lipids

carbohydrates

proteins

nucleic acids

EnzymesEnzymes are are proteins which proteins which

function to function to control the rate control the rate

of chemical of chemical reactions.reactions.

complex organic compounds made up of amino acids,

needed for the body to function properly

examples: examples: muscles, hair, muscles, hair, cartilage, nailscartilage, nails

contain C, O, H, contain C, O, H, N N and usually Sand usually S

image credit: U.S. Department of Energy Human Genome Program, http://www.ornl.gov/TechResources/Human_Genome/graphics/slides/images/ras.gif

3D protein structure

anan aminoamino groupgroup

are made up of

and an “and an “RR” group ” group which varies in the which varies in the

different amino different amino acidsacids

a a carboxylcarboxyl group groupH

HN C

H

R

O

OHC

CH

H H

H

HN C

H O

OHC

COH

H H

H

HN C

H O

OHC

Alanine Serine

What is the name of these monomers?

To what organic compound group do they belong?

N

H

H

H

O

R

C C

O

H

N

H

H

H

O

R

C C

O

H

amine group

variable R group

carboxyl group

carboxyl groupamine group

What does the chain of amino acids represent?

Threonine

Arginine

GlycineGlycine

Proline

Asparagine

Proline Alanine

Polypeptide Chain – A Protein

What is the monomer (subunit) for protein?

What are the functions of protein?

Name examples of proteins.

amino acids

structure or support; enzymes speed up chemical reactions

muscles, hair, cartilage, nails

TRY THIS!Create a concept map using the 4 organic compounds.

Include: monomer, functions and examples.

Protein Synthesis VocabularyProtein Synthesis is when DNA’s code is used by the cell to make proteins. Protein Synthesis is also called gene expression.The genes “express themselves” when the proteins they code for are made.VOCABULARY:GENECODONAMINO ACID

Protein Synthesis VocabularyProtein Synthesis is when DNA’s code is used by the cell to make proteins. Protein Synthesis is also called gene expression.The genes “express themselves” when the proteins they code for are made.VOCABULARY:GENECODONAMINO ACID

Gene ExpressionGENE: sequence of DNA that codes for a protein and thus determines a traitCODON: nucleotide triplet that codes for a specific amino acidAMINO ACIDS: amino acids make up proteinsACG

GGAGGC

CCA

AAC

CCG

GCCCGC

Threonine

Arginine

GlycineGlycine

Proline

Asparagine

Proline

Alanine

Amino Acid

protein

Chromosome

DNA

Gene

Sections within a gene

CODONS

TACCodes for protein

Codon base triplets

Examples ATC CCG

Stop Codon Start Codon

ATT, ATC, or ACT

Codons, Amino Acid & ProteinOne codon codes for one amino acid

EX: ACG = amino acid (threonine)CGC = amino acid (arginine)GGA = aminio acid (glycine)

A sequence of amino acids is a protein

ACG

GGAGGC

CCA

AAC

CCG

GCCCGC

Threonine

Arginine

GlycineGlycine

Proline

Asparagine

Proline

Alanine

Amino Acid

Protein

DNA has the code but RNA is needed to make proteins.

There are major differences between DNA and RNA….

DNA vs RNAContains deoxyribose sugarIs double strandedBonds A-T and C-GNever leaves the nucleus

Contains ribose sugarIs single strandedBonds A-U and C-GCan leave the nucleus

How Does RNA Help?DNA - contains the master code

tRNA towing

Amino acid

mRNA

Proteinfactory

tRNA, transfer RNAcarries amino acids

rRNA, ribosomal RNAguides the process in the

ribosome

mRNA, messenger RNAcopies/carries the DNA code

How Does RNA Help?DNA - contains the master code

tRNA towing

Amino acid

mRNA

Proteinfactory

tRNA, transfer RNAcarries amino acids

rRNA, ribosomal RNAguides the process in the

ribosome

mRNA, messenger RNAcopies/carries the DNA code

Chromosome DNA

The Role of ENZYMES

To what organic compound group do enzymes belong?

Enzymes are necessary in making a protein by controlling different parts of the reactions.breaks hydrogen bonds between nitrogen basesbrings new nucleotides and bonds them to existing strands

TranslationProtein is made by mRNA and tRNAInformation is “deciphered” to build a protein.

TranscriptionmRNA is made by copying DNA’s code for a proteinInformation in DNA is “rewritten” as a molecule of mRNA

DNADNA contains the code for all traits/ proteins

Overall Process of Protein Synthesis (Gene Expression)

DNA

Transcription Translation

mRNAProtein

TRANSCRIPTION

TRANSCRIPTION: mRNA is made copying DNA’s code

Uses enzymes

Makes mRNA from DNA template

Occurs in the nucleus

click to play animation

A

T

T

C

C

G

TRANSCRIPTION1. Enzymes help a gene portion of the DNA to unzip.enzymes break the bonds between the nitrogen bases

A

A

G

G

C

T

T

C

C

A

A

T

A

G

G

C

G

TRANSCRIPTION1. (continued) a gene portion of the DNA strand separates

A

T

A

G

G

C

A

T

T

C

C

G

2. mRNA is made from the DNA template

Enzymes bring in mRNA nucleotides and matches them with their DNA complement

A

T

A

G

G

C

A

T

T

C

C

G

TRANSCRIPTION

Base Pairing Rule

mRNA nucleotides match by the base pairing rule.

