chapter 9 part A part 1

Mature messenger RNA (mRNA)

The template for protein synthesis that has been processed in the nucleus.

Capping

The addition of a methylated cap at the 5' end of mRNA during processing.

Splicing

The process of removing introns and joining exons in mRNA to generate the open reading frame.

Poly-adenylation

The addition of a poly-A tail at the 3' end of mRNA during processing.

Ribonucleoproteins (RNPs)

Proteins that coat mRNA and play roles in its processing, transport, and stability.

Ribosomes

Large complexes of RNA and proteins that serve as the translation machinery in protein synthesis.

Eukaryotic ribosomes

Ribosomes found in eukaryotic cells, composed of a large (60S) and a small (40S) subunit.

70S ribosomes

Ribosomes found in prokaryotic organisms, consisting of a large and a small subunit.

Amino acids

The building blocks of proteins carried by transfer RNAs (tRNAs) during translation.

Transfer RNAs (tRNAs)

Small RNA molecules that transport specific amino acids to the ribosome during translation.

Cloverleaf structure

A 2D representation of tRNA that features an anticodon loop and an acceptor stem.

Anticodon loop

The part of tRNA that reads the mRNA codon during translation.

Acceptor stem

The portion of tRNA responsible for carrying the attached amino acid.

Aminoacyl-tRNA complexes

Formed by tRNAs binding to their corresponding amino acids via aminoacyl-tRNA synthetases.

Aminoacyl-tRNA synthetases

Enzymes that match amino acids to the proper tRNAs during protein synthesis.

Genetic Code

The set of rules by which information encoded in genetic material (DNA or RNA sequences) is translated into proteins (amino acid sequences) by living cells.

Codon

A sequence of three nucleotides in an mRNA molecule that specifies a particular amino acid or signals termination during protein synthesis.

Start Codon

The first codon in an mRNA transcript that indicates where protein synthesis should begin, typically AUG, which codes for methionine.

Stop Codon

A three-nucleotide sequence in mRNA that signals the termination of protein synthesis. Examples include UAA, UAG, and UGA.

Peptide bond

The covalent chemical bond formed between the carboxyl group of one amino acid and the amino group of another during protein synthesis, linking them into a polypeptide chain.