AIM:How are amino acids formed into proteins?PEPTIDE BOND:

Joins Two AMINO ACIDS together

JANUARY 16th, 2009

How does DNA get into every cell? -DNA Replication is when DNA makes a copy of itself.

-DNA Replication is important because cells need DNA to make proteins they need to survive.

-When DNA replicates it produces two DNA molecules that are identical (exactly the same) as the original parent strand:

Picture of DNA Replication:

1 DNA 2 DNA

DNA Replication

Practice with DNA Replication -Let’s practice DNA replication! I’ll give you one strand

of DNA, and you complete the complementary strand of DNA. (Remember, A=T, G=C)

Original Strand: ATTAGGCTATTGACGATAGCCATGGA

Complementary Strand: TAATCCG

Practice with DNA Replication -Let’s practice DNA replication! I’ll give you one strand

of DNA, and you complete the complementary strand of DNA. (Remember, A=T, G=C)

Original Strand: ATTAGGCTATTGACGATAGCCATGGA

Complementary Strand: TAATCCGATAACTGCTATCGGTACCT

Practice with DNA Replication Original Strand: GCCATAGGATTTATATGGCATAT

Complementary Strand:

Practice with DNA Replication Original Strand: GCCATAGGATTTATATGGCATAT

Complementary Strand: CGGTATCCTAAATATACCGTATA

R _ _ _ _ _ _ _ _ _N:Making an exact copy of DNA

D. How does the cell use DNA to make proteins? -DNA is used as directions for making

proteins. -DNA cannot leave the nucleus, so in order to

make proteins, RNA must be made. -RNA is much like DNA however it only has

one strand and instead of using the nucleotide Thymine (T) it uses the nucleotide Uracil (U). (A=U)

-RNA uses the sugar ribose while DNA uses the sugar deoxyribose.

DNA BothRNA double stranded A=T uses the sugar

deoxyribose cannot leave the

nucleus used in DNA

Replication

single stranded A=U uses the sugar

ribose Can leave the

nucleus used in

translation

-both are used in transcription

-made up of phosphates, sugars and nitrogen bases

-contain genetic information

-use G, C and A

-Our bodies need proteins in order to operate correctly. There are two cellular processes in charge of making proteins:

1. Transcription: DNA is made into mRNA. This happens in the nucleus. (DNARNA)

Picture of Transcription:

1 DNA 1 mRNA

Transcription

Transcription Video

Practice with Transcription

-Let’s practice transcription! I’ll give you one strand of DNA, and you complete the complementary strand of RNA. (Remember, in RNA replace T with U).

DNA strand: ATTAGGCCGGATTAGCCTATTA RNA strand: UAAUCCG

DNA strand: ATTGCATTATCGATTATCCTAT RNA strand:

Practice with Transcription

-Let’s practice transcription! I’ll give you one strand of DNA, and you complete the complementary strand of RNA. (Remember, in RNA replace T with U).

DNA strand: ATTAGGCCGGATTAGCCTATTA RNA strand:UAAUCCGGCCUAAUCGGAUAAU

DNA strand: A TTGCAT TATCGAT TATCCTAT RNA strand: UAACGUAAUAGCUAAUAGGAUA

After transcription, mRNA leaves the nucleus and attaches to the ribosomes where translation begins.

2. Translation: mRNA is turned into amino acids which fold to make proteins. This happens on the ribosome. (mRNA amino acids)

Picture of Translation:

1 mRNA

Translation

Amino Acid chain

-In order to make the amino acid chain in translation, the mRNA is “read” with each set of three nucleotides acting like a word.

-Each of these 3 letter words is called a codon, and different codons code for different amino acids.

Ex: AUG=amino acid methionine GCA=amino acid alanine

(3 nucleotides=1 codon=1 amino acid)

-You can use a chart to figure out what 3 nucleotides code for each of the 20 amino acids that make up proteins:

Translation Practice

-Let’s practice translation! I’ll give you the mRNA strand, and you figure out what amino acids it codes for. (Remember, 3 nucleotides=1 amino acid)

mRNA strand: AUG CCC UUU GAG AAG CGU UAA

amino acid chain: methionine-histidine

mRNA strand: AUG GGG UGG AGA AGU GUG UGA

amino acid chain:

mRNA strand: AUGAGUAACCCAUAA

amino acid chain:

Translation Practice

-Let’s practice translation! I’ll give you the mRNA strand, and you figure out what amino acids it codes for. (Remember, 3 nucleotides=1 amino acid)

mRNA strand: AUG CCC UUU GAG AAG CGU UAA

amino acid chain: methionine–histidine–phenylalanine–glutamate–lysine-arginine-stop

mRNA strand: AUG GGG UGG AGA AGU GUG UGA

amino acid chain:

mRNA strand: AUGAGUAACCCAUAA

amino acid chain:

Translation Practice

-Let’s practice translation! I’ll give you the mRNA strand, and you figure out what amino acids it codes for. (Remember, 3 nucleotides=1 amino acid)

mRNA strand: AUG CCC UUU GAG AAG CGU UAA

amino acid chain: methionine–histidine–phenylalanine–glutamate–lysine-arginine-stop

mRNA strand: AUG GGG UGG AGA AGU GUG UGA

amino acid chain: methionine-glycine-tryptophan-SERINE-valine-stop

mRNA strand: AUG AGU AAC CCA UAA

amino acid chain: met ser asp pro stop

Translation Video

-There are 3 types of RNA used in making proteins:

-what ribosomes are made up of; it gives the mRNA a place to attach to during translation

Ribosomal RNA (rRNA)

-brings amino acids to the ribosome during translation to help make the amino acid chain

Transfer RNA (tRNA)

-carries information found in DNA out of the nucleus so that proteins can be made (used in transcription and translation)

Messenger RNA (mRNA)

Picture of itWhat it doesName

Ribosome

I don’t care what you heard about me

But my RNA can make all of my proteins

All my As and Us and Cs and Gs

My RNA is coding for Proteins!