Molecular Biology: Meselson and Stahl (1959)
24 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Who demonstrated a direct link between chromosomes and hereditable factors in 1911?

  • James Watson
  • Charles Darwin
  • Frederick Griffith
  • Thomas Morgan (correct)
  • What did Thomas Morgan propose based on his observations of white eyes in males?

  • That white eyes are a result of random mutation
  • That the white eye trait is linked to a specific gene
  • That chromosomes determine eye color
  • That sex chromosomes determine the white eye trait (correct)
  • What is the term used to describe the concept discovered by Frederick Griffith in 1928?

  • The molecular model
  • The transforming principle (correct)
  • The genetic code
  • The central dogma
  • What type of molecule is likely to be involved in the transforming principle?

    <p>DNA</p> Signup and view all the answers

    What is the role of chromosomes according to Thomas Morgan's work?

    <p>To carry genetic information</p> Signup and view all the answers

    What is a key concept related to chromosomes and hereditary traits?

    <p>Sex-linked traits</p> Signup and view all the answers

    What is the significance of Thomas Morgan's work in the context of molecular biology?

    <p>It showed the link between chromosomes and hereditary traits</p> Signup and view all the answers

    What is the underlying idea behind Thomas Morgan's work and Frederick Griffith's discovery?

    <p>Genetic information is carried on chromosomes</p> Signup and view all the answers

    What is the name of the replication model proposed by Meselson and Stahl in 1959?

    <p>Semi-conservative replication</p> Signup and view all the answers

    Who contributed to the discovery of the genetic code in 1965?

    <p>All of the above</p> Signup and view all the answers

    What was the significance of Fred Sanger's work in 1977?

    <p>He developed a method for DNA sequencing</p> Signup and view all the answers

    What is the relationship between genome size and organism complexity in eukaryotes?

    <p>There is a remarkable lack of correspondence between the two</p> Signup and view all the answers

    Who sequenced the human genome in 2001?

    <p>Craig Venter</p> Signup and view all the answers

    What is the relationship between the number of protein-coding genes and organism complexity?

    <p>There is a remarkable lack of correspondence between the two</p> Signup and view all the answers

    Which of the following scientists did not contribute to the discovery of the genetic code?

    <p>Venter</p> Signup and view all the answers

    What was the significance of the work of Meselson and Stahl in 1959?

    <p>They provided evidence for the semi-conservative replication model of DNA</p> Signup and view all the answers

    Who is credited with the discovery of cells?

    <p>Robert Hooke</p> Signup and view all the answers

    What is the fundamental theory of heredity according to Mendel's principles of inheritance?

    <p>Inheritance involves the passing of discrete units of inheritance</p> Signup and view all the answers

    What is the process called during which the inherited factors that determine traits are separated into reproductive cells?

    <p>Meiosis</p> Signup and view all the answers

    What is the principle of independent assortment according to Mendel's principles of inheritance?

    <p>Units of inheritance located on different 'places' will be inherited independently of each other</p> Signup and view all the answers

    Who formulated the cell theory?

    <p>Matthias Schleiden and Theodor Schwann</p> Signup and view all the answers

    What is the third principle of the cell theory?

    <p>Cells can arise from pre-existing cells</p> Signup and view all the answers

    What is the basic unit of structure and organization in organisms according to the cell theory?

    <p>Cell</p> Signup and view all the answers

    Who is known for setting up the rules to understand heredity?

    <p>Gregor Mendel</p> Signup and view all the answers

    Study Notes

    Key Discoveries in Molecular Biology

    • Robert Hooke (1665) discovered cells, which were initially referred to as "monastic cells".
    • Matthias Schleiden and Theodor Schwann (1839) formulated the cell theory, which states that:
      • All living organisms are composed of one or more cells.
      • The cell is the basic unit of structure and organization in organisms.
      • Cells arise from pre-existing cells.

    Mendel's Principles of Inheritance

    • Gregor Mendel (1865) set up the rules to understand heredity (genetics) and established three principles:
      • The fundamental theory of heredity, which states that inheritance involves the passing of discrete units of inheritance (now known as genes) from parents to offspring.
      • The principle of segregation, which states that during reproduction, the inherited factors that determine traits are separated into reproductive cells by a process called meiosis and randomly reunite during fertilization.
      • The principle of independent assortment, which states that "units of inheritance" located on different "places" will be inherited independently of each other.
    • Thomas Morgan (1911) demonstrated a direct link between chromosomes and heritable factors, and showed that:
      • Some traits are sex-linked.
      • The white trait was probably carried on one of the sex chromosomes.
      • Other genes were probably carried on specific chromosomes as well.

    The Transforming Principle

    • Frederick Griffith (1928) discovered the "transforming principle", which involves the transfer of genetic information from one bacterium to another.

    Semi-Conservative Replication

    • Meselson and Stahl (1959) demonstrated semi-conservative replication, which is a key mechanism of DNA replication.

    The Genetic Code

    • Crick, Brenner, Barnett, and Watts-Tobin (1965) contributed to the discovery of the genetic code, which is the set of rules that dictates how genetic information is translated into proteins.
    • Marshall Nirenberg and Heinrich J. Matthaei also contributed to the discovery of the genetic code.

    DNA Sequencing

    • Fred Sanger (1977) developed a method for DNA sequencing, which allows for the determination of the order of nucleotide bases in a DNA molecule.
    • Craig Venter (2000) led the effort to sequence the Drosophila genome, and later (2001) led the effort to sequence the human genome.

    Genomes

    • There is a remarkable lack of correspondence between genome size and organism complexity, especially among eukaryotes.
    • There is also a lack of correspondence between the number of protein-coding genes and organism complexity.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    This quiz assesses your understanding of Meselson and Stahl's 1959 experiment on semi-conservative replication, a fundamental concept in molecular biology.

    Use Quizgecko on...
    Browser
    Browser