Question

In: Biology

Explain why, in any DNA molecule, the % adenine = % thymine, and the %cytosine =...

Explain why, in any DNA molecule, the % adenine = % thymine, and the %cytosine = % guanine.

Solutions

Expert Solution

Watson and Crick proposed that the DNA is made up of two strands that are twisted around each other to form a right-handed helix, called a double helix. Base-pairing takes place between a purine and pyrimidine: namely, A pairs with T, and G pairs with C. In other words, adenine and thymine are complementary base pairs, and cytosine and guanine are also complementary base pairs. This is the basis for Chargaff’s rule; because of their complementarity, there is as much adenine as thymine in a DNA molecule and as much guanine as cytosine. Adenine and thymine are connected by two hydrogen bonds, and cytosine and guanine are connected by three hydrogen bonds. The two strands are anti-parallel in nature; that is, one strand will have the 3′ carbon of the sugar in the “upward” position, whereas the other strand will have the 5′ carbon in the upward position. The diameter of the DNA double helix is uniform throughout because a purine (two rings) always pairs with a pyrimidine (one ring) and their combined lengths are always equal.

(Source: https://opentextbc.ca/biology/chapter/9-1-the-structure-of-dna/)


Related Solutions

1. Using 3 nucleotides, adenine, guanine, and cytosine, illustrate why the sequence in DNA is read...
1. Using 3 nucleotides, adenine, guanine, and cytosine, illustrate why the sequence in DNA is read from 5’--------?3’. Draw the structures of the linked nucleotides to illustrate your answer. 2. Draw the structure of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoinositol. Using the drawing, illustrate the difference between saturated and unsaturated fatty acids: 16:0 and 18:1, n-9. 3. Discuss how the structure of the cell membrane regulates the passage of material in and out of the cell. To answer this question, list and draw the components...
Explain why adenine is chemically Unable to pair with cytosine and why is guanine chemically unable...
Explain why adenine is chemically Unable to pair with cytosine and why is guanine chemically unable to pair with thymine.
In a DNA molecule, the base pair adenine and thymine is held together by two hydrogen bonds (see Fig. 16.5). Let’s model one of these hydrogen bonds as four point charges
In a DNA molecule, the base pair adenine and thymine is held together by two hydrogen bonds (see Fig. 16.5). Let’s model one of these hydrogen bonds as four point charges arranged along a straight line. Using the information in the figure, calculate the magnitude of the net electric force exerted by one base on the other.
11. Why do you think thymine is used in DNA and uracil used in RNA when...
11. Why do you think thymine is used in DNA and uracil used in RNA when the other three bases are the same in each?
Why are DNA proofreading enzymes necessary? A DNA molecule can be thought of as having 2...
Why are DNA proofreading enzymes necessary? A DNA molecule can be thought of as having 2 components, corresponding to the sides and rungs of a ladder. What are these 2 components? What class of molecule is telomerase? What does telomerase do? In which human cells is telomerase appropriately active? In what kinds of cells is telomerase inappropriately active?
1.) Cytosine makes up 20% of the nucleotides in a sample of DNA from an organism....
1.) Cytosine makes up 20% of the nucleotides in a sample of DNA from an organism. What percent of the nucleotides in this sample will be thymine? A. 20 B. 30 C. 40 D. 80 E. it cannot be determined from the information given 2.) Which one of the following statements about DNA is incorrect? A. The amount of A in double stranded DNA is equal to the amount of G. B. The amount of purines in double stranded DNA...
Diagram (draw) and describe the process of DNA replication. Include original molecule, the DNA molecule unzipping,...
Diagram (draw) and describe the process of DNA replication. Include original molecule, the DNA molecule unzipping, the addition of new nucleotides, and the products of replication.  
A molecule of DNA (deoxyribonucleic acid) is 2.31
A molecule of DNA (deoxyribonucleic acid) is 2.31
The experiments that clearly showed that DNA from every organism studied had an amount of adenine...
The experiments that clearly showed that DNA from every organism studied had an amount of adenine equal to the amount of thymine and a cytosine content equal to the content of guanine were conducted by: a.   E. M. Sutton. b.   Cohen and Boyer. c.   Hershey and Chase. d.   Erwin Chargaff. e.   Rosalind Franklin. A quiescent (non-dividing) human cell is most likely (or most correctly described as being) in: G1. S phase. G0 M phase. cytokinesis. Who utilized the process of...
Describe the structure of a water molecule. Explain WHY one end of the molecule is negative...
Describe the structure of a water molecule. Explain WHY one end of the molecule is negative with respect to the other end. Describe several (at least three) properties of water that make it so vital for living things. Focus on properties and examples that are relevant to the human body. What are enzymes and why are they important? Be sure to include the following in your answer: Compare and contrast hydrolytic enzymes to enzymes that do dehydration synthesis What does...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT