The structure in the chloroplast that is the site of the light-dependent reactions is the: MCQ with Answer and Explanation

Explanation:
RNA contains uracil instead of thymine found in DNA. In DNA, adenine pairs with thymine; in RNA, adenine pairs with uracil. Adenine, guanine, and cytosine are common to both. Uracil is a pyrimidine base, structurally similar to thymine but lacking a methyl group. This distinction is used in genetic material identification and understanding transcription.

Explanation:
Vitamin C is a cofactor for the enzyme tyrosinase, which is involved in melanin synthesis. Vitamin A is for vision, B₆ for amino acid metabolism, D for calcium.

Explanation:
Agrobacterium tumefaciens is a soil bacterium that naturally transfers part of its Ti (tumor-inducing) plasmid DNA (T-DNA) into the plant genome, causing crown gall disease. Scientists have harnessed this capability by replacing the tumor-causing genes with desirable genes, making it a vector for creating transgenic plants. E. coli vectors are used for bacterial transformation.