DNA and RNA

The Chain of Life

DNA

• DNA – Deoxyribonucleic Acid

• DNA … RNA…proteins… make up cells…life

• DNADNA is often called the blueprint of life..

DNA

• Why important to you?1) every new cell needs copy of DNA to make proteins

2) pass on DNA to offspring

3)medical benefits such as cures for diseases,

4)better food crops and animals

Who discovered structure? - movie

• James Watson • Francis Crick

A HISTORY OF DNAA HISTORY OF DNA

• Discovery of the DNA double helixDNA double helix

A. Frederick Griffith – Discovers that a factor in diseased bacteria can transform harmless bacteria into deadly bacteria (1928)

B. Rosalind Franklin - X-ray photo of DNA.(1952)

C. Watson and Crick - described the DNA molecule from Franklin’s X-ray.(1953)

DNA

• Made up ofpolymers – composed of sub units called monomers

DNA

• DNA and RNA repeating units = nucleotides – 2 together form DNA chain

DNA

• Called a DOUBLE HELIX• Held together with hydrogen bonds : share 1

electron

DNA

• Nucleotides – 3 parts5 carbon sugar called deoxyribosephosphate groupnitrogen base ( 4 kinds)

DNA

• adeninepurines: 2 rings

guanine

DNA

• thyminepyrimidines : 1 ring

cytosine

DNA

• A = T with two hydrogen bondsC = G with three hydrogen bonds

• DNA structure movie

DNA by the numbersDNA by the numbers• Each cell has about 2 meters of DNA.

• The average human has 75 trillion cells.

• The average human has enough DNA to go from the earth to the sun more than 400 times.

• DNA has a diameter of only 0.000000002 m.

• It contains information equal to some It contains information equal to some 600,000 printed pages of 500 words 600,000 printed pages of 500 words each!!! each!!!

(a library of about 1,000 books)(a library of about 1,000 books)

The earth is 150 billion mor 93 million miles from the sun.

DNA is like a fingerprint because everyone’s is a little different!

How does the police look at DNA to figure out who committed a crime?

The DNA gets cut up by special scissors!!!

The scissors can only cut the same color!

All of the cut up pieces of DNA are different sizes.

BIG

LITTLE

A special machine sorts the DNA by size.

(Little pieces are fast, so they move faster to the bottom.) TOP

BOTTOM

We are ALL a little bit different!

Mrs. Nickerson’s DNA

Sara’s DNA

BIG

LITTLE

Soooo…. How do we tell people apart just by their DNA anyways???

Mrs. Nickerson’s DNA Sara’s DNA

Our DNA has different sizes of pieces so it makes a different pattern when it’s all

cut up.

                         

                         

                       

                       

Mrs. Nickerson’sSara

This is what it really looks like!!!

Mrs. Nickerson’s Sara

Is the red box around Mrs. Nickerson’s DNA or around Sara’s DNA?

?

DNA

• Replication : Unwind and Unziphydrogen bonds are broken with enzyme called helicasefree floating nitrogen bases come in and bond copying occurs

Replication…

• Replication flash

Movie

Replication full movie

Identical base sequences

Mutations

Wild type"Normal Gene" THE ONE BIG FLY HAD ONE RED EYEMissense THQ ONE BIG FLY HAD ONE RED EYENonsense THE ONE BIGFrameshift THE ONE QBI GFL YHA DON ERE DEYDeletion THE ONE BIG HAD ONE RED EYEDuplication THE ONE BIG FLY FLY HAD ONE RED EYEInsertion THE ONE BIG WET FLY HAD ONE RED EYEExpanding (P) THE ONE BIG FLY HAD ONE RED EYEExpanding (F1) THE ONE BIG FLY FLY FLY HAD ONE

RED EYEExpanding (F2) THE ONE BIG FLY FLY FLY FLY FLY FLY HAD

ONE RED EYE

RNA

• – synthesize proteins – Ribonucleic Acid

RNA

• Plants – photosynthesisAnimals – protein synthesis

RNA

• 3 Differences!1) 1 strand of nucleotides instead of 22) ribose not deoxyribose3) uricil not thymine

RNA - types

• Types- mRNA – messenger RNA – used to transmit information from DNA

-RNA Types

• t RNA – transfer RNA – single strand of RNA able to bend back upon itself so that the correct bases can bond together

-RNA Types

• - rRNA – ribosomal RNA – globular, not in a strand – main factor in ribosome organelles

Protein Synthesis – how proteins are made

• Proteins… polymers called polypeptides… specific sequence of amino acids… linked together by peptide bonds

Protein Synthesis

• 20 amino acids- genetic code = array of nitrogen base combination- 3 sequences on one side of chain = codon… AUG start code

All others…= 64 possibilities

Amino Acid Decoder Chart

-RNA Transcription – how RNA is made

• RNA enzyme polymerase unzips a DNA chain

• Hydrogen bonds occur between DNA and RNA

• Copies until it reaches stop code then triggers release

Transcription - movie

-RNA Translation

• assembling of protein molecules in mRNAcodons paired with anticodon

Translation - movie

• rRNA Bonds chain of Amino Acids to form a Polypeptide Protein