Question

Select the incorrect match :

• A. Polytene chromosomes - Oocytes of amphibians
• B. Lampbrush chromosomes - Diplotene bivalents
• C. Submetacentric chromosomes - L-shaped chromososmes
• D. Allosomes - Sex chromosomes

Answer 1

The Correct Option is A

To determine the incorrect match from the given options, let's analyze each option with the relevant biological concepts.

1. Polytene chromosomes - Oocytes of amphibians: Polytene chromosomes are oversized chromosomes found in the salivary glands of Drosophila (fruit flies) and some other dipteran insects. They are not typically associated with the oocytes of amphibians. Instead, amphibian oocytes are more likely to contain lampbrush chromosomes. Therefore, this is the incorrect match.
2. Lampbrush chromosomes - Diplotene bivalents: Lampbrush chromosomes are a special type of chromosome found in the oocyte nuclei of most vertebrates, including amphibians, during the diplotene stage of meiosis. They are indeed characterized as being in the diplotene bivalents stage. Thus, this match is correct.
3. Submetacentric chromosomes - L-shaped chromosomes: Submetacentric chromosomes have their centromere located slightly off-center, resulting in one arm being longer than the other. They are often described as being L-shaped due to this asymmetry. Hence, this match is correct.
4. Allosomes - Sex chromosomes: Allosomes are indeed sex chromosomes. They differ from autosomes, which are non-sex chromosomes. Therefore, this match is correct.

In conclusion, the incorrect match is Polytene chromosomes - Oocytes of amphibians since polytene chromosomes are not associated with amphibian oocytes but with certain insect species' salivary glands.