Learning Materials
Features
Discover
Chapter 14: Problem 22
Which of the following does the enzyme primase synthesize? a. DNA primer b. Okazaki fragments c. phosphodiester linkage d. RNA primer
Over 30 million students worldwide already upgrade their learning with 91影视!
These are the key concepts you need to understand to accurately answer the question.
All the tools & learning materials you need for study success - in one app.
Get started for free
Describe the structure and complementary base pairing of DNA. a. DNA is made up of two strands that are twisted around each other to form a helix. Adenine pairs up with thymine and cytosine pairs with guanine. The two strands are anti-parallel in nature; that is, the 3鈥� end of one strand faces the 5鈥� end of other strand. Sugar, phosphate and nitrogenous bases contribute to the DNA structure. b. DNA is made up of two strands that are twisted around each other to form a helix. Adenine pairs up with cytosine and thymine pairs with guanine. The two strands are anti-parallel in nature; that is, the 3鈥� end of one strand faces the 5鈥� end of other strand. Sugar, phosphate and nitrogenous bases contribute to the DNA structure. c. DNA is made up of two strands that are twisted around each other to form a helix. Adenine pairs up with thymine and cytosine pairs with guanine. The two strands are parallel in nature; that is, the 3鈥� end of one strand faces the 3鈥� end of other strand. Sugar, phosphate and nitrogenous bases contribute to the DNA structure. d. DNA is made up of two strands that are twisted around each other to form a helix. Adenine pairs up with thymine and cytosine pairs with guanine. The two strands are anti-parallel in nature; that is, the 3鈥� end of one strand faces the 5鈥� end of other strand. Only sugar contributes to the DNA structure.
What is bacterial transformation? a. The transformation of a bacterium occurs during replication. b. It is the transformation of a bacterium into a pathogenic form. c. Transformation of bacteria involves changes in its chromosome. d. Transformation is a process in which external DNA is taken up by a cell, thereby changing morphology and physiology.
Which portion of a chromosome contains Okazaki fragments? a. helicase b. lagging strand c. leading strand d. primer
Explain why half of DNA is replicated in a discontinuous fashion. a. Replication of the lagging strand occurs in the direction away from the replication fork in short stretches of DNA, since access to the DNA is always from the 5鈥� end. This results in pieces of DNA being replicated in a discontinuous fashion. b. Replication of the leading strand occurs in the direction away from the replication fork in short stretches of DNA, since access to the DNA is always from the 5鈥� end. This results in pieces of DNA being replicated in a discontinuous fashion. c. Replication of the lagging strand occurs in the direction of the replication fork in short stretches of DNA, since access to the DNA is always from the 5鈥� end. This results in pieces of DNA being replicated in a discontinuous fashion. d. Replication of the lagging strand occurs in the direction away from the replication fork in short stretches of DNA, since access to the DNA is always from the 3鈥� end. This results in pieces of DNA being replicated in a discontinuous fashion.
The mitochondria of eukaryote cells contain their own circular DNA (mtDNA), consistent with their origin according to the theory of endosymbiosis. The mitochondrial genome is highly conserved in Eukarya. In humans, the 50 to 100 mitochondria in each of the cells in most tissues have 5 to 10 copies of the genome. Each has 37 genes that primarily encode proteins of the electron transport chain. Point mutations in which a single nucleotide is incorrectly placed is not repaired because the error-checking provided by DNA polymerase is not present in the mitochondria. The mutation rate for mtDNA is approximately 100 times higher than the mutation rate for nuclear DNA. The simultaneous existence of multiple alleles in each cell is likely, a condition called heteroplasmy. In mammals, sperm mitochondria are destroyed prior to fertilization. A. Explain how point mutations in mtDNA can result in a loss of function in critical cellular components such as cytochrome c yet not be lethal to the cell. B. Oocyte mitochondria are randomly segregated during meiosis, resulting in variation in the frequency of mtDNA mutations in offspring relative to the parent. Explain how a loss of function does not accumulate, lowering the metabolic performance from generation to generation. As described in the Evolution Connection in this chapter of the text, a fossil fingertip found in a Siberian cave revealed an evolutionary link between Neanderthals and Denisovans. Fossils from 28 individuals were located in the 鈥減it of bones,鈥� Sima de los Huesos, in Spain, thousands of miles from the Siberian cave. In 2013, mtDNA from a femur of one of these individuals was compared with mtDNA of Denisovans, Neanderthals, and modern humans. It was found that the Sima fossil shared many more alleles with Denisovans than with either Neanderthals or modern humans. In 2016, the same group of scientists who sequenced the mtDNA from the femur of one of the Sima fossils partially sequenced the DNA from that fossil, showing a clear connection to Neanderthals. C. Analyze these data to draw alternative conclusions regarding the relatedness of the three fossils and support each with evidence. D. Design a plan to differentiate or resolve these alternative conclusions.
What do you think about this solution?
We value your feedback to improve our textbook solutions.
Explanations 
Textbooks 
Flashcards 
91影视 AI 
Notes 
Study Plans 
Study Sets 
Find a degree 
Magazine