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

11. Translation

Transfer RNA

Genetics

11. Translation

Transfer RNA

Previous problemNext problem

1:54 minutes

Problem 1a

Textbook Question

What experimentally derived information led to Holley's proposal of the two-dimensional cloverleaf model of tRNA?

Verified step by step guidance

Understand the context: The question is asking about the experimental evidence that led to Robert Holley's proposal of the two-dimensional cloverleaf model of tRNA. This model was a significant breakthrough in understanding the structure and function of transfer RNA (tRNA).

Review the role of tRNA: tRNA is a small RNA molecule that plays a critical role in translation by carrying amino acids to the ribosome and matching them to the codons on mRNA. Its structure is essential for its function.

Examine the experimental techniques: Holley's work involved sequencing the nucleotides of tRNA. He used techniques such as enzymatic digestion of tRNA into smaller fragments, followed by separation and identification of these fragments to determine the sequence of nucleotides.

Consider the structural insights: The sequencing data revealed conserved regions and complementary base-pairing within the tRNA molecule. This suggested the presence of secondary structures, such as stems and loops, which were key to the cloverleaf model.

Conclude with the cloverleaf model: Based on the experimental data, Holley proposed the two-dimensional cloverleaf model, which includes four arms (the acceptor stem, the D arm, the anticodon arm, and the TψC arm) and a central loop. This model explained how tRNA could fold into a functional structure for translation.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Play a video:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

tRNA Structure

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in translating the genetic code from mRNA into proteins. It has a characteristic cloverleaf structure, which allows it to carry specific amino acids to the ribosome during protein synthesis. Understanding the structure of tRNA is essential for grasping how it interacts with mRNA and ribosomes to facilitate translation.

Holley's Cloverleaf Model

The two-dimensional cloverleaf model of tRNA was proposed by Francis Crick and later refined by Robert Holley based on experimental data. This model illustrates how tRNA molecules fold into a specific shape that is essential for their function in protein synthesis. Holley's work involved analyzing the sequences and structures of tRNA, leading to insights into how these molecules recognize codons on mRNA.

Experimental Evidence

The proposal of the cloverleaf model was supported by various experimental techniques, including enzymatic digestion and chemical modification studies. These experiments provided evidence for the secondary structure of tRNA, revealing how specific regions of the molecule interact with amino acids and mRNA. Understanding the methods used to derive this information is crucial for appreciating the scientific process behind the model's development.