Answer:
RNA is single-stranded and composed of nitrogenous bases, a phosphate group, and pentose sugar.
Explanation:
RNA is different from DNA because instead of having two matching bases; it is only made of one strand of nitrogenous bases. These bases are attached to the phosphate, which holds the whole strand of RNA together. The sugar acts as a carrier for the bases. The sugar in RNA is known as ribose and contains 5 carbon molecules. This is why it is called pentose sugar.
Answer:
The main difference between sieve tubes and companion cells is that sieve tubes are the long, narrow, pointed tubes present in the phloem of angiosperms whereas companion cells are attached to the sieve tubes, regulating the activity of sieve tubes.
<span>In the lock-and-key model of enzyme action, the "Substrate" fits into the "Active site" of the enzyme
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