The term 'tonoplast' refers to the membrane surrounding the: MCQ with Answer and Explanation

Explanation:
Monocots are less susceptible to Agrobacterium-mediated transformation using Ti plasmid. Therefore, direct gene transfer methods like particle bombardment (biolistics) are commonly used. The gene gun shoots DNA-coated gold or tungsten particles into plant cells. Ti plasmid works well for dicots. Bacteriophage and cosmids are for bacterial cloning.

Explanation:
Biological nitrogen fixation, performed by bacteria (Rhizobium, Azotobacter) and cyanobacteria, reduces N₂ to NH₃. Nitrification oxidizes ammonia to nitrates, denitrification returns N₂, ammonification releases ammonia from organic matter.

Explanation:
Pleiotropy occurs when one gene affects multiple seemingly unrelated traits. Example: phenylketonuria (PKU) affects mental development, skin pigmentation, and musty odor. Marfan syndrome affects skeleton, eyes, and heart. Polygenic is many genes affecting one trait, epistasis is gene interaction, codominance is both alleles expressed.