Carbohydrates, lipids, proteins and nucleic acids

Grade 7 Science Worksheet - Challenge Me

Circle the best answer.

2. 1.

   A molecule is built from glucose units and gives plant cell walls their strength. Which molecule is it, Ari?

   • Cellulose, a carbohydrate
   • Olive oil, a lipid
   • Keratin, a protein
   • Starch, a stored carbohydrate
3. 2.

   A molecule is built from nucleotides and kept in the nucleus. Which molecule is it, Bo?

   Use the picture in question 1.

   • An enzyme protein
   • DNA
   • Starch
   • A cell membrane lipid
4. 3.

   A molecule is built from glycerol and fatty acids and is liquid at room temperature. Which molecule is it, Esme?

   Use the picture in question 1.

   • A solid fat, a lipid
   • A protein
   • A plant oil, a lipid
   • Starch
5. 4.

   Which list holds only lipids, Kira?

   • Olive oil, oats, sunflower oil
   • Olive oil, canola oil, sunflower oil
   • Brown rice, canola oil, potatoes
   • Potatoes, oats, brown rice
6. 5.

   Ribosomes join amino acids in a set order to make a protein. Which molecule holds the instructions for that order, Milo?

   • Another protein, an enzyme
   • A lipid
   • Starch
   • DNA, a nucleic acid
7. 6.

   Chloroplasts make sugar from carbon dioxide and water. To store it, the plant joins many sugars into what, Noah?

   • Cell membranes
   • Amino acids, joined into protein
   • DNA
   • Starch, a carbohydrate
8. 7.

   MedlinePlus says two of these give the body energy. Which two, Pia?

   • Water and DNA
   • Fiber and water
   • Carbohydrates and fats
   • Fiber and nucleic acids
9. 8.

   Ren says protein comes from animal foods alone. Agree or disagree?

   • Agree: beans are just starch
   • Agree: plants have no protein
   • Disagree: soy and beans supply protein
   • Disagree: protein comes from plant oils instead
10. 9.

    Tala says DNA is a kind of protein. Agree or disagree?

    • Agree: DNA and enzymes are one thing
    • Disagree: DNA is a lipid
    • Agree: DNA is built from amino acids
    • Disagree: DNA is a nucleic acid
11. 10.

    Zee says fats and oils are built from amino acids. Agree or disagree?

    • Agree: oils are proteins
    • Disagree: they come from glycerol and fatty acids
    • Disagree: they are built from nucleotides
    • Agree: amino acids build fats too