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Chromosomes breaks

Illustrate, define and describe single break chromosomes:
- One arm of one chromosome
- One arm of two chromosomes
Illustrate, define and describe double break chromosomes:
- One arm of one chromosome
- Both arms of one chromosome

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Illustrate, define and describe single break chromosomes:

DNA are double stranded alpha-helix structure. The two complementary strands of DNA are held together by hydrogen bonds. Single break chromosomes are defined as single strand break lesion or gaps in only one of the two strands of a double helix. Since the other strand is intact, it can be used as a template to guide the correction of the damaged strand. (1) There are a several excision repair mechanisms to repair one of the damaged strand of the double stranded DNA. (1) These excision repair mechanism remove the damaged nucleotide and replace it with undamaged nucleotide complementary to that found in the undamaged DNA strand. Base excision repair (BER) acts to repair damage to a single base caused by oxidation, alkylation, hydrolysis, or deamination. DNA glycosylase act to remove the damaged base. The missing space is ...

Solution Summary

DNA damage can lead to genome instability if left not repaired. There are two major types of DNA damage, including single stranded DNA lesions and double stranded DNA lesions. Single stranded DNA lesions is when one copy of the DNA is severed or nick, while the other copy is normal. Double stranded DNA lesions is when both copies of the DNA is severed. Double stranded breaks (DSBs) is the worst of the DNA damage, and can lead to cell death if left not repaired. DSBs break is repaired by homologous recombination, while SSBs is repaired by excision repaired mechanisms.