Is DNA living?Is DNA living?

In genetics we talked about how In genetics we talked about how parents pass their genes onto their parents pass their genes onto their offspring. How do these genes (made offspring. How do these genes (made of DNA) turn into things like hair color, of DNA) turn into things like hair color, eye color or genetic disorders?eye color or genetic disorders?

Answer: Answer: Protein SynthesisProtein Synthesis

RNA

Proteins

DNATranscription

Translation

RNARNA (ribonucleic acid) (ribonucleic acid)

Difference between RNA and DNADifference between RNA and DNA Ribose instead of deoxyriboseRibose instead of deoxyribose Uracil instead of thymine (U bonds to Uracil instead of thymine (U bonds to

A)A) Single strandedSingle stranded Types of RNATypes of RNA Messenger RNAMessenger RNA ( (mRNAmRNA) – transfers ) – transfers

information from DNA to ribosome. information from DNA to ribosome. Contains the codons.Contains the codons.

Transfer RNATransfer RNA ( (tRNAtRNA) – made of an ) – made of an anticodon and amino acid. There are anticodon and amino acid. There are only 20 amino acids but many tRNAsonly 20 amino acids but many tRNAs

Part 1 of Protein Synthesis: Part 1 of Protein Synthesis: TranscriptionTranscription

-synthesis of mRNA--synthesis of mRNA-

1.1. Only Only 11 strand of DNA is strand of DNA is transcribed – RNA polymerase transcribed – RNA polymerase determines where to determines where to startstart by by finding “promotor” base finding “promotor” base sequence on the DNA (sequence on the DNA (TACTAC))

2.2. TerminationTermination is controlled by a is controlled by a Stop sequence Stop sequence

CodonsCodons

CodonCodon – a group of 3 bases on – a group of 3 bases on mRNA that codes for an amino mRNA that codes for an amino acid. Example: UUAacid. Example: UUA

Take a closer look at this Take a closer look at this processprocess

http://www.youtube.com/watch?http://www.youtube.com/watch?v=D3fOXt4MrOM&feature=relatedv=D3fOXt4MrOM&feature=related

AnticodonsAnticodons

AnticodonAnticodon – group of 3 bases on – group of 3 bases on a tRNA that is complementary to a tRNA that is complementary to the codon. Example AAUthe codon. Example AAU

Part 2 of Protein Synthesis: Part 2 of Protein Synthesis: TranslationTranslation

1.1. mRNA is held in place by the mRNA is held in place by the ribosome.ribosome.

2.2. tRNAs with the anticodon and tRNAs with the anticodon and amino acid temporarily bond to amino acid temporarily bond to the complimentary codon of the the complimentary codon of the mRNAmRNA

3.3. The tRNAs carry the amino acid.The tRNAs carry the amino acid.4.4. The amino acids attach to each The amino acids attach to each

other making the protein.other making the protein.

For the following DNA strand For the following DNA strand determine the mRNA, tRNAs determine the mRNA, tRNAs and the protein.and the protein.

gggtacagtcggtagtggattgccgggtacagtcggtagtggattgcc

cccatgtcagccatcacctaacggcccatgtcagccatcacctaacgg

ggggggtacagtcggtagtggatttacagtcggtagtggattgccgcc

mRNAmRNAaugucagccaucaccuaaaugucagccaucaccuaa

tRNA tRNA uac agu cgg uag ugg auuuac agu cgg uag ugg auu

Protein: Start-Serine-Alanine-isolucine-threonine-Stop

For the following DNA strand For the following DNA strand determine the mRNA, tRNAs determine the mRNA, tRNAs and the protein.and the protein.

ccctacatattacgagaacacgtaactccccctacatattacgagaacacgtaactcc