dna and rna the chain of life. dna dna – deoxyribonucleic acid dna … rna…proteins… make up...
TRANSCRIPT
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