Females will have two X-linked alleles (because females are XX), whereas males will only have one X-linked allele (because males are XY). Most X-linked traits in humans are recessive.
Which chromosome symbol combination represents a female?
Individuals having two X chromosomes (XX) are female; individuals having one X chromosome and one Y chromosome (XY) are male. The X chromosome resembles a large autosomal chromosome with a long and a short arm. The Y chromosome has one long arm and a very short second arm.
Do females only carry dominant alleles?
Females carry no copies of Y-linked genes. Diseases caused by mutated genes located on the X chromosome can be inherited in either a dominant or recessive manner. Since males only have one X chromosome, any mutated gene on the X chromosome, dominant or recessive, will result in disease.
What is a genotype for a recessive trait found on the female chromosome?
The genotype for a recessive trait found on the female is XH.
When genes are close together on the same chromosome, they are said to be linked. That means the alleles, or gene versions, already together on one chromosome will be inherited as a unit more frequently than not.
What is the genotype for females?
Genotypic sex refers specifically to an individual’s two sex chromosomes. Most people have either two X chromosomes (genotypic female) or an X and a Y chromosome (genotypic male).
What chromosomes do females have?
Females have two copies of the X chromosome, while males have one X and one Y chromosome. The 22 autosomes are numbered by size. The other two chromosomes, X and Y, are the sex chromosomes. This picture of the human chromosomes lined up in pairs is called a karyotype.
Which allele is dominant?
If the alleles of a gene are different, one allele will be expressed; it is the dominant gene. The effect of the other allele, called recessive, is masked.
What is an example of dominant allele?
Dominant alleles show their effect even if the individual only has one copy of the allele (also known as being heterozygous?). For example, the allele for brown eyes is dominant, therefore you only need one copy of the ‘brown eye’ allele to have brown eyes (although, with two copies you will still have brown eyes).
What is the genotype for a recessive trait?
Only individuals with an aa genotype will express a recessive trait; therefore, offspring must receive one recessive allele from each parent to exhibit a recessive trait. … Let (S) represent the dominant allele, and (s) represent the recessive allele.
Which allele combination represents a male?
X-linked alleles require a specific notation: Xc or X+ where the “+” represents the dominant allele and the lowercase letter the recessive allele. Females will have two X-linked alleles (because females are XX), whereas males will only have one X-linked allele (because males are XY).
What percentage of the female offspring will be a carrier for this recessive disease?
Autosomal recessive inheritance: Two unaffected people who each carry one copy of the altered gene for an autosomal recessive disorder (carriers) have a 25 percent chance with each pregnancy of having a child affected by the disorder.
Is gender an inherited or acquired trait?
Gender is an inherited Trait.