dna shireen rudina. ingegneria biologica equipe de dibattito
TRANSCRIPT
DNA
Shireen Rudina
ingegneria biologica
Equipe de dibattito
DNA is the basis of life
• In every living organism, every cell
• In eukaryotes, found in the nucleus as chromatin
Why is DNA important?
• Forensics and paternity tests
• Personalized medicine
• Gene therapy
• Explains the differences between species and individuals
What are some of the barriers we need to break to extract DNA?
1. Cell wall
2. Ribosome
3. Golgi complex
4. Nuclear membrane
5. Cell membrane
4 DNA Nucleotides
Erwin Chargaff
• Analyzed the four nucleotides• In DNA of ANY species:– amount of A always equals amount of T– same with G and C
Rosalind Franklin
• X-ray crystallographer• Nobel Prize went to Watson and Crick• The X-ray diffraction image of DNA she made
was used (stolen!) by Watson to prove the 3D structure of DNA
Double Helix- Watson & Crick
Helix with Legos
• Red=A
• Blue=C
• Green=G
• Yellow=T
Why can’t you see the double helix in the DNA we extracted?
1. The extraction was incorrect.
2. The double helix is microscopic (very small)
3. There are not double helices in the chromatin
DNA StructureShape= Double Helix
Antiparallel
Sugar-Phosphate backbone- phosphodiester bonds (covalent)
Complementary base pairs (Chargaff’s Rule) - hydrogen bonds
A=T CΞ G
If one strand of DNA is ACCTGG, what is the complementary strand?
1. TGGCTT
2. ACCTGG
3. TGGACC
4. CTTGCC
The sequence of bases is important
• It is a code!• It codes for proteins, which perform all the
functions of the body
What is the monomer of proteins?
1. Amino acids
2. Nucleotides
3. Sugars
4. Phospholipids
20 amino acids
START
Why is it beneficial for DNA to be double stranded?
Why is the sequence important?
• Everyone’s is different
• Restriction enzymes cut at different points
Murder Case