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