Skip to main content
Pearson+ LogoPearson+ Logo

Discovery of Transposable Elements quiz #1 Flashcards

Discovery of Transposable Elements quiz #1
Control buttons has been changed to "navigation" mode.
1/10
  • Transposons were discovered by which scientist?
    Transposons were discovered by Barbara McClintock while studying chromosomal breakage in maize (corn) in the 1940s and 1950s.
  • How can the presence of transposable elements within a cell increase genetic diversity?
    Transposable elements can move within the genome, inserting themselves into different genes and disrupting their function. This movement can create new mutations, alter gene expression, and lead to varied phenotypes, thereby increasing genetic diversity.
  • What chromosome in maize did Barbara McClintock observe breaking repeatedly at the same spot?
    Barbara McClintock observed chromosome 9 in maize breaking repeatedly at the same spot, which led her to investigate the underlying cause.
  • What is the difference between autonomous and non-autonomous transposable elements?
    Autonomous elements, like Ac, can move independently, while non-autonomous elements, like Ds, require the presence of an autonomous element to move.
  • Why was the Ac element difficult for McClintock to map in the genome?
    The Ac element was difficult to map because it kept appearing in new locations, suggesting it was moving around the genome.
  • How did McClintock use corn kernel color to study transposable elements?
    She observed unstable phenotypes in corn kernels, such as spots and swirls of color, which indicated the activity of transposable elements affecting the color gene.
  • What happens to the color gene in corn when the Ds element jumps into it?
    When the Ds element jumps into the color gene, it inactivates the gene, resulting in a white kernel.
  • How does the timing of Ds element movement affect the phenotype of corn kernels?
    The timing of Ds movement during kernel development determines the pattern and extent of color changes, leading to unique phenotypes in each kernel.
  • What did McClintock conclude about the relationship between Ac and Ds elements?
    She concluded that Ds could only move if Ac was present, demonstrating a dependency between the two elements.
  • Why are transposable elements considered important for genetic variability and evolution?
    Transposable elements can alter gene function and expression by moving within the genome, contributing to genetic variability and evolutionary change.