A - T (RNA has U)C - G

T

G

G

C

A

A

A

T

T

C

C

G

G

A

C

G

A

U

A

T

A

G

G

C

T

A

T

C

C

G

A

G

A

TT

A

T

A

G

G

C

A

T

T

C

C

G

G

A

C

G

A

U

mRNADNA

A

T

A

G

G

C

G

A

G

A

U

3. mRNA separates from DNA and leaves the nucleus

A

T

T

C

C

G

C

A

T

A

G

G

C

A

T

T

C

C

G

G

A

C

G

A

U

A

T

A

G

G

C

A

T

T

C

C

G

4. The two DNA strands move back together

A

T

A

G

G

C

A

T

A

G

G

C

A

T

T

C

C

G

A

T

T

C

C

G

4. An enzyme helps the DNA strands rezip.

REVIEWING TRANSCRIPTIONTRANSCRIPTION: mRNA is made copying DNA’s code

1. DNA unzips2. mRNA is made from the DNA template3. mRNA separates from DNA and leaves the nucleus4. The DNA molecule rezips (closes back up.)

click to play animation

TRY THIS!

Transcribe this segment of DNA:

CATAACCGATGA

DNA: CATAACCGATGAmRNA: GUAUUGGCUACU

ANSWER

TRANSLATIONProcess when the protein is actually made

• Uses an anticodon to the tRNA to bring an amino acid to the ribosome

• Occurs at the ribosome in the cytoplasm

click to play animation

5. mRna leaves the nucleus and travels to the ribosome in the cytoplasm

And Auld Lang Syne!REMEMBER:DNA’s code is copied to mRNA in codon groups. A CODON is a grouping of three nitrogen bases in mRNA that carry the code for an amino acid.

G A

C

G A

U

codon codon

Transfer RNA (tRNA)tRNA Has a clover-leaf shapetRNA carries an amino acid at one end andan anticodon at the other end.

anticodon

U A C

amino acid

ANTICODONThe anticodon is located on tRNA

The anticodon is the “deciphered” mRNA code.EX:mRNA codon: AUGtRNA anticodon: UACThe tRNA also picks up the amino acid that corresponds to the mRNA codon

A AC

GAU

U AC

CodonAnticodon

AMINO ACID CHARTThis chart is used to find the appropriate amino acid using mRNA codons.

What would be the amino acid for the mRNA codon UGG?

  U C A G  

U PhenylalaninePhenylalanineLeucineLeucine

SerineSerineSerineSerine

TyrosineTyrosineStopStop

CysteineCysteineStopTryptophan

UCAG

C LeucineLeucineLeucineLeucine

ProlineProlineProlineProline

HistidineHistidineGlutamineGlutamine

ArginineArginineArginineArginine

UCAG

A IsoleucineIsoleucineIsoleucineMethionine

ThreonineThreonineThreonineThreonine

AsparagineAsparagineLysineLysine

SerineSerineArginineArginine

UCAG

G ValineValineValineValine

AlanineAlanineAlanineAlanine

Aspartic AcidAspartic AcidGlutamic AcidGlutamic Acid

GlycineGlycineGlycineGlycine

UCAG

Firs

t Bas

e

Second Base

Third

Bas

e

mRNA codon UGG is the amino acid Tryptophan

TRANSLATIONmRNA at the ribosome in the cytoplasmHow many amino acids would be present in the protein coded for by this mRNA strand?

mRNA

G A AC

AU

AU

A AGU

ribosome

TRANSLATION6. tRNA assists by bringing an amino acid to the ribosome

7. tRNA matches its anticodon with the codon of mRNA to place the amino acid in the correct sequence

G A AC

AU

AU

A AGU

U A C

Methionine

G A AC

AU

AU

A AGU

TRANSLATION

Isoleucine

A U U

Methionine

U A C

Peptide Bond

Methionine

U A C U U G

LeucineLeucine

U U G

Isoleucine

A U U

Peptide Bond

STOP

A U U

G A AC

AU

AU

A AGU

Methionine Leucine

TRANSLATION

Isoleucine STOP

Stop CodonA special codon called a STOP CODON marks the end of the gene and protein synthesis.

Polypeptide Chain - A Protein8. The amino acids bond with peptide bonds and form a polypeptide chain or protein.

polypeptide = protein

peptide

bonds

amino acid

REVIEWING TRANSLATIONProtein is made5. mRNA leaves nucleus, goes to ribosome in cytoplasm 6. tRNA assists by bringing an amino acid to the ribosome7. tRNA matches its anticodon with the mRNA codon putting amino acids in the correct sequence8. amino acids bond, forming a protein

click to play animation

TRY THIS!

Transcribe and translate this segment of DNA:

TACACCTGCGCATAG

DNA: TACACCTGCGCATAGmRNA: AUGUGGACGCGUAUCtRNA: UACACCUGCGCAUAG

Amino Acids: Met-Try-Thr-Arg-Iso

ANSWER

ChromosomeSmall section of this chromosome may contain MANY genes

GENE – A gene is a section of DNA that has hundreds or

thousands of base pairs

Sections within a gene

CODON

Start Condon

TAC

Codes for protein

Codon base triplets

Examples ATC CCG

Stop Codon

ATT, ATC, or ACT

REVIEW

SUMMARYTranscription Translation

G

A

C

G

A

U

A

A

T

T

T

C

C

A

G

G

CG

DNA mRNA

A U U

Amino Acid

tRNA Protein

Occurs in the

Occurs in the

DNA

DNA has the master code

mRNA is made, copying DNA’s code

A protein is made

Works Cited

“3D Protein Structure” Online Image, June 5, 2006 U.S. Department of Energy Human Genome Program, http://www.ornl.gov/TechResources/Human_Genome/graphics/slides/images/ras.gif