In a dihybrid cross, the F₂ phenotypic ratio is: MCQ with Answer and Explanation

Explanation:
Mitochondria have circular DNA and 70S ribosomes, enabling them to transcribe and translate some proteins independently, hence semi-autonomous. They still depend on nuclear genes for most proteins. The reason correctly explains the assertion.

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:
Monocots typically have trimerous flowers (floral parts in multiples of three), parallel venation, fibrous roots, and one cotyledon. Dicots have reticulate venation, taproots, tetramerous/pentamerous flowers, and two cotyledons. Examples: grasses, lilies, orchids. These features are key in plant classification.