Answer:
D.
Explanation:
An allele that expresses itself even in the presence of an alternative allele is known as a dominant allele. An allele that is not expressed in the presence of an alternative allele is called a recessive allele.
Mendel's Law of Inheritance
- Law of dominance- It is the first law of Mendel.- It states that in a cross between two organisms that are pure for any pair of contrasting characters, the character that expresses in the first generation is dominant and the one which is suppressed is recessive.
- Law of segregation- It is the second law of Mendel. It states that members of allelic pairs in a hybrid remain together without mixing with each other and they segregate during gamete formation
In fruit flies, the allele for long wings (L) is dominant and the allele for short wing (l) is recessive. The likely genotype of the fruit fly with short wings is only ll.
A. Either LL or Ll- According to the law of dominance allele L will be dominant over allele l. Hence the fruit fly with genotype LL or Ll will have long wings.
B. Either Ll or ll- According to the law of dominance allele L will be dominant over allele l. Hence the fruit fly with genotype Ll will have long wings. The recessive allele is expressed only in the absence of other alleles. The allele for short wing (l) is recessive and is present in homozygous condition, There is an absence of another allele Hence the genotype of the fruit fly with short wing will be ll.
C. Only LL- According to the law of dominance allele L will be dominant over allele l. Hence the fruit fly with genotype LL will have long wings.
D. Only ll- The recessive allele is expressed only in the absence of other alleles. The allele for short wing (l) is recessive and is present in homozygous condition, There is an absence of another allele.
Hence the genotype of the fruit fly with short wing will be (D.) only ll.
