The vitamin that prevents neural tube defects during fetal development is: MCQ with Answer and Explanation

Explanation:
The loop of Henle, especially the descending limb (permeable to water) and ascending limb (impermeable, active salt transport), creates an osmotic gradient in the medulla. This countercurrent multiplier system enables the kidney to produce concentrated or dilute urine depending on hydration status. ADH acts on the collecting duct to utilize this gradient.

Explanation:
In the biogeochemical carbon cycle, carbon dioxide (CO2) is removed from the atmosphere primarily by autotrophs (plants, algae) through the process of photosynthesis, where it is fixed into organic compounds (glucose). Carbon is returned to the atmosphere through respiration (by plants and animals), decomposition of dead organic matter, and combustion of fossil fuels.

Explanation:
Messenger RNA (mRNA) is transcribed from DNA and carries the codon sequence to ribosomes, where it is translated into a polypeptide. tRNA brings amino acids, rRNA forms ribosomal structure, snRNA involved in splicing.