Protein Synthesis

gene

A segment of DNA that holds the code for one polypeptide

4 nitrogen bases in DNA

Adenine, Guanine, Thymine, and Cytosine

triplet code

Code consists of three sequential bases (ex. GCC) that specifies the code for a particular amino acid

The Role of RNA

copies the DNA code in nucleus, then carries it into cytoplasm to ribosomes

2 differences of RNA and DNA

Uracil is replaced with thymine in RNA, and RNA has ribose instead of deoxyribose sugar

Three types of RNA:

Messenger RNA (mRNA), Ribosomal RNA (rRNA), and Transfer RNA (tRNA)

transcription

In the nucleus, code from DNA template strand is copied with complementary base pairs, resulting in a strand of mRNA

(DNA information coded in mRNA)

translation

In the cytoplasm, tRNA synthesis uses genetic information to produce proteins.

(mRNA decoded to assemble polypeptides)

3 phases of transcription

1. Initiation

2. Elongation

3. Termination

Initiation of transcription

RNA polymerase separates DNA strands

Elongation of transcription

RNA polymerase adds complementary nucleotides to growing mRNA.

Termination of transcription

Transcription stops at a termination signal code.