Products of Transcription

Know the major classes of RNA molecules.

The three major types of RNA are mRNA, tRNA and rRNA. I've probably spoken about them before but I honestly reckon it'll be less effort for me to write it out again than go back and find a previous post about it. mRNA, or "messenger RNA," carry a transcript that will later be translated into a protein. tRNA carry amino acids to the ribosomes where mRNA is being translated. rRNA form parts of ribosomes, along with ribosomal proteins.

Know the differences between prokaryotic and eukaryotic mRNA.

I covered this in my previous post about the mechanism of transcription.

Know the structure and function of tRNA and function of aminoacyl-tRNA synthetases.

I covered this in a previous post about peptide bonds between amino acids. There is a different aminoacyl-tRNA synthetase for every amino acid, all named for the amino acid that they attach: for example, leucyl-tRNA synthetase attaches leucine to tRNA. As mentioned in the post that I just linked to, ATP is required for this process.

Know the differences between prokaryotic and eukaryotic ribosomes.

The main difference between prokaryotic and eukaryotic ribosomes is that eukaryotic ribosomes are larger.

Eukaryotic ribosomes are 80S, with a large 60S subunit and a small 40S subunit. The large subunit contains 5S, 5.8S and 28S rRNA whereas the small subunit contains 18S rRNA. (The S refers to the sedimentation coefficient or something. I'm not really sure how it's measured.)

Prokaryotic ribosomes, on the other hand, are 70S, with a large 50S subunit and a small 30S subunit. The large subunit contains 5S and 23S rRNA whereas the small subunit contains 16S rRNA.

Know the roles of ribosome binding sites in translation of mRNA to protein.

There are three binding sites in the ribosome: the A (aminoacyl) site, the P (peptidyl) site and the E (exit) site. The A site is where an aminoacyl-tRNA will initially enter the ribosome. After being added to the polypeptide chain, it will move across to the P site, and eventually along to the E site, where it exits the ribosome.

Know the definitions of polycistronic mRNA, polyribosome, mRNA cap, poly-A tail, codon, anticodon, amino acyl tRNA.

Polycistronic mRNA- mRNA that codes for multiple different proteins at the same time.
Polyribosome- Several ribosomes working to translate the same mRNA at the same time.
mRNA cap- A 7-methylguanosine "cap" that is attached to the 5' end of mRNA during eukaryotic mRNA processing. If I understood correctly, it's the place where the ribosomes bind onto the mRNA. The mRNA cap also provides some protection from early degradation.
Poly-A tail- A long series of A bases at the 3' end of mRNA. Also serves to protect against early degradation.
Codon- A series of three bases on the mRNA that code for either an amino acid or a stop codon.
Anticodon- A series of three bases on the tRNA that bind to a codon on the mRNA.
Aminoacyl-tRNA- tRNA with an amino acid attached at the 3' end.