Genes, chromosomes and mutations

Grade 7 Science Worksheet - Building Confidence

Circle the best answer.

1. 1.

   Bo fills in a different zoom strip, again from the biggest part to the smallest. Which part goes in the box?

   • Gene, which holds a whole chromosome
   • Nucleus, home of the chromosomes
   • DNA, which is bigger than a chromosome
   • Protein, a chain made from instructions
2. 2.

   biggest to smallest, not to scale. Esme fills in the last box of a zoom strip that goes from the biggest part to the smallest. Which part goes in the box?

   • Protein, a smaller part of the nucleus
   • Trait, such as the shape of a seed
   • Chromosome, which is smaller than DNA
   • Gene, a short section of DNA
3. 3.

   Jun reads a science word list. Which meaning goes with the word gene?

   • A DNA section that codes for a protein
   • A change in the letters of DNA
   • A feature you can see, such as seed shape
   • A long thread of DNA in the nucleus
4. 4.

   Kira reads the next word on the list. Which meaning goes with the word chromosome?

   • A short section of DNA that makes a protein
   • A change in the letters of DNA
   • A trait that both parents share
   • A thread of DNA and protein in the nucleus
5. 5.

   Luz reads the last word on the list. Which meaning goes with the word mutation?

   • A change a living thing makes on purpose
   • A change in the DNA of a living thing
   • A change in DNA that gives a new trait
   • A harmful change in the DNA of a plant
6. 6.

   Milo fills in the Trait box for the pea plant whose gene A has one changed letter. What goes in the box?

   • White flowers, since the protein is missing
   • Violet flowers, since the gene is still there
   • White flowers, since the plant chose the change
   • Pale violet flowers, a blend of the two colors
7. 7.

   Noah fills in the Protein box for the pea plant whose gene A has one changed letter. What goes in the box?

   • The same pigment-making protein as row 1
   • No working protein is made
   • White flowers, the trait itself
   • A longer chromosome with extra genes

8. Read this first

   Use the table

   Two strips of DNA letters (model data)

   Copy of a gene	DNA letters
   parent copy	A T G C C T A
   new copy	A T G C T T A

9. 8.

   Ren compares the two copies of a gene. Which letter of the new copy is different from the parent copy?

   • The sixth letter
   • The fourth letter
   • No letter, since the copies match
   • The fifth letter
10. 9.

    Tala says the plant changed the fifth letter on purpose because it needed a new trait. Which response is best?

    • Yes, the plant picks the helpful letters
    • No, the change happened outside the cell
    • Yes, a plant changes DNA when it needs to
    • No, a mutation is a chance change in DNA
11. 10.

    Zee asks if the card shows whether the changed letter is harmful, helpful or makes no difference. What is the answer?

    • Yes, a changed letter changes the trait
    • No, the effect depends on the protein
    • Yes, a changed letter is harmful
    • Yes, a changed letter helps the plant grow