Table of contents

1. Introduction to Genetics51m
2. Mendel's Laws of Inheritance3h 37m
3. Extensions to Mendelian Inheritance2h 41m
4. Genetic Mapping and Linkage2h 28m
5. Genetics of Bacteria and Viruses1h 21m
6. Chromosomal Variation1h 48m
7. DNA and Chromosome Structure56m
8. DNA Replication1h 10m
9. Mitosis and Meiosis1h 34m
10. Transcription1h 0m
11. Translation58m
12. Gene Regulation in Prokaryotes1h 19m
13. Gene Regulation in Eukaryotes44m
14. Genetic Control of Development44m
15. Genomes and Genomics1h 50m
16. Transposable Elements47m
17. Mutation, Repair, and Recombination1h 6m
18. Molecular Genetic Tools19m
- Genetic Cloning
  9m
- Methods for Analyzing DNA
  9m
19. Cancer Genetics29m
- Overview of Cancer
  21m
- Cancer Mutations
  7m
20. Quantitative Genetics1h 26m
21. Population Genetics50m
- Hardy Weinberg
  19m
- Allelic Frequency Changes
  31m
22. Evolutionary Genetics29m

7. DNA and Chromosome Structure

DNA Structure

Genetics

7. DNA and Chromosome Structure

DNA Structure

Previous problemNext problem

Struggling with Genetics?

Join thousands of students who trust us to help them ace their exams!Watch the first video

Multiple Choice

Which of the following best describes the key structural features of a DNA molecule?

A double helix composed of two antiparallel strands held together by complementary base pairing

A linear chain of amino acids joined by peptide bonds

A single-stranded molecule with ribose sugar and uracil bases

A triple helix structure with identical parallel strands

Previous problemNext problem

Verified step by step guidance

Step 1: Understand the basic structure of DNA. DNA is composed of two long strands forming a double helix.

Step 2: Recognize that the two strands run in opposite directions, which is described as antiparallel orientation.

Step 3: Know that the strands are held together by complementary base pairing, where adenine pairs with thymine and cytosine pairs with guanine.

Step 4: Differentiate DNA from other molecules: amino acids joined by peptide bonds form proteins, not DNA; RNA is single-stranded and contains ribose sugar and uracil; and DNA does not form a triple helix with identical parallel strands.

Step 5: Conclude that the best description of DNA's key structural features is a double helix composed of two antiparallel strands held together by complementary base pairing.