BCH 5413- EXAM 1 2025/2026 EXAM
QUESTIONS AND ANSWERS | 100%
PASS
topoisomerase - 🧠ANSWER ✔✔relieves supercoiling in front of replication fork
Left-handed DNA - 🧠ANSWER ✔✔negative *under wrapped supercoiling
Right-handed DNA - 🧠ANSWER ✔✔positive *over wrapped supercoiling
Gel Electrophoresis: Matrix - 🧠ANSWER ✔✔1. agarose (polysaccharide)
2. polyacrylamide (neurotoxin)
Gel Electrophoresis: Sample possiblitiies - 🧠ANSWER ✔✔1. Eukaryotic genome
2. Bacterial genome
3. Viral genome
4. Plasmid
Digest with __ - 🧠ANSWER ✔✔EcoR1
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
1
, steps of Southern Blotting - 🧠ANSWER ✔✔1. Agarose gel electrophoresis of
DNA fragments
2. Denature DNA and blot (converts to ssDNA)
3. Southern Blot on filter
4. Block nonspecific DNA or protein then incubate with labeled probe
5. Photographic detection
6. Positive band "lights up"
Klenow fragments - 🧠ANSWER ✔✔large fragment of DNA polymerase, used to
extend primers
Stringency - 🧠ANSWER ✔✔Properties of hybridization conditions that dictate the
degree of base mismatch permitted between probe and DNA trage
Low stringency: Increase in number of mismatch (high background noise)
High stringency: Decrease in number of mismatch (low background noise) *high
temp, low salt
Gel filtration - 🧠ANSWER ✔✔Gel filtration chromatography uses
columns fi lled with porous resins that let in smaller
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
2
QUESTIONS AND ANSWERS | 100%
PASS
topoisomerase - 🧠ANSWER ✔✔relieves supercoiling in front of replication fork
Left-handed DNA - 🧠ANSWER ✔✔negative *under wrapped supercoiling
Right-handed DNA - 🧠ANSWER ✔✔positive *over wrapped supercoiling
Gel Electrophoresis: Matrix - 🧠ANSWER ✔✔1. agarose (polysaccharide)
2. polyacrylamide (neurotoxin)
Gel Electrophoresis: Sample possiblitiies - 🧠ANSWER ✔✔1. Eukaryotic genome
2. Bacterial genome
3. Viral genome
4. Plasmid
Digest with __ - 🧠ANSWER ✔✔EcoR1
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
1
, steps of Southern Blotting - 🧠ANSWER ✔✔1. Agarose gel electrophoresis of
DNA fragments
2. Denature DNA and blot (converts to ssDNA)
3. Southern Blot on filter
4. Block nonspecific DNA or protein then incubate with labeled probe
5. Photographic detection
6. Positive band "lights up"
Klenow fragments - 🧠ANSWER ✔✔large fragment of DNA polymerase, used to
extend primers
Stringency - 🧠ANSWER ✔✔Properties of hybridization conditions that dictate the
degree of base mismatch permitted between probe and DNA trage
Low stringency: Increase in number of mismatch (high background noise)
High stringency: Decrease in number of mismatch (low background noise) *high
temp, low salt
Gel filtration - 🧠ANSWER ✔✔Gel filtration chromatography uses
columns fi lled with porous resins that let in smaller
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
2
