/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 8 What is a purine? a. a double ... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 14: Problem 8

What is a purine? a. a double ring structure with a six-membered ring fused to a five-membered ring b. a single six-membered ring c. a six-membered ring d. three phosphates covalently bonded by phosphodiester bonds

Short Answer

Expert verified
Option (a) describes a purine.

Step by step solution

01

- Understanding Ring Structures

Purines and pyrimidines are the two types of nitrogenous bases in nucleic acids, distinguished by their ring structures.
02

- Identifying Purine Structure

Purines are composed of a double ring structure: one six-membered ring fused to a five-membered ring. This sets them apart from pyrimidines, which have only a single six-membered ring.
03

- Analyzing the Answer Choices

Option (a) describes a double ring structure with a six-membered ring fused to a five-membered ring, which matches the definition of a purine. The other options do not describe purines correctly.
04

- Conclusion

Thus, based on our analysis, the correct answer is option (a).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

nitrogenous bases
Nitrogenous bases are essential components of nucleic acids, such as DNA and RNA. These bases fall into two categories: purines and pyrimidines.
The primary function of nitrogenous bases is to store and transfer genetic information. They do this by pairing with each other to form the double helix structure of DNA.
When looking at nitrogenous bases, it's crucial to understand that they each have specific pairing rules. In DNA:
  • Adenine (a purine) pairs with Thymine (a pyrimidine)
  • Guanine (a purine) pairs with Cytosine (a pyrimidine)

In RNA, Thymine is replaced by Uracil as a pyrimidine, which pairs with Adenine. This precise pairing is what allows genetic information to be copied and transmitted accurately.
nucleic acids
Nucleic acids are large biomolecules essential for all known forms of life. They are composed of monomers called nucleotides.
Each nucleotide contains three components: a sugar molecule, a phosphate group, and a nitrogenous base. The sequence of these nucleotides forms the genetic code.
There are two main types of nucleic acids: DNA and RNA.
  • DNA (deoxyribonucleic acid) serves as the long-term storage of genetic information. Its double-stranded structure forms the iconic double helix.
  • RNA (ribonucleic acid) is usually single-stranded and plays various roles in expressing and translating genetic information stored in DNA.

Nucleic acids are crucial in various biological processes including transcription, translation, and replication. Their unique structures allow for the encoding, transmission, and expression of genetic information contained within a cell.
purines and pyrimidines
Purines and pyrimidines are the two main categories of nitrogenous bases found in nucleic acids. Each type has a distinct structure and specific pairing rules.
  • Purines: These include Adenine and Guanine. They are characterized by a double ring structure: one six-membered ring fused to a five-membered ring.
  • Pyrimidines: These include Cytosine, Thymine (in DNA), and Uracil (in RNA). They have a single six-membered ring structure.

