Consider statements about photosynthesis: 1. Light reactions occur in the grana. 2. The Calvin cycle occurs in the stroma. 3. Oxygen is released from CO2. Which are correct? MCQ with Answer and Explanation

Explanation:
Differential centrifugation separates organelles by size and density by spinning homogenized cells at progressively higher speeds. Each pellet is enriched in a particular organelle. Density gradient centrifugation further refines separation. Electrophoresis separates by charge/size, chromatography by differential partitioning, spectrophotometry measures absorbance.

Explanation:
Apis cerana indica (the Indian honeybee) is the most commonly domesticated species for commercial apiculture (beekeeping) in India. It is well-adapted to the local climate and is less aggressive than Apis dorsata (the rock bee). Apis mellifera (the Italian bee) is also widely used globally and in India for its high honey yield and gentle nature. Apis florea is the little bee, which is not suitable for commercial beekeeping.

Explanation:
Cellulose, a linear polymer of β-D-glucose units linked by β-1,4-glycosidic bonds, forms microfibrils that provide tensile strength to plant cell walls. Glycogen is animal storage, starch plant storage, chitin in fungi and arthropods. Cellulose is the most abundant organic polymer on Earth.