Question

The fruit fly Drosophila melanogaster was found to be very suitable for experimental verification of chromosomal theory of inheritance by Morgan and his colleagues because :

• A. it reproduces parthenogenetically
• B. a single mating produces two young flies
• C. smaller female is easily recognisable from larger male
• D. it completes life cycle in about two weeks

Answer 1

The Correct Option is D

The fruit fly, Drosophila melanogaster, is an important organism in genetics research and was particularly crucial in the experimental verification of the chromosomal theory of inheritance by Morgan and his colleagues. Let's explore why it was chosen for these studies and analyze the given options to determine the correct answer.

1. Option: It reproduces parthenogenetically

   Parthenogenesis is a form of asexual reproduction where an egg can develop into an individual without fertilization. Drosophila melanogaster does not typically reproduce parthenogenetically. Therefore, this option is incorrect.

2. Option: A single mating produces two young flies

   This option is factually incorrect as Drosophila melanogaster produces many offspring from a single mating, contributing to their suitability for genetic studies due to the larger pool of progeny. This characteristic makes them ideal for observing inheritance patterns over generations. Hence, this option is incorrect.

3. Option: Smaller female is easily recognisable from larger male

   While there are distinguishable physical differences between male and female fruit flies, this specific feature was not a primary reason for their selection in genetic studies, particularly those conducted by Morgan. This option is incorrect.

4. Option: It completes life cycle in about two weeks

   This option is correct. One of the most significant advantages of using Drosophila melanogaster in genetic research is their short life cycle. They typically complete their life cycle in about two weeks, which facilitates rapid generational studies, enabling researchers to observe genetic variations and inheritance patterns quickly.

Therefore, the reason Drosophila melanogaster was found suitable for verifying the chromosomal theory of inheritance is that it completes its life cycle in about two weeks, allowing for efficient and detailed genetic analysis.