Are red eyes in fruit flies dominant?
Red eye color is wild-type and is dominant to white eye color. Eye color in Drosophila was one of the first X-linked traits to be identified. Thomas Hunt Morgan mapped this trait to the X chromosome in 1910.
Is the red eye gene dominant or recessive?
Example 1: In fruit flies, the gene for red eyes is dominant over the gene for white eyes. The trait is sex-linked on the X chromosome. Cross a homozygous, red-eyed female with a white-eyed male.
What happens when you cross a white eyed female fruit fly with a red eyed male fruit fly?
A reciprocal cross between white-eyed females and red-eyed males gives an F1 in which all the females are red eyed, but all the males are white eyed. The F2 consists of one-half red-eyed and one-half white-eyed flies of both sexes.
When both of the traits are dominant which causes both traits to show up in the organism?
Genetics
| Question | Answer |
|---|---|
| An allele that is hidden whenever the dominant allele is present | Recessive Allele |
| One whose trait always shows up in the organism when the allele is present | Dominant Allele |
| An organism who has two identical alleles for a trait | Homozygous |
| An organism who has two different alleles for a trait | Heterozygous |
Are dominant characteristics more frequent in a population?
1. No, the dominant characteristics are not always more frequent in a population than recessive characteristics because a trait is dominant does not mean that it is present in the population to a greater extent. Therefore, many more people possess both recessive traits for the number of fingers they possess.
Is anyone dominant for every trait?
No organism has all dominant or all recessive genes. An organism may be pure in certain traits and hybrid others. Remember, that a dominant trait in one kind of organism may be a recessive trait in another organism. 1.
What determines if a phenotype occurs in a population?
Explanation: The occurrence of any phenotype is dependent on the allele. If the allele is dominant, there are high chances of occurrence of a particular phenotype again and again.
Is it possible to determine the genotype of a person showing a dominant phenotype?
Bottom line is you can’t always figure out genotype from phenotype with a dominant trait because dominant traits can happen with two different genotypes.
How do you determine the genotype of a parent with a dominant trait?
Therefore, it is impossible to identify the genotype of an organism with a dominant trait by visually examining its phenotype. To identify whether an organism exhibiting a dominant trait is homozygous or heterozygous for a specific allele, a scientist can perform a test cross.
What must be present in order to express a dominant trait?
When a trait is dominant, only one allele is required for the trait to be observed. A dominant allele will mask a recessive allele, if present. A dominant allele is denoted by a capital letter (A versus a). Since each parent provides one allele, the possible combinations are: AA, Aa, and aa.
What are examples of dominant and recessive traits?
For example, having a straight hairline is recessive, while having a widow’s peak (a V-shaped hairline near the forehead) is dominant. Cleft chin, dimples, and freckles are similar examples; individuals with recessive alleles for a cleft chin, dimples, or freckles do not have these traits.
How do you tell if you have dominant genes?
If a person carries a heterozygous set of alleles (both uppercase and lower case letter of the gene) then the person will show the dominant trait (being that there is an uppercase letter present). For example, the brown eye allele is dominant, B.
Are blue eyes dominant or recessive?
Blue will always be recessive. If both parents have a blue allele, it is likely that the child will have blue eyes. However, if one parent has green eyes and the other blue, your child will most likely have green eyes, as green is dominant over blue.