DNA structureMutations & Cancer
DNA and RNA
• DNA= __________________________
• RNA= __________________________
• DNA and RNA are called Nucleic acids: Nucleic because: _______________________
Acids: ________________________________
DNA and RNA
• Proteins break down to ______________• Nucleic acids break down to ______________
• Proteins and nucleic acids are ____________• Amino acids and nucleotides are ___________
DNA and RNA
• Nucleotides have 3 components:
1. __________________
2. __________________
3. ___________________
DNA vs. RNA
DNA • Sugar: Deoxyribose
• Bases: ____________________________________________________
RNA • Sugar: Ribose
• Bases: ____________________________________________________________
Types of bases: purines and pyrimidines
Types of sugar: Ribose and deoxyribose
Nucleotides
Nucleotides
DNA
• dATP• ______• dGTP • ______
• Or dNTP
RNA • ATP • ______• CTP • ______
• Or NTP
DNA structure
DNA backbone= blue
Composition????
DNA structure Backbone:__________________________________
Variable region:______________
DNA Summary
• Sugar: _______________ • Bases: _______________• Backbone: _______________• Variable: _______________
• DNA is double stranded (2 strands) A=T C=G
DNA vs. RNA
RNA summary
• Sugar: _______________• Bases: _______________• Backbone: _______________• Variable: _______________
• RNA is single-stranded
Human genome
Human genome
• The double stranded DNA is wrapped around special proteins called_______________
• Histones pack together in on multiple levels
• The most packaged form of DNA is called _______________
Human genome
• Humans have 23 pairs of chromosomes: 1. 22 pairs of _______________2. 1 pair of _______________
• Humans are DIPLOID- carry a pair for each chromosome (a maternal chromosome and a paternal one)
Karyotype
________________________________________________________________________________________________
Function of DNA
•DNA contains ________ that code for proteins
•But how much of it is actually coding sequences?
Composition of our genome
Function of DNA
Function of DNA
• Sequence of bases is very unique for each gene.
• The bases are read __ at a time
• The sequence codes for a specific protein
Mutations
•Mutation= ________________________________
•Mutations can be inherited (from parents) or acquired (smoking, sunlight)
Mutations types:
• 1. substitution (point mutation) : ________________________________
-Transition- purine purine - Pyrimidine pyrimidine
-Transversion- purine pyrimidine - Pyrimidine purine
Mutation types:
Remember: Purines are A and G Pyrimidines are C U and T
Mutation types:
• 2. Insertion/ deletions: ___________________________________
Causes of mutations:
1. Errors in DNA replication (during the S phase)
2. ______________3. X-rays 4. Environmental toxins5. __________________6. Asbestos 7. Mutations can be _____________
Mutations: Good or bad?
•Mutations are good: Lead to genetic variability, key driver to evolution
•Mutations are bad: Cause many diseases such as CANCER
Cancer
• Disease that is characterized by uncontrolled excessive cellular proliferation.
•Mainly caused by mutations
• Controlling genes lose their function
Genes and cancer
___________________• Genes that code for
regular proteins,
• If they are over-activated due to mutation, they become oncogenes
• Oncogenes lead to cancer progression
_____________________• Genes that prevent
cancer progression
• ex: genes for the cell cycle checkpoints
• When they are inactivated due to mutation, cancer will progress