3 - Physiology Essentials 100 PDF

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Physiology Essentials 100...

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Mutations: Which of these is the more harmful mutation? a) Point mutation b) Frameshift mutation c) Inversions and Translocation mutations b (frameshift mutation)

Mutations: Types of mutations: Inversions and Translocation - More extensive DNA alterations can result from inversions and translocation of large chunks of ________ DNA

Mutations: Types of mutations: Inversions and Translocation - Obviously, these can be very _____________ to a cell damaging

Mutations: Cause of mutations: - ___________ mutations are very rare, usually not a problem for a living cell. These occur (at a rate of about 1 in 1 billion bases put in place by DNA polymerase) spontaneous Mutations: Cause of mutations: Spontaneous mutations - This very, very (low/high) rate is due to the proofreading capability of DNA polymerase - it can literally detect when it is made an error and replace it low Mutations: Cause of mutations: Induced mutations - chemicals (such as __________ acid on the right) can induce mutations at a higher

rate than is found spontaneously ; causes deamination (change base pair characteristic) nitrous

Mutations: Cause of mutations: Induced mutations - chemicals: deamination due to nitrous acid of cytosine --> ________, this is the worst uracil

DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include - _______ ________ Repair: point mutation base excision DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Base Excision Repair: - Uracil DNA __________ recognizes the uracil in DNA and remove it from the molecule (removes uracil) glycosylase Mutations: Cause of mutations: Induced mutations - ___________ light can also cause a higher than expected mutation rate in DNA (e.g. by forming thymine dimer - lose a hydrogen bond and thymine binds to thymine = causes cell to die) ultraviolet

DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Base Excision Repair: - An ______ site is created --> baseless site AP DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Base Excision Repair: - _______ _____________ recognizes the AP site and breaks the phosphodiester bonds, nicking the DNA strand (take out sugar and phosphate backbone) Ap endonuclease

DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Base Excision Repair: - DNA polymerase (I/II/III) resynthesizes the missing nucleotide and DNA ____1______ seals the nicks I (1) Ligase DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include - _______ ________ Repair: essential for all living cells, fix many different types Nucleotide excision DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Nucleotide Excision Repair: - ____________ complex identifies the damaged region uvrAB DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Nucleotide Excision Repair: - ____________ leaves the complex uvrA (transporter protein, only function is to transfer uvrB and leave) DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Nucleotide Excision Repair: - _____1_______ binds to uvrB and acts as an ______2_______ (cutting on both sides of the damaged region) --> recognition point for uvrD (1) uvrC (2) endonuclease DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Nucleotide Excision Repair: - ____________ will then come in and remove the damaged region, creating a gap uvrD DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Nucleotide Excision Repair: - DNA polymerase I binds to the 1(gap/nick) and resynthesizes the missing nucleotides and DNA ligase seals the 2(gaps/nicks) (1) gap (2) nicks DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include - _____________ Repair: mainly used to fix thymine dimer photoreactivation

DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Photoreactivation Repair: - ___________ dependent repair system --> not essential in bacteria, found in plants and certain bacterial organisms (not found in humans) light

DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Photoreactivation Repair: - the enzyme ____________ recognizes and binds to the pyrimidine dimer photolyase

DNA repairs: Complex Mechanisms Exist for Repairing DNA in Bacteria These mechanisms include... Photoreactivation Repair: - It breaks the bond between the two _____________ (e.g. thymine), restoring normal base pairing pyrimidines

Viral Replication Strategies: How do viruses replicate? - Replication strategies vary widely depending on _________ type genome...