The phenomenon where a single gene mutation affects multiple traits is: MCQ with Answer and Explanation

Explanation:
Ex-situ (off-site) conservation involves protecting endangered species outside their natural habitats. Zoological parks, botanical gardens, seed banks, and cryopreservation facilities are examples of ex-situ conservation. This method allows for controlled breeding, research, and education, and can be a last resort for species whose natural habitats are severely degraded or destroyed.

Explanation:
Nostoc is a cyanobacterium (blue-green alga) that fixes atmospheric nitrogen and is used as a biofertilizer in rice paddies. Anabaena azollae with Azolla is also common. Rhizobium is bacterial biofertilizer for legumes, Azospirillum is a free-living nitrogen-fixing bacterium. Trichoderma is a fungal biocontrol agent. BGA biofertilizers increase organic nitrogen in soil.

Explanation:
Phototropism (positive in shoots) is caused by the migration of auxin to the shaded side of the shoot, promoting cell elongation more on that side, causing the shoot to bend towards light. This asymmetric auxin distribution was demonstrated by Went's experiments. Auxin is sensitive to light and moves laterally. This is a growth response to directional light.