AP BIOLOGY

Detailed explanation-1: -Three main types of RNA are involved in protein synthesis. They are messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). rRNA forms ribosomes, which are essential in protein synthesis. A ribosome contains a large and small ribosomal subunit.

Detailed explanation-2: -Molecules of rRNA are synthesized in a specialized region of the cell nucleus called the nucleolus, which appears as a dense area within the nucleus and contains the genes that encode rRNA. The encoded rRNAs differ in size, being distinguished as either large or small.

Detailed explanation-3: -Within the ribosome, the rRNA molecules direct the catalytic steps of protein synthesis-the stitching together of amino acids to make a protein molecule. In fact, rRNA is sometimes called a ribozyme or catalytic RNA to reflect this function.

Detailed explanation-4: -Transfer RNA (tRNA) is found in the cytoplasm and has a complex shape. It is responsible for carrying amino acids from the cytoplasm to the ribosome surface, ready to make a protein as instructed by the mRNA.

Detailed explanation-5: -Transfer RNA (abbreviated tRNA) is a small RNA molecule that plays a key role in protein synthesis. Transfer RNA serves as a link (or adaptor) between the messenger RNA (mRNA) molecule and the growing chain of amino acids that make up a protein.