Which tissue is responsible for the increase in the girth of a dicot stem? MCQ with Answer and Explanation

Explanation:
The counter-current mechanism involves the Loop of Henle and the vasa recta (blood capillaries surrounding the loop). The flow of filtrate in the two limbs of the Loop of Henle is in opposite directions, and the flow of blood in the two limbs of vasa recta is also counter-current. This mechanism helps maintain a high osmolarity gradient in the medullary interstitium, essential for concentrating urine.

Explanation:
The spliceosome is a large, dynamic complex composed of five small nuclear ribonucleoproteins (snRNPs, pronounced 'snurps') and numerous other protein factors. It assembles on the pre-mRNA transcript in the nucleus. Its primary function is to catalyze the splicing of pre-mRNA: it precisely recognizes the splice sites at the boundaries of introns and exons, removes the non-coding intron sequences, and ligates (joins) the coding exons together to form a continuous, mature mRNA molecule that can be exported to the cytoplasm for translation.

Explanation:
Recombinant human insulin (Humulin) is produced by genetically engineered Escherichia coli (or yeast) carrying the human insulin gene. Before this, insulin from animal sources was used. The A and B chains of insulin are produced separately and then combined. This was the first genetically engineered pharmaceutical approved for human use (1982).