Protein Synthesis(DNA and RNA)

DNA

Deoxyribonucleic acid Located in the nucleus Double helix

Twisted ladder

DNA

Watson and Crick describe structure of DNA in 1953

The Nobel Prize in Physiology or Medicine 1962 was awarded jointly to Crick, Watson and Wilkins "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material".

Francis Crick James Watson

DNA

DNA Nucleotide Sugar - Deoxyribose Phosphate Base

Adenine – Thymine Guanine – Cytosine Mnemonic devices

A and T spell “AT” All Tigers Can Grow

DNA

Sides of ladder are consisted of sugars and phosphates

Rungs of ladder are consisted of nitrogen bases

DNA

Hydrogen bonds – holds bases together

DNA Replication

One strand of DNA “unzips” and make two strands of DNA by binding with free nucleotides

DNA Replication

RNA

Different types are used to translate instructions from DNA into making proteins

Ribonucleic acid Located in the cytoplasm

RNA

RNA Nucleotide Sugar - Ribose Phosphate Base

Adenine – Uracil Guanine – Cytosine

Mnemonic devices All Unicorns Can Grow

or

All Unibrows

Can Grow

U

Complementary Base Pairing

DNA A-T C-G

Examples of DNA replication: A-T-C-G-G-C-A-T-C

A-A-C-T-G-G-G-C-G

RNA A-U C-G

Examples of transcription: A-T-C-A-C-A-G-T-A

C-A-G-G-A-C-T-A-G

RNA

Three types of RNA Messenger RNA (mRNA)

Half of a ladder Ribosomal RNA (rRNA)

Hamburger bun shaped Transfer RNA (tRNA)

Attach to mRNA

mRNA

tRNA

rRNA

Codons

Codon – a sequence of three nucleotide bases that represents the “code” for one amino acid

Amino acid – a building block for proteins

Codons

Start codon - tells cells to begin making amino acids AUG

Stop codon – tell cells to cease amino acid production UAG UGA UAA

Transcription

The first stage in making amino acids

DNA is the blueprint for making amino acids

Transcription occurs in the nucleus

Transcription

DNA unzips and free ribonucleotides bind to the DNA strand

The finished product is a mRNA strand

mRNA leaves the nucleus and enters the cytoplasm

Translation

The second stage in producing amino acids

Translation occurs in the cytoplasm

A ribosome (or rRNA) attaches to a mRNA and scans the mRNA

Translation

One tRNA (or an anticodon) will attach to a codon to produce an amino acid

After an amino acid is formed, the tRNA will detach from the mRNA

Amimo acids are held together by peptide bonds

Two or more amino acids form a polypeptide

Progression of a protein Amino acid – the building blocks of proteins Polypeptide – two or more amino acids Protein – several polypeptide chains

Protein Synthesis Videos

http://www.youtube.com/watch?v=983lhh20rGY&feature=related

http://www.youtube.com/watch?v=41_Ne5mS2ls