is the presence of the allele that results in an individual with acondroplastic dwarfism. The chromosome affects the structure of the organism, the allele affects the growth plates of the long bones resulting shortened limbs.
An individual with a recessive disease-causing allele on one chromosome and a normal allele on the other chromosome is referred to as a heterozygote for that gene. Since the disease is recessive, the normal allele typically masks the effects of the recessive allele, meaning the individual usually does not exhibit symptoms of the disease. However, they can still pass the recessive allele to their offspring.
An allele is an alternative form of a gene that is found at the same location on a chromosome.
A single recessive allele will be expressed in a male if he inherits that allele on his only X chromosome, as males have one X and one Y chromosome. This is because the presence of the recessive allele on the X chromosome has no dominant allele to mask its expression.
True. In females, who have two X chromosomes, a recessive allele on one X can be masked by a dominant allele on the other X. However, since males have one X and one Y chromosome, any recessive allele on their single X chromosome has no matching allele on the Y chromosome, making them more likely to express traits associated with those recessive alleles.
An allele on either X or Y could be dominant over the allele on the other chromosome, but it is more common for the allele on the X to be dominant, because the Y chromosome is much smaller than the X and contains fewer genes. In many cases, there is no allele for a particular gene on the Y chromosome; so whatever allele is on the Y will be dominant.
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.
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.
When a harmful allele is carried on the X chromosome, it can lead to specific genetic disorders, particularly in males, who have only one X chromosome (XY). If a male inherits the harmful allele, he will express the associated trait or disorder because he lacks a second X chromosome that could mask its effects. Females, having two X chromosomes (XX), may be carriers of the harmful allele without showing symptoms if the second X chromosome carries a normal allele. However, if a female inherits two copies of the harmful allele, she will express the disorder as well.
A male carrying a recessive allele on the X chromosome will exhibit the recessive trait. This is because the Y chromosome generally does not have matching genes for the X chromosome, unlike the other 22 pairs if chromosomes in the nucleus.
The only difference in the chromosome is the presence of the allele that results in an individual with acondroplastic dwarfism. The chromosome affects the structure of the organism, the allele affects the growth plates of the long bones resulting shortened limbs.
An example of a heterozygous chromosome is having one chromosome with a dominant allele and the other with a recessive allele for a particular gene. This can lead to different traits expressed depending on the dominant or recessive nature of the alleles.
The recessive allele that most often remains on the same chromosome as the dominant allele A is typically referred to as the "linked recessive allele." This occurs due to genetic linkage, where two genes located close together on the same chromosome tend to be inherited together during meiosis. The degree of linkage can be influenced by factors such as recombination frequency, but alleles that are physically close on a chromosome are more likely to be passed on together.