Protein Synthesis

Protein Synthesis

Remember: DNA Replication

How does DNA makeall of our characteristics?

Genes make proteins…

Nucleic Acids

• To make proteins, we need both types of nucleic acids: DNA and RNA

Deoxyribonucleic Acid Ribonucleic Acid

Nucleic Acids

DNA RNA

Sugar Deoxyribose Ribose

Bases A C G T A C G U

Strand Double Single

Wherever DNA has the base thymine, RNA has the base uracil.

3 Typesof RNA

• Messenger–mRNA

• Transfer– tRNA

• Ribosomal– rRNA

Protein Synthesis• The process of reading DNA to make proteins is

called protein synthesis.

The Central Dogma of Genetics says that genetic information goes

from DNA RNA Protein.

The steps of the Central Dogma are: 1. DNA Transcription

2. RNA Translation3. Protein Folding.

Step 1: Transcription

An mRNA strand is formed from

the DNA.

Just like in DNA Replication, helicase

unzips the DNA and RNA Polymerase builds the

new mRNA strand.

Three letters in a row on the mRNA is called a codon. The matching three

letters on tRNA is called an anticodon.

Step 2: TranslationRibosomes read the mRNA.

A tRNA molecule with the right anticodon matches up to the mRNA codon and attaches the correct

amino acids to the chain.

Protein Folding

Once the amino acid chain is complete, it leaves the ribosome and goes through the Rough ER and the Golgi Apparatus to be folded in to its protein shape.

Check Your Understanding1. How is RNA different from DNA?

2. What does the Central Dogma of Genetics say?

3. What are the two steps of Protein Synthesis and what happens in each step?

RNA is a single strand, has ribose sugar instead of deoxyribose, and uses the base

uracil instead of thymine.

DNA RNA Protein

1. Transcription – DNA is transcribed (copied) into mRNA2. Translation – mRNA is translated into an amino acid chain