Question

Caenorhabditis elegans has a genome size of 103Mb, how many number of genes (approx.) are there in its genome?

• A. 27,000
• B. 20,000
• C. 5800
• D. 4400

Hint:

Although C. elegans and humans have similar numbers of protein-coding genes (~20,000), human complexity is increased through alternative splicing and gene regulatory networks.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Caenorhabditis elegans is a small, free-living soil nematode widely studied as a model organism in developmental biology and genetics.
It was the first multicellular eukaryote to have its entire genome sequenced, completed in 199

Step 2: Detailed Explanation:
The genome of C. elegans consists of approximately 100 million base pairs (100 Mb) distributed across six chromosomes (five autosomes and one sex chromosome).
The sequencing project revealed that despite its simple anatomy, the nematode's genome contains a high density of genes.
It encodes approximately 20,000 protein-coding genes.
This gene count is surprisingly close to the number of protein-coding genes found in humans (approximately 20,000–25,000), illustrating that organismal complexity is not determined solely by the number of protein-coding genes.

Step 3: Final Answer:
The genome of Caenorhabditis elegans contains approximately 20,000 genes.