Match samples with a DNA fingerprint

Grade 9 Science Worksheet - Challenge Me

Circle the best answer.

1. Read this first

   Use this

   Model gel (not to scale; model data). Wells at the top, next to the negative (-) end. The positive (+) end is at the bottom. Ladder lane, top to bottom: 1000, 500, 250, 100 bp. Seed packet sample, bands: 800, 450, 300 bp. Plant A, bands: 800, 450, 300 bp. Plant B, bands: 700, 450, 250 bp. Plant C, bands: 800, 350, 300 bp.

2. 1.

   A classmate says Plant C matches the seed packet because two of three bands line up. Which reply fits, by Esme's reading?

   • Correct; two of three bands is close enough to call the two plants a match
   • Correct; matching plants share most bands, not every one
   • No; Plant C is not a tomato, so it cannot be compared at all
   • No; its 350 bp band differs, and a match needs every band to line up
4. 2.

   A student says the puppy's pattern should match its mother's exactly. Which reply fits OpenStax, by Jun's reading?

   • Correct; a puppy inherits the whole of its DNA from its mother's side of the family
   • No; it should match the father's pattern exactly
   • Correct; the father's DNA doesn't show up on the gel
   • No; it inherits from both parents, so some bands come from the father
5. 3.

   A student says the bands show genes for coat color and size. Which reply fits OpenStax, by Kira's reading?

   Use the picture in question 2.

   • No; they show the lengths of repeated stretches, often in non-coding DNA
   • No; they show the animal's proteins
   • Correct; bigger bands mean bigger animals
   • Correct; each band is one gene for a visible trait, such as coat color or size
6. 4.

   A new male, Z, has bands at 750, 450, 300 and 100 bp. Could Z be the puppy's father, by Luz's reading?

   Use the picture in question 2.

   • Yes; Z has both of the puppy's bands that the mother lacks
   • No; Z's 450 bp band is not in the puppy, so Z cannot be its father
   • No; Z shares no bands with the mother
   • Yes; Z has four bands, like the puppy
7. 5.

   Model gel (not to scale; model data). A second calf has bands at 1000, 800, 500 and 250 bp. Which bull could be its father, by Milo's reading?

   • Bull P
   • Neither bull
   • Both bulls
   • Bull Q
8. 6.

   In the dog gel, Male Y shares no bands with the puppy. What does that show, by Noah's reading?

   • Male Y can be ruled out as the father
   • Male Y is the puppy's mother
   • Nothing; bands do not come from parents
   • Male Y must be the father, since parents differ

9. Use this

   Model gel (not to scale; model data).

10. 7.

    Which evidence best rules out Tree 3 as Variety R, by Ren's reading?

    • It shares the 600 bp band with Variety R
    • Its 900 bp and 350 bp bands are not in Variety R's lane
    • It has the same number of bands as Variety R, three in each lane
    • Its leaves are a different shape
11. 8.

    A lab runs the calf twice and gets the same bands both times. Why does that help, by Tala's reading?

    • It shows the calf's genes for color
    • It shows the band pattern can be trusted
    • It shows big pieces run farther
    • It shows the calf has two fathers
12. 9.

    Which summary of a parent and offspring check fits, by Ari's reading?

    • An offspring shares no bands with its parents
    • Each offspring band must appear in one parent or the other
    • Each offspring band must appear in the mother's lane
    • The offspring must match one parent's pattern exactly
13. 10.

    Model gel (not to scale; model data). Which summary of what the bands are fits OpenStax, by Bo's reading?

    • Pieces of different lengths, from repeats that vary between individuals
    • Whole chromosomes, one per band
    • Genes for traits such as horn shape and coat color
    • Proteins, sorted by their charge