New Core CurriculumNew Core Curriculum

Classical GeneticsClassical Genetics

Foundations of Scientific ProcessFoundations of Scientific Process

Chromosomes are highly condensed structures in the nucleus of every cell built from DNA wrapped around series of histone proteins

Chromosomes are highly condensed structures in the nucleus of every cell built from DNA wrapped around series of histone proteins

GenomeGenomethe complete package of genetic material (all DNA) for a living organism , organized in 23 pairs of chromosomes

In humans the entire stretch of DNA polymer is made of ~ 3·109 monomer units

GeneGene is a stretch of DNA that contains the instructions for making a protein

GenomeGenomethe complete package of genetic material (all DNA) for a living organism , organized in 23 pairs of chromosomes

Chromosomes are highly condensed structures in the nucleus of every cell built from DNA wrapped around series of histone proteins

DNA segment that encodes

for a protein

when and where it is made

new definition of a Gene

Chemical Composition of Living Matter

DNA, RNA: 4 nucleic bases

Proteins: 20 amino acids

smallsmall subset of atoms provides an subset of atoms provides an extensiveextensive molecular diversity molecular diversity

6 atomic constituents 6 atomic constituents C, H, N, O, P, S C, H, N, O, P, S

build 99.6% of living matter build 99.6% of living matter

3 essential biomolecules for existence and continuation of life:

All life is based on 6 chemical elements that are arranged in more complex structures (DNA, RNA, proteins)

variable units

Adenine

Guanine

Thymine

Cytosine

4 Nucleic Bases:Adenine (A), Thymine (T), Guanine (G), and Cytosine (C)

Genetic code for DNAGenetic code for DNA 2 strands of backbone

locked by base pairs

double helix

Adenine

Guanine

Thymine

Cytosine

4 Nucleic Bases:Adenine (A), Thymine (T), Guanine (G), and Cytosine (C)

Genetic code for DNAGenetic code for DNA

Pairing

A-TG-C

2 strands of backbone

locked by base pairs

double helix

It is the wave function that describes the particle's It is the wave function that describes the particle's motion when it travels unobserved.motion when it travels unobserved.

H-bonding interactions help cross-link:

example:Kevlar derives part of its high strength from inter-molecular hydrogen bonds on neighboring polymer chains and aromatic (ring) stacking interactions between stacked strands

cross-linking via H-bonding

H-bonding attractive force between one electronegative atom (O,F, N) and a hydrogen covalently bonded to another electronegative atom.

0.34 nm

The structure of DNA: chemical variabilitychemical variabilitynucleic bases in arbitrary sequencenucleic bases in arbitrary sequence

repetitive structurerepetitive structure• backbonebackbone• uniform helixuniform helix

Notice that the widths of the pairs A-T and G-C are equal

base -sequence encodes the meaning

Watson and Crick

The structure of DNA: chemical variabilitychemical variabilitynucleic bases in arbitrary sequencenucleic bases in arbitrary sequence

Notice that the widths of the pairs A-T and G-C are equal

base -sequence encodes the meaning

Physically Repetitive, Chemically Variable

repetitive structurerepetitive structure• backbonebackbone• uniform helixuniform helix

The structure of DNA:

Why is this significant ?

chemical variabilitychemical variabilitynucleic bases in arbitrary sequencenucleic bases in arbitrary sequence

Notice that the widths of the pairs A-T and G-C are equal

base -sequence encodes the meaning

Physically Repetitive, Chemically Variable

repetitive structurerepetitive structure• backbonebackbone• uniform helixuniform helix

The structure of DNA:

Physically Repetitive, Chemically Variable

Readability requires some sort of regular structure that can be algorithmically sifted through (semi-conservative replication)

Chemically variability in sequence provides a meaning and a genetic diversity

Notice that the widths of the pairs A-T and G-C are equal

chemical variabilitychemical variabilitynucleic bases in arbitrary sequencenucleic bases in arbitrary sequence

base -sequence encodes the meaning

repetitive structurerepetitive structure• backbonebackbone• uniform helixuniform helix

ONE COPY

TWO COPIES

G

A

C

T

C

T

G

A

G

A

C

T

C

T

G

A

+ mix of four subunit bases

A CG T

CT A

G

Sequence info is kept by separated strand

G

A

C

T

C

T

G

A

G

A

C

T

C

T

G

A

EXACT COPY EXACT

COPY

Semi-conservative Replication: DNA DNA

DNA polymerase

Provides opportunity for introduction and

preservation of Novelty

semi-conservative replication of DNA

Cytosine

4 Nucleic Bases:Adenine (A), Uracil (U), Guanine (G), and Cytosine (C)

UracilAdenine

Guanine

Genetic code for RNAGenetic code for RNA 1 strands of backbone with

base pairs

single helix

Triplet of RNA bases (codon) translates into a particular amino acids

What Is A Virus?: Genetics Review

The structure of DNA:

Meaning of a genetic code ProteinsMeaning of a genetic code Proteins

variable sequence (string) built of variable sequence (string) built of 20 amino acids (building blocks) 20 amino acids (building blocks)

strings of amino acids fold up into strings of amino acids fold up into particular shapeparticular shape

Shape governs the Function (Meaning)Shape governs the Function (Meaning)

Hereditary Material:Hereditary Material:

Proteins (backbone + 20 amino acids)DNA (backbone + 4 nucleic bases)

Protein vs. DNAProtein vs. DNA

Hereditary Material:Hereditary Material:

Proteins (backbone + 20 amino acids)DNA (backbone + 4 nucleic bases)

Protein vs. DNAProtein vs. DNA

32P-labeled DNA

35S-labeled Protein

Hershey-Chase experiment:Hershey-Chase experiment:

Virus infects Bacteria

Hereditary Material:Hereditary Material:

Proteins (backbone + 20 amino acids)DNA (backbone + 4 nucleic bases)

Protein vs. DNAProtein vs. DNA

32P-labeled DNA

35S-labeled Protein

2/3 within bacterium2/3 within bacterium

1/4 within bacterium1/4 within bacterium

Hershey-Chase experiment:Hershey-Chase experiment:

Virus infects Bacteria

1) DNA encodes RNA2) RNA encodes Proteins3) Proteins encode shape/function

Genetic information (the MEANING) is encoded in the SEQUENCE of basis along the DNA strand; DNA is not a direct template for protein synthesis;

The Central Dogma of The Central Dogma of Molecular Biology:Molecular Biology:

DNA RNA Protein

The History of Classical GeneticsThe History of Classical Genetics

NATURE|Vol 441|25 May 2006