In the Roundworm C

question 13

Multiple Choice

In the roundworm C. elegans, the lin- 4 gene produces an RNA that forms a hairpin structure. One of the strands in the double- stranded region of lin- 4 hairpin RNA is complementary to the mRNA of a protein- coding gene, lin- 14. Predict the effect of expressing lin- 4 RNA during development.

• A) The lin- 14 expression will rise when lin- 4 expression begins.
• B) The lin- 4 RNA will bind the promoter of the lin- 14 gene, destroying the lin- 14 gene.
• C) The lin- 4 RNA will bind to the enhancer of lin- 14, increasing lin- 14 transcription.
• D) The lin- 14 expression will fall when lin- 4 expression begins.

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Definitions:

Book Lungs

Respiratory organs found in certain arachnids, such as spiders and scorpions, consisting of stacked leaf-like structures used for gas exchange.

Malpighian Tubules

Excretory structures in insects and some arthropods that remove metabolic wastes from the body into the digestive tract for excretion.

Tympanum

The eardrum, a thin membrane that vibrates in response to sound waves, playing a key role in the hearing process.

Cephalothorax

The fused head and thorax found in certain arthropods, such as spiders and crustaceans, which houses both sensory and motor organs.