Download - DNA Structure & Function
![Page 1: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/1.jpg)
DNA Structure & Function
![Page 2: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/2.jpg)
You Tube IndexDNA Structure (in order of usefulness)• DNA Structure– http://glencoe.mcgraw-hill.com/sites/9834092339/student
_view0/chapter14/dna_structure.html
• Good (factual, but dry)– http://www.youtube.com/watch?v=tknYrU98rBk&feature=
fvwrel
• Structure & Prot synthesis– http://www.youtube.com/watch?v=FUA6_Ucw3i4For history of discovery of DNA and structure see the Powerpoint “DNA History”
![Page 3: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/3.jpg)
Watson & Crick(credited with discovery of STRUCTURE of DNA, though
their work relied heavily on the work of others)
![Page 4: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/4.jpg)
DNA Functions• Carries genetic code for life processes• Can replicate to continue life…• Lengths of DNA (genes) code for
production of proteins that are– structural– functional– & are 95% of human body!
!!!
![Page 5: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/5.jpg)
DNA Packaging!!!
![Page 6: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/6.jpg)
![Page 7: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/7.jpg)
Role of DNA Terms(over the course of this AS & others you will understand all of these terms)
• Genome – all the DNA in a cell• Genes – sections of DNA coding for
the production of proteins• Chromosomes - • Chromatid• Nucleus - • Nuclear Membrane• Chromatin• DNA• Nucleotides - the repeating unit of
DNA• Protein• mRNA
• Prokaryote – cells / organisms without a nucleus
• Eukaryote – cells / organisms with a nucleus
• Protein synthesis – process where protein is manufactured
• Mitochondria – organelle (“little organ”) in a cell where energy (ATP) is produced
• Cytoplasm • Enzymes• Metabolism• Cell division• Centromere
![Page 8: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/8.jpg)
Nucleic Acids• Two types:– DNA – Deoxyribose nucleic acid (location: nucleus)– RNA – Ribose nucleic acid (location: nucleus +
cytoplasm)• Made of repeating units: nucleotides• Nucleotide made of:– Nitrogen base– A 5-carbon sugar(deoxyribose in DNA,ribose in RNA)– Phosphate group
!!!
![Page 9: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/9.jpg)
Sweet Difference
![Page 10: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/10.jpg)
DNA Structure
The two strands are “anti parallel”One strand runs from 3’ to 5’ the other 5’ to 3’
!!!
![Page 11: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/11.jpg)
DNA Structure• Shape: double helix (like a twisted ladder)
![Page 12: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/12.jpg)
DNA Structure• 4 bases:
– A – Adenine T – Thymine – G – Guanine C – Cytosine
• “Rungs” - Bases held together by hydrogen bonds– A pairs with T (two bonds)– G pairs with C (three bonds)
• “Backbone”– Sugars joined to phosphates* by “phosphodiester” bonds!
• Complementary vs template– Since you find a C opposite a G… etc thesecond strand is said to be complementaryto the first.- And: the first strand can be used as a template to make a new complementary strand
!!!
In RNA the base U (Uracil) replaces thymine
![Page 13: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/13.jpg)
* Pyrimidines vs Purines
• The “pyrimidine bases” are:– C & T (one ring
structure)• The “purines” are:– A & G (double ring
structure)
To remember: purines = two rings
![Page 15: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/15.jpg)
Length of DNA in organisms
• Only 4 bases BUT one DNA molecule = millions of bases long
• Human: 6 billion base pairs• Bacteria: ~ 4.3 million bases• Viruses…..
![Page 16: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/16.jpg)
ΦX174 Bacteriophage DNA SequenceBacteriophage = virus affecting bacteria
9 genes, each codes for one protein.
Genes overlap, one genes is highlighted.
Human genome = 1 million times longer
![Page 17: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/17.jpg)
![Page 18: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/18.jpg)
How much DNA in humans?
• ~ 100,000,000,000,000 cells in the human body
• 2m of DNA in each cell (3-5cm per chromosome)
• DNA length in kilometres:– 200,000,000,000 km
• How many times to the moon? (moon = 184,000km)– 1,086,957 times
• How many times to the sun & back? (= 300,000,000km)– 667 times
![Page 19: DNA Structure & Function](https://reader033.vdocuments.site/reader033/viewer/2022061522/56816195550346895dd139cb/html5/thumbnails/19.jpg)
DNA Structure END