The main function of tRNA is to
a. carry a message that, when translated, forms proteins
b. form a protein of ribosomes, a cell’s protein factories
c. string together complementary RNA and DNA strands
d. bring amino acids from the cytoplasm to the ribosomes
d. bring amino acids from the cytoplasm to the ribosomes
The main function of tRNA is to bring amino acids from the cytoplasm to the ribosomes.
To get the answer, we can analyze each option:
a. "carry a message that, when translated, forms proteins": This statement describes the function of mRNA, not tRNA. mRNA carries the genetic code from DNA and is responsible for protein synthesis.
b. "form a protein of ribosomes, a cell’s protein factories": This statement is incorrect. Ribosomes are composed of proteins and rRNA (ribosomal RNA), not tRNA.
c. "string together complementary RNA and DNA strands": This statement describes the function of RNA polymerase during transcription, not tRNA. RNA polymerase helps to produce mRNA by synthesizing an RNA strand complementary to a DNA template.
d. "bring amino acids from the cytoplasm to the ribosomes": This statement accurately describes the main function of tRNA. tRNA molecules have two important sites: an anticodon and an amino acid attachment site. The anticodon recognizes specific codons on the mRNA during translation, and the amino acid attachment site holds the appropriate amino acid. By binding to specific amino acids and recognizing their corresponding codons on the mRNA, tRNA ensures that the correct amino acids are brought to the ribosomes, where they are incorporated into growing polypeptide chains during protein synthesis.
Therefore, the correct answer is d. tRNA brings amino acids from the cytoplasm to the ribosomes.