Answer:
The mRNA (messenger RNA) carries the info regarding what protein is to be made. ... The tRNA (transport RNA) carries the amino acid to the rRNA. The rRNA (ribosomal RNA) makes up the ribosome. The ribosome builds the protein according to the instructions written in the mRNA with the amino acids ferried in by the tRNA
The three common parts of a nucleotide are a nitrogen base, a phosphate group, and a pentose sugar.
C. They are not enclosed by a membrane.
D is incorrect because Ribosomes do not contain DNA, the nucleolus does.
B is also incorrect because they aren't located outside the cell, they're in the cell, on the endoplasmic reticulum.
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