One parent or two: how living things reproduce

Grade 7 Science Worksheet - Challenge Me

Circle the best answer.

2. 1.

   Ari’s class reads the chart and the table. Which claim and reason fit what the data show?

   • Bed S had more plants growing well in Year 2, because its plants differ in their genes
   • Bed R had fewer plants growing well in Year 2, because pieces of one plant need a partner plant
   • Bed S had more plants growing well in Year 2, because its plants copy one parent
   • Bed R had more plants growing well in Year 2, because copies handle any change
3. 2.

   Bo reads the same chart and table. Which line explains why Bed R went from 8 plants growing well to 0?

   Use the picture in question 1.

   • Bed R plants share the same genes, so the dry weather affected them alike
   • Bed R plants had one parent, so they could not grow well without a partner plant
   • Each Bed R plant changed its own genes once the weather turned dry
   • Bed S had more plants growing well in Year 1, so it did better in Year 2
4. 3.

   In Year 3 the weather turns very cold. Esme uses the chart and the table to predict. Which prediction fits best?

   Use the picture in question 1.

   • Bed R plants will cope, since copies of one parent handle change well
   • Bed R plants will cope better, since pieces of one plant adjust their genes
   • Some Bed S plants may cope, but the Bed R plants will react in the same way
   • Bed S plants will react alike, since seeds copy their parents
5. 4.

   Kira reads that some plants make seeds without fertilization (egg and sperm cells joining). The seedlings match the parent plant’s genes. Which line explains this?

   • No egg and sperm cells joined, so the seedlings have only the parent’s genes
   • Egg and sperm cells joined, but the genes stayed the same in each seed
   • A second parent gave genes that happen to match the first
   • The seedlings changed their genes to look like the parent
6. 5.

   Luz reads that an iris spreads by underground stems called rhizomes and also makes flowers that form seeds. Which statement fits both ways of reproducing?

   • Rhizomes give a new mix of genes; seeds give copies of the plant
   • Rhizomes give copies of the plant; seeds give a new mix of genes
   • Both give copies, since each starts from one plant
   • Rhizomes need a partner plant; seeds come from one plant
7. 6.

   Milo says the chart and the table prove that plants grown from pieces of one parent do well in any weather. Which response finds the flaw?

   • All three years were mild, so the data cannot show a harsh year
   • Copies of one parent cope with any weather, so the claim is correct
   • Pieces of one parent need a partner plant, so the bed cannot be trusted
   • Pieces of one parent change their genes each year, so the data cannot be trusted
8. 7.

   Pia says sexual reproduction gives better results than asexual reproduction in every year. Which response uses the chart and the table to find the flaw?

   • Bed R is a flawed test, since pieces of one plant need a partner
   • In Year 2 Bed S had 3 plants growing well, so the claim fits the whole table
   • In Year 1 both beds had 8 plants growing well, so Bed S was not better then
   • Bed S is a flawed test, since its seeds are copies of one parent
9. 8.

   Ren wants new daffodils with the same genes as a favorite daffodil plant. Which plan and reason fit best?

   • Plant seeds from two plants, because the mix will match the favorite
   • Plant bulbs from it, because a bulb needs a partner plant’s genes
   • Plant seeds from it, because seeds are copies of one parent
   • Plant bulbs from it, because bulbs make copies of one parent
10. 9.

    Tala plans a plant bed in a field where the weather changes from year to year. Which plan and reason fit best?

    • Plant pieces of one parent, because copies suit any weather
    • Plant pieces of one parent, because the copies will change to suit each year
    • Plant seeds from two parents, because varied plants may include some that suit each year
    • Plant seeds, because seeds are exact copies of one parent
11. 10.

    Zee compares bright, scented flowers with bird song in spring. Which statement and reason fit best?

    • The flowers alone help reproduction, because song and nests are for shelter
    • Both help asexual reproduction, because each lets one parent copy itself
    • Both help sexual reproduction, because one draws pollinators and the other a partner
    • Both help sexual reproduction, because the flowers draw a partner and the song draws pollinators