Genes, chromosomes and mutations

Grade 7 Science Worksheet - Building Confidence

Circle the best answer.

1. 1.

   Ari fills in a zoom strip that goes from the biggest part to the smallest. Which part goes in the box?

   • Chromosome, a thread made of DNA
   • Protein, which a gene gives instructions for
   • Trait, such as the color of a flower
   • Gene, which holds the DNA inside it
2. 2.

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

   • Nucleus, home of the chromosomes
   • Protein, a chain made from instructions
   • DNA, which is bigger than a chromosome
   • Gene, which holds a whole chromosome
3. 3.

   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?

   • Chromosome, which is smaller than DNA
   • Trait, such as the shape of a seed
   • Gene, a short section of DNA
   • Protein, a smaller part of the nucleus
4. 4.

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

   • A change in the letters of DNA
   • A long thread of DNA in the nucleus
   • A DNA section that codes for a protein
   • A feature you can see, such as seed shape
5. 5.

   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 thread of DNA and protein in the nucleus
   • A change in the letters of DNA
   • A trait that both parents share
6. 6.

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

   • A harmful change in the DNA of a plant
   • A change in the DNA of a living thing
   • A change in DNA that gives a new trait
   • A change a living thing makes on purpose
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
   • White flowers, the trait itself
   • No working protein is made
   • A longer chromosome with extra genes
8. 8.

   Pia reads the chart. A letter in row 2 was changed. Which cell of row 2 holds the changed letter?

   • The Protein cell, since a protein is a chain of letters
   • The Gene cell, since a mutation is a change in DNA
   • The Trait cell, since traits are made of DNA
   • The Trait cell, since the flower color changed

9. 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

10. 9.

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

    • The fifth letter
    • No letter, since the copies match
    • The fourth letter
    • The sixth letter
11. 10.

    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, a mutation is a chance change in DNA
    • No, the change happened outside the cell
    • Yes, a plant changes DNA when it needs to