CHAP 16: DNA (NUCLEIC ACIDS AND INHERITANCE)

Watson and Crick

Who are the scientists with an elegant DOUBLE-HELICAL MODEL FOR THE STRUCTURE OF DEOXYRIBOONUCLEIC ACID (DNA)?

DNA

It is YOUR GENETIC ENDOWNMENT. CONTAINED IN 46 CHROMOSOMES YOU INHERITED AND THE MITOCHONDRIA YOU INHERITED FROM MOTHER.

Nucleic Acids

These are UNIQUE IN THEIR ABILITY TO DIRECT THEIR OWN REPLICATION.

DNA

This program DIRECTS THE DEVELOPMENT OF BIOCHEMICAL, ANATOMICAL, PHYSIOLOGICAL AND BEHAVIORAL TRAITS.

Heterogeneity and specificity of function

What MADE PROTEIN SEEM THAT IT IS THE GENETIC MATERIAL BUT CHALLENGED BY EXPERIMENTS WITH BACTERIA AND VIRUSES?

Frederick Griffith

WHO DISCOVERED THE GENETIC ROLE OF DNA STARTING WITH RESEARCH IN 1928?

Streptococcus Pneumoniae

WHAT IS THE BACTERIUM THAT GRIFFIFTH STUDIED THAT CAUSED PNEUMONIA IN MAMMALS?

Streptococcus Pneumoniae

• ONE STRAIN WAS HARMLESS

• OTHER STRAIN WAS PATHOGENIC (DISEASE CAUSING)

Transformation

This phenomenon is now DEFINED AS CHANGE IN GENOTYPE AND PHENOTYPE DUE TO THE ASSIMILATION OF EXTERNAL DNA by a cell.

Oswald Avery

This AMERICAN BACTERIOLOGIST FOCUSED ON (3) MAIN CANDIDATES AS TRANSFORMING SUBSTANCE: DNA, RNA AND PROTEIN.

DNA, RNA, and Protein

THESE ARE THE (3) MAIN TRANSFORMING SUBSTANCE CANDIDATES FOCUSED BY OSWALD AVERY.

Oswald Avery, Maclyn McCarty, and Colin MacLeod

Who were the ones WHO ANNOUNCED THAT THE TRANSFORMING SUBSTANCE WAS DNA IN 1944?

Bacteriophage

This was FOUND IN OTHER STUDIES THAT THIS BACTERIA BY VIRUS BACKED UP THE EVIDENCE THAT DNA WAS THE GENETIC MATERIAL.

Alfred Hershey and Martha Chase

IN 1952, WHO SHOWED THAT DNA WAS THE GENETIC MATERIAL OF THE PHAGE T2?

T2 Phage

This CONSISTING ALMOST ENTRLEY OF DNA AND PROTEIN, ATTACKS ESCHERICHIA COLI, A COMMON INTESTINAL BACTERIUM OF MAMMALS.

T2 Phage

THIS CAN QUICKLY TURN E. COLI INTO A ____ PRODUCING FACTORY THAT RELEASES PHAGES WHEN THE CELL RUPTURES.

Erwin Chargaff

Who DEVELOPED A SERIES OF RULES BASED O A SURVEY OF DNA COMPOSITION IN ORGANISMS BACK 1947?

Erwin Chargaff

HE KNEW THAT DNA WAS A POLYMER OF NUCLEOTIDES CONSISTING OF A NITROGENOUS BASE, DEOXYRIBOSE, AND PHOSPHATE GROUP.

Chargaff’s rules

1. In any one species, the FOUR BASES ARE FOUND IN CHARACTERISTIC, BUT NOT NECESSARILY EQUAL RATIOS.

2. In all organisms, the NUMBER OF ADENINES IS APPROX. EQUAL TO THE NUMBER OF THYMINES, SAME WITH GUANINE & CYTOSINES.

3. HUMAN DNA IS 30.3% ADENINE, 30.3% THYMINE, 19.5% GUANINE AND 19.9% CYTOSINE.

Wilkins and Franklin

They USED X-RAY CRYSTALLOGRAPHY TO STUDY THE STRUCTURE OF DNA.

Crystallography

In THIS TECHNQUE, X-RAYS ARE DIFFRACTED AS THEY PASS THROUG ALIGNED FIBERS OF PURIFIED DNA.

Diffraction Pattern

It CAN BE USED TO DEDUCE THE 3 DIMENSIONAL SHAPE OF MOLECULES

James Watson

WHO LEARNED FROM THE RESEARCH THAT DNA IS HELICAL?

Antiparallel

In THEIR MODEL, THE TWO SUGAR PHOSPHATE BACKBONES ARE ____ WITH THE SUBUNITS RUNNING IN OPPOSITE DIRECTIONS.

Purine-Purine

THIS PAIR OF NUCLEOTIDES IS TOO WIDE, and does not fit the uniform diameter.

Pyrimidine-Pyrimidine

THIS PAIR OF NUCLEOTIDES IS TOO SHORT, and does not fit the uniform diameter.

Pyrimidine-Purine

Only THIS PAIR PRODUCES THE 2-NM DIAMETER INDICATED BY THE X RAY DATA.

2 Hydrogen bonds

Based on the details of their structure, ADENINE FORMS HOW MANY BONDS WITH THYMINE?

3 Hydrogen Bonds

Based on the details of their structure, GUANINE FORMS HOW MANY BONDS WITH CYTOSINE?

Watson and Crick

WHO DISCOVERED THE DOUBLE HELIX BY BUILDING MODELS TO CONFORM TO X RAY DATA?