Science 7 · Unit 1: Cells · Cambridge Lower Secondary Science Stage 7

Questions

1. 1. Which part of a microscope holds the slide?

   • stage
   • fine focusing knob
   • eyepiece
   • mirror
   Check

2. 2. Which part of a microscope do you look through?

   • mirror
   • stage
   • eyepiece
   • objective lens
   Check

3. 3. What is the job of the mirror under the stage?

   • to hold the slide still
   • to make the cells look bigger
   • to reflect light up through the slide
   • to let you see your own eye
   Check

4. 4. A microscope has a low-power, a medium-power and a high-power objective lens. Which one should you use first?

   • any of them: it makes no difference
   • medium-power
   • low-power
   • high-power
   Check

5. 5. Which knob do you use for the first, big focusing movements?

   • coarse focusing knob
   • the stage clip
   • fine focusing knob
   • the mirror
   Check

6. 6. Zara cannot see the cells on her slide. Which could be the reason?

   • The eyepiece is too clean.
   • She is using the low-power objective lens.
   • The cells are too big to see.
   • The microscope is not focused on the slide.
   Check

7. 7. Zara cannot see the cells. Which could also be the reason?

   • The slide is on the stage.
   • The mirror is reflecting light up through the slide.
   • The cells are animal cells.
   • The part of the slide with cells on it is not under the objective lens.
   Check

8. 8. Zara still cannot see the cells. Which is a third possible reason?

   • The cells on the slide are animal cells.
   • Not enough light is reaching the slide.
   • The slide is on the stage.
   • She is looking down the eyepiece.
   Check

9. 9. What is the best advice for Zara to see the cells on her slide?

   • Take the slide off the stage and look again.
   • Turn the mirror away from the light.
   • Put the cells in the centre of the stage, start with the low-power lens and focus with the coarse knob.
   • Start with the high-power lens and turn the coarse knob quickly.
   Check

10. 10. Which list shows the parts that an animal cell has?

    • nucleus, cell wall, cytoplasm, chloroplasts
    • cell wall, cell membrane, mitochondria, nucleus
    • cell membrane, sap vacuole, nucleus, cytoplasm
    • nucleus, cytoplasm, cell membrane, mitochondria
    Check

11. 11. True or false: animal cells have mitochondria.

    • True
    • False
    Check

12. 12. A student puts some cheek cells on a slide and adds a drop of blue stain. Why add the stain?

    • to make the cells bigger
    • to kill any germs on the slide
    • to stick the cells to the slide
    • to make the parts of the cells easier to see
    Check

13. 13. Why does an animal cell not have a fixed shape like a plant cell?

    • It has no cell wall.
    • It is always much bigger.
    • It has no nucleus.
    • It has no cell membrane.
    Check

14. 14. Why do animal cells not have chloroplasts?

    • Animal cells are too small for chloroplasts.
    • Animals live in the dark.
    • Animals get their food by eating; they do not make it by photosynthesis.
    • Chloroplasts are only found in roots.
    Check

15. 15. A group builds a picture of a plant cell. Which pieces must they remove to change it into an animal cell?

    • the cell membrane and the mitochondria
    • the nucleus and the cell membrane
    • the nucleus and the cytoplasm
    • the cell wall, the chloroplasts and the sap vacuole
    Check