The difference in ring structure between purines and pyrimidines is crucial for the formation of stable DNA and RNA molecules. The consistent pairing between a purine and a pyrimidine (A-T or A-U, and G-C) helps maintain the uniform width of the DNA double helix.
This structural difference also aids in various biological functions, such as enzyme recognition and the accurate transmission of genetic information.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Explain how the components of DNA fit together. a. DNA is composed of nucleotides, consisting of a 5 carbon sugar, a phosphate, and a nitrogenous base. DNA is a double helical structure in which complementary base pairing occurs. Adenine pairs with thymine and guanine pairs with cytosine. Adenine and thymine form two hydrogen bonds and cytosine and guanine form three hydrogen bonds. The two individual strands of DNA are held together by covalent bonds between the phosphate of one nucleotide and sugar of the next. The two strands run anti parallel to each other. b. DNA is composed of nucleotides, consisting of a 5 carbon sugar, a phosphate, and a nitrogenous base. DNA is a double helical structure in which complementary base pairing occurs. Adenine pairs with cytosine and guanine pairs with thymine. Adenine and cytosine form two hydrogen bonds and guanine and thymine form three hydrogen bonds. The two individual strands of DNA are held together by covalent bonds between the phosphate of one nucleotide and sugar of the next. The two strands run anti parallel to each other. c. DNA is composed of nucleotides, consisting of a 5 carbon sugar, a phosphate, and a nitrogenous base. DNA is a double helical structure in which complementary base pairing occurs. Adenine pairs with cytosine and guanine pairs with thymine. Adenine and cytosine form three hydrogen bonds and guanine and thymine form two hydrogen bonds. The two individual strands of DNA are held together by covalent bonds between the phosphate of one nucleotide and sugar of the next. The two strands run antiparallel to each other. d. DNA is composed of nucleotides, consisting of a 5 carbon sugar, a phosphate, and a nitrogenous base. DNA is a double helical structure in which complementary base pairing occurs. Adenine pairs with cytosine and guanine pairs with thymine. Adenine and cytosine form three hydrogen bonds and guanine and thymine form two hydrogen bonds. The two individual strands of DNA are held together by covalent bonds between the phosphate of one nucleotide and sugar of the next. The two strands run parallel to each other.

Explain how forensic scientists are able to use DNA analysis to identify individuals. a. Comparison of DNA from a known source or individual with analysis of the sequence of an unknown sample of DNA allows scientists to find out if both of them are similar or not. b. DNA from the unknown sample is sequenced and analyzed. The result of the analysis is then matched with any random population. The matching individual then helps in forensics. c. Comparison of DNA from a known source or individual with analysis of the sequence of bases in strands of an unknown sample of RNA allows scientists to find out if both of them are similar or not. d. Comparison of DNA from a known source or individual with analysis of the sugars and phosphates in strands of an unknown sample of DNA allows scientists to find out if both of them are similar or not.

Provide a brief summary of the Sanger sequencing method. a. Frederick Sanger鈥檚 sequencing is a chain termination method that is used to generate DNA fragments that terminate at different points using dye-labeled dideoxynucleotides. DNA is separated by electrophoresis on the basis of size. The DNA sequence can be read out on an electropherogram generated by a laser scanner. b. Frederick Sanger鈥檚 sequencing is a chain elongation method that is used to generate DNA fragments that elongate at different points using dye-labeled dideoxynucleotides. DNA is separated by electrophoresis on the basis of size. The DNA sequence can be read out on an electropherogram generated by a laser scanner. c. Frederick Sanger鈥檚 sequencing is a chain termination method that is used to generate DNA fragments that terminate at different points using dye-labeled dideoxynucleotides. DNA is joined together by electrophoresis on the basis of size. The DNA sequence can be read out on an electropherogram generated by a laser scanner. d. Frederick Sanger鈥檚 sequencing is a chain termination method that is used to generate DNA fragments that terminate at different points using dye-labeled dideoxynucleotides. DNA is separated by electrophoresis on the basis of size. The DNA sequence can be read out on an electropherogram generated by a magnetic scanner.

Who was the first person to isolate the material that came to be known as nucleic acids? a. Frederick Griffith b. Friedrich Miescher c. James Watson d. Oswald Avery

What are Okazaki fragments and how they are formed? a. Okazaki fragments are short stretches of DNA on the lagging strand, which is synthesized in the direction away from the replication fork. b. Okazaki fragments are long stretches of DNA on the lagging strand, which is synthesized in the direction of the replication fork. c. Okazaki fragments are long stretches of DNA on the leading strand, which is synthesized in the direction away from the replication fork. d. Okazaki fragments are short stretches of DNA on the leading strand, which is synthesized in the direction of the replication fork.
See all solutions

Recommended explanations on Biology Textbooks

Heredity

Read Explanation

Plant Biology

Read Explanation

Responding to Change

Read Explanation

Biological Processes

Read Explanation

Ecological Levels

Read Explanation

Bioenergetics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.