Chapter Nine 

A ribosome is an intercellular structure made of both RNA and protein,

What is RNA?

Unlike DNA RNA has a single strand instead of a double helix. The main function of RNA is to create proteins via translation. RNA carries genetic information that is translated by ribosomes

The steps of translation are initiation,

in which initial recognition of promoter DNA

RNAP triggers a series of conformational changes in both RNAP and promoter DNA.

What is RNAP?

multisubunit enzyme that transcribes template DNA into RNA

What is promoter DNA?

a region of DNA where relevant proteins such as RNA polymerase

 a multi-unit enzyme that synthesizes RNA molecules from a template of DNA through a process called transcription

and transcription factors bind to initiate transcription of that gene

the process by which a cell makes an RNA copy of a piece of DNA

elongation,

the addition of nucleotide units, resulting in the lengthening of the nucleic acid chain.

nucleotide units being ribose in RNA or attached to a phosphate group and a nitrogen-containing base.

and termination

the ending of transcription, and occurs when RNA polymerase crosses a stop (termination) sequence in the gene

and it is the site of protein synthesis

What are proteins?

Proteins are biopolymeric structures composed of amino acids

biopolymers consist of monomeric units that are covalently bonded in chains to form larger molecules

What is protein synthesis?

Protein synthesis is the process in which cells make proteins. It occurs in two stages: transcription and translation

The ribosome reads the messenger RNA (mRNA) sequence

Messenger RNA (mRNA) molecules carry the coding sequences for protein synthesis and are called transcripts

and translates that genetic code into a specified string of amino acids,

which grow into long chains that fold to form proteins

each ribosome consists of two separate RNA-protein complexes, known as the small and large subunits. 

the smaller of the two major RNA components of the ribosome. Associated with a number of ribosomal proteins

Large RNA is responsible for the catalysis of peptide bond formation, an enzymatic activity that covalently links amino acids

The large subunit sits on top of the small subunit, with an RNA template between the two

One of the two strands of the DNA double helixthen acts as a template for the synthesis of an RNA molecule