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Boss quiz

10 questions on the whole topic. You get one try at each.

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  1. Which of these features is caused only by the environment?

    • Blood group
    • Natural eye colour
    • Height
    • A scar

  2. Which feature shows discontinuous variation?

    • Body mass
    • Blood group
    • Hand span
    • Height

  3. Where in a cell are the chromosomes?

    • In the cell wall
    • In the mitochondria
    • In the cell membrane
    • In the nucleus

  4. How many chromosomes does a human body cell have?

    • 2
    • 23
    • 46
    • 92

  5. What is a gene?

    • A whole chromosome
    • The nucleus of a cell
    • A kind of sex cell
    • A section of DNA that controls an inherited feature

  6. How much of a baby’s genetic information comes from its mother?

    • None of it
    • All of it
    • A quarter
    • Half

  7. Whose X-ray picture of DNA helped Watson and Crick to build their model?

    • Francis Crick
    • Rosalind Franklin
    • Charles Darwin
    • James Watson

  8. Soot turns tree bark dark. Why do dark moths become more common over the generations?

    • Light moths slowly turn into dark moths
    • The soot stains their wings
    • They decide to change colour
    • Birds find fewer of them, so more survive to breed

  9. What does it mean when a species is extinct?

    • No individuals of the species are left alive
    • It has moved to another country
    • Only a few are left alive
    • It lives only in zoos

  10. What is a gene bank for?

    • Storing money for scientists
    • Growing crops for supermarkets
    • Storing genetic material, such as seeds, so that it is not lost
    • Keeping rare animals as pets
Answers
  1. A scar. A scar comes from an injury. Blood group and eye colour are inherited. Height depends on both genes and the environment.
  2. Blood group. Blood group falls into separate groups. The other three can take any value in a range.
  3. In the nucleus. The nucleus holds the chromosomes, which carry the genes.
  4. 46. 46 chromosomes, which is 23 pairs.
  5. A section of DNA that controls an inherited feature. A chromosome is a long thread of DNA. A gene is a short section of it.
  6. Half. Half comes from the mother, in the egg. Half comes from the father, in the sperm.
  7. Rosalind Franklin. Photo 51, from Franklin’s laboratory, showed that DNA is a helix.
  8. Birds find fewer of them, so more survive to breed. Dark moths are harder to see on dark bark. More of them survive, breed and pass on their colour.
  9. No individuals of the species are left alive. Extinct means that every member of the species has died.
  10. Storing genetic material, such as seeds, so that it is not lost. The store keeps the genes safe. If a species or a variety dies out, it may be possible to grow or breed it again.