Which of the following is a defining feature of all chordates at some stage of their life? MCQ with Answer and Explanation

Explanation:
Simple diffusion is the passive movement of molecules (e.g., O₂, CO₂) from high to low concentration without the need for a membrane protein or energy. Osmosis specifically refers to water movement across a semipermeable membrane. Facilitated diffusion uses channel or carrier proteins but no energy. Active transport requires energy (ATP).

Explanation:
Photorespiration is a wasteful pathway that occurs when RuBisCO fixes O2 instead of CO2, producing phosphoglycolate. This 2-carbon compound is metabolized through a complex pathway involving three organelles: it is processed in the peroxisome, then the mitochondria, and finally returns to the chloroplast. This process consumes ATP and releases CO2 without producing any sugar.

Explanation:
R.H. Whittaker's five kingdom classification places all prokaryotic organisms in Kingdom Monera and unicellular eukaryotes in Kingdom Protista. Fungi are a distinct kingdom characterized by heterotrophic nutrition, primarily saprophytic or parasitic, and possess chitinous cell walls. They are not photosynthetic autotrophs. Therefore, statements 1 and 2 are correct, while 3 is incorrect.