Teacher Notes This PPT was revised October 25

Teacher Notes This PPT was revised October 25, 2005. This PPT introduces scientist/history of DNA, DNA structure and RNA structure. There is a DNA Structure handout for this PPT. The DNA Scientists portion can be done using the book and review with this PPT.

DN A The Structure of DNA

Should acquaintance be forgot, And Auld Lang Syne!

And Auld Lang Syne! Name the organelle give its Ribosome: Endoplasmic Nucleus: Golgi Aparatus: control site Reticulum: where modifies, body proteins of and aids the sorts, cell; inare processing and contains made packages the carbohydrates, genetic materials material from the lipids (DNA) ERand for storage proteinsinfor the export cell or function. from the cell secretion outside the cell Endoplasmic Reticulum Nucleus Golgi Body Animal Ribosome Plant

And Auld Lang Syne! What is located in the nucleus? What type of organic compound is DNA? What is the monomer of DNA?

And Auld Lang Syne! What does the DNA of all these organisms have in common? They all share a universal genetic code.

And Auld Lang Syne! What is the name of these monomers? H amine group H N C OH R H carboxyl group variable R group H amine group H N H C R O C carboxyl group OH To what organic compound group do they belong?

And Auld Lang Syne! What does the chain of amino acids represent? Threonine Asparagine Arginine Glycine Proline Glycine Polypeptide Chain – A Protein Alanine

History of Heredity Why am I so gorgeous?

Gregor Mendel determined that traits were passed from generation to generation. But, I haven’t figured out how this happens

Frederick Griffith was working on a vaccine for Streptococcus pneumoniae He worked with 2 strains of the bacteria: ØSmooth capsule that causes disease ØRough capsule that does not cause disease

Frederick Griffith He added these bacteria strains, some dead and some living, to lab rats. These are his results:

Frederick Griffith Live Smooth Bacteria Live Rough Bacteria Dead Smooth Bacteria Live R+ dead S Bacteria

Griffith Proved: That somehow the dead bacteria have passed their disease-causing substance to the harmless, living bacteria. Griffith discovered a factor that could transform harmless bacteria into disease-causing bacteria

What was this substance called? DNA

Oswald Avery’s team determined that genes are composed of DNA

Erwin Chargaff Chargoff discovered that DNA has the same amount of adenosine as thymine and the same amount of cytosine as guanine. A = T and G = C AA AA T TT T T TT C CC G G G

Rosalind Franklin & Maurice Wilkins Franklin and Wilkins used x-ray to discover that DNA was a double helix.

Watson and Crick Watson & Crick won a Nobel Prize for discovering the structural model of DNA. They credited Wilkins and Franklin. Wilkins also got a Nobel Prize but Franklin did not. Rosalind had passed away and the Nobels are not awarded posthumously.

DNA is a Nucleic Acid What is a nucleic acid? Nucleic acids are one of the major organic compounds.

Auld Lang Syne! Nucleic acids contain C, H, N, O, P Are made up of nucleotide monomers Store genetic information Help make proteins Examples: DNA & RNA sugar nitrogen base phosphate Deoxyribo. Nucleic Acid

DNA Structure For what does DNA stand? What is the monomer for nucleic acids? What is the structure of this monomer? nucleotide phosphate sugar nitrogen base PO 4 (the 5’ end) 5 The numbers N base are the 4 Sugar 1 positions of the carbons 3 2 Deoxyribo. Nucleic Acid on the sugar. (the 3’ end)

A NUCLEOTIDE 1. Phosphate Group 3. 2. Nitrogen 5 -Carbon. Base Sugar 2. 5 -Carbon Sugar 1. Phosphate Group (Dexoyribose or Ribose) 3. 1. 3. Nitrogen Base 2. O O P O 3. 1. 2. O C H 2 C H 3 C O CH HC C H CH HO H O Nucleotides, too O C CH N N C O H

Nucleotides There are four nitrogen bases making up four different nucleotides. Purines Adenine A Guanine G N base Pyrimidines Thymine T Cytosine C

Chargaff’s Base Pair Rules Adenine always bonds with thymine. Adenine (A) to Thymine (T) A T The lines between the bases represent hydrogen bonds G C Guanine always bonds with Cytosine. Guanine (G) to Cytosine (C)

Pairing DNA Nucleotides What would is the a nucleotide? base be the pairing complementary rule? nucleotide pairing? Nucleotide P S N-b C G Rule A A to T A C to G T G

DNA DOUBLE HELIX 5’End 3’End ladder shaped molecule 3’End 5’End

Purpose of DNA Why do we have DNA? DNA contains our genetic codes For what does it code? for proteins What actually makes you look the way you do DNA or Proteins?

What is RNA? RNA stands for Ribo. Nucleic Acid DNA must have a “helper” molecule. RNA is a single stranded nucleic acid made up of monomers called nucleotides sugar phosphate nitrogen base

RNA Nucleotides A - Sugar (ribose) B - Phosphate C - Nitrogen base sugar nitrogen base phosphate B Name the parts of the nucleotide. A C

RNA Identify the parts of the RNA strand. Nitrogen Base Sugar (ribose) Phosphate Group

Rules for Base Pairing Cytosine pairs with Guanine C = G Adenine pairs with Uracil A = U Notice that RNA has Uracil (not thymine)

Rules for Base Pairing 3’ DNA strand C=G A=U C G A U G C T A RNA strand 5’ DNA strand

What is the function of RNA? Carries DNA’s message code Helps make protein Types of RNA ØMessenger RNA (m. RNA) ØTransfer RNA (t. RNA) ØRibosomal RNA (r. RNA)

Comparing DNA & RNA DNA RNA Sugar is deoxyribose √ Sugar is ribose √ Adenine base is present √ √ Cytosine base is present √ √

Comparing DNA & RNA DNA Guanine base is present Thymine base is present √ √ √ Uracil base is present Shape is double helix RNA √ √

Comparing DNA & RNA DNA RNA Shape is single stranded Located in nucleus √ √ √ Located in cytoplasm Stores genetic information √ √

Comparing DNA & RNA DNA RNA Functions in protein synthesis √ Composed of nucleotides Template for synthesis of proteins Transcribes the Template More than one type √ √ √

Works Cited