Skip to main content
Pearson+ LogoPearson+ Logo
Ch. 11 - DNA Replication and Recombination
Back
Previous problem
Next problem
All textbooksKlug 12th EditionCh. 11 - DNA Replication and RecombinationProblem 20

Chapter 11, Problem 20

Several temperature-sensitive mutant strains of E. coli display the following characteristics. Predict what enzyme or function is being affected by each mutation. Newly synthesized DNA contains many mismatched base pairs.

Verified Solution
Video duration:
1m
This video solution was recommended by our tutors as helpful for the problem above.
314
views
Was this helpful?

Video transcript

Hi everyone. Let's take a look at this practice problem together. How many base pairs would there be in a DNA molecule with 80,000 nucleotides. So this question is making sure that we understand the structure of D. N. A. So let's review that here. We have a very rough depiction of D. N. A. And D. N. A. Recall is a double helix made up of two strands and a nucleotide. Is this right here? So a nucleotide includes a phosphate group, a deoxyribonucleic group and then a nitrogenous space. And the nitrogenous base can be added in guanine timing or Cytisine. Now one strand is formed by connecting nucleotides with a phosphor di ester bond. And that here is the backbone of D. N. A. So each strand of D. N. A. Is connected via the nitrogenous bases. Now adenine always bonds with dining and citizen always bonds with guanine. So a base pair, One base pair equals two nucleotides. So we would take 80,000 nucleotides divide that by two. And that's going to give us 40,000 base pairs. Which will be option D. D. Is the correct answer. Alright everyone, I hope you found this helpful. And I'll see you soon for the next practice problem
Previous problemNext problem
Related Practice
Textbook Question
Why is DNA synthesis expected to be more complex in eukaryotes than in bacteria? How is DNA synthesis similar in the two types of organisms?
447
views
Textbook Question
Suppose that E. coli synthesizes DNA at a rate of 100,000 nucleotides per minute and takes 40 minutes to replicate its chromosome. (a) How many base pairs are present in the entire E. coli chromosome? (b) What is the physical length of the chromosome in its helical configuration—that is, what is the circumference of the chromosome if it were opened into a circle?
801
views
Textbook Question

DNA supercoiling, which occurs when coiling tension is generated ahead of the replication fork, is relieved by DNA gyrase. Supercoiling may also be involved in transcription regulation. Researchers discovered that enhancers operating over a long distance (2500 bp) are dependent on DNA supercoiling, while enhancers operating over shorter distances (110 bp) are not so dependent [Liu et al. (2001). Proc. Natl. Acad. Sci. USA 98:14,883–14,888]. Using a diagram, suggest a way in which supercoiling may positively influence enhancer activity over long distances.

523
views
Textbook Question
Several temperature-sensitive mutant strains of E. coli display the following characteristics. Predict what enzyme or function is being affected by each mutation. Okazaki fragments accumulate, and DNA synthesis is never completed.
330
views
Textbook Question
Several temperature-sensitive mutant strains of E. coli display the following characteristics. Predict what enzyme or function is being affected by each mutation. No initiation occurs.
258
views
Textbook Question
Several temperature-sensitive mutant strains of E. coli display the following characteristics. Predict what enzyme or function is being affected by each mutation. Synthesis is very slow.
244
views