DNAWATSON AND

CRICK

DOUBLE HELIX

1953

DNA FUNCTION•CONTROL CELL FUNCTIONS•STORE HEREDITARY INSTRUCTIONS•COPY THOSE HEREDITARY INSTRUCTIONS TO A NEW GENERATION•CHANGE FOR EVOLUTION•GIVE INSTRUCTIONS FOR PROTEIN SYNTHESIS

Four nucleotides form DNA

• Five carbon sugar ( deoxyribose )• phosphate group• nitrogen-containing base:adenine, guanine, thymine, cytosine

NITROGENATED BASE

SUGAR(RIBOSE)

PHOSPHATE GROUP

NUCLEOTIDE

A

GUANINE

GENERAL STRUCTURE OF A NEUCLOTIDE

TitleRIBOSE

Title

Title

Title

Title

Title

DEOXYRIBOSE

-

-

TIMINA

GUANINA

PP P -

DNA structure• Two parallel strands of nucleotides

• twisted into a double helix• Adenine -- Thymine• Guanine -- Cytosine• linked by hydrogen bonds

COMPLEMENTARY BASES

THYMINE ADENINE

GUANINE CITOSINE

DNATHE NITROGENATED BASES UNITE BY HYDROGEN BONDS

DNA StructureA-A-T-T-G-G-C-C-T-T-G-G-A-A-T-T-G-G-C-C-G-G-A-A-C-C-A-A-G-G-

DNA StructureA-A-T-T-G-G-C-C-T-T-G-G-A-A-T-T-G-G-C-C-G-G-A-A-C-C-A-A-G-G-

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

DNA DUPLICATION

NUCLEUS

DUPLICATION

THE DNA UNWINDSEACH PARENT STRAND IS CONSERVEDA NEW COMPLEMENTARY STRAND IS

ASSEMBLED

adenine always pairs with thymineguanine always pairs with cytosine

DNA DuplicationA-A-T-T-G-G-C-C-T-T-G-G-A-A-T-T-G-G-C-C-G-G-A-A-C-C-A-A-G-G-

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

DNA DuplicationA-A-T-T-G-G-C-C-T-T-G-G-A-A-T-T-G-G-C-C-G-G-A-A-C-C-A-A-G-G-

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

THE DNA UNWINDS

DNA DuplicationA-A-T-T-G-G-C-C-T-T-G-G-A-A-T-T-G-G-C-C-G-G-A-A-C-C-A-A-G-G-

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

THE DNA UNWINDSEach nucleotide templates thecomplementary one of thenew strain.

-T-A-C-G

DNA DuplicationA-A-T-T-G-G-C-C-T-T-G-G-A-A-T-T-G-G-C-C-G-G-A-A-C-C-A-A-G-G-

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

THE DNA UNWINDSEach nucleotide templates thecomplementary new strain.

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

DNA DuplicationA-A-T-T-G-G-C-C-T-T-G-G-A-A-T-T-G-G-C-C-G-G-A-A-C-C-A-A-G-G-

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

THE DNA UNWINDSEach nucleotide templates thecomplementary new strain.EACH PARENT STRAND IS CONSERVEDA NEW COMPLEMENTARY STRAND IS ASSEMBLED

adenine always pairs with thymineguanine always pairs with cytosine

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

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

RNA

DNAWATSON AND CRICK

DOUBLE HELIX

1953

CELLULAR CONTROLSACID NUCLETIC STRUCTURE

DNA RNA

DOUBLE chains in all thecells

SIMPLE chain in all the cells

CELLULAR CONTROLGIVES THE MESSAGES

EXPRESION OF THE GENETIC INFORMATION(PROTEIN SYNTHESIS)

NUCLEIC ACIDSSTRUCTURES

DNA RNA

DOUBLE HELIX SINGLE HELIX

store hereditary info protein synthesis

Deoxyribose, Thymine Ribose, Uracil

TRANSCRIPTION TRANSLATIONproteins

DNA DUPLICATION

RNATRANSCRIPTION

NUCLEUS

AC

A

T C G T A AG

C TC

C

TG

TA

G C A T T C

G

AG

G

TRANSCRIPTION

AC

A

T C G T A AG

C AC

C

GG

T

G

CTTACGA

TG

T

CG

TRANSCRIPTION

AC

CC

T C G T A AG

C A

GG

T

G

CTTACGA

TG

T

GC

UUACGA

TRANSCRIPTION

RNA

DNA DUPLICATION

RNATRANSCRIPTION

PROTEINS

TRANSLATION

NUCLEUS

RIBOSOMES

TRANSCRIPTION

TRANSLATION

PROTEIN SYNTHESIS

TYPES OF RNA

"G ives th e m essag e"P ro te in S eq u en c e

m R N AM E S S A N G E R

"B u ild s th e P ro te in "Is 6 0 % o f th e R ib osom e

rR N AR IB O S O M A L

"Tran s la te th e lan g u ag e"A ttac h an am in oac id to a cod on

tR N ATR A N S F E R E N C E

R N ATyp e t it le h e re

TRANSLATION

MET ALA

PHE

GLY

THR

mRNA

AMINOACIDS

GGUU UU

GGCC AA CC CC AA

GGAAAA

GGGG CCUU UU UUGG CC UU AAAA CC

PROTEINA

SECUENCIA DE AMINOACIDOS

MET ALA GLY PHE THR ILE SER

PROTEIN

SEQUENCE OF AMINOACIDS

RNA

DNA

PROTEIN

REPLICATION

TRANSCRIPTION

TRANSLATION