Plant organs, xylem and phloem

Grade 9 Science Worksheet

Circle the best answer.

1. Read this first

   Use this

   Card (textbook facts), 3 rows. Columns: group, what it does. P, covers the outside of the leaf and controls gas exchange. Q, carries water, minerals and sugars through the leaf. R, is where photosynthesis happens and supports the veins.

2. 1.

   Ari reads a card about three groups of cells in a leaf. Which tissue is group Q?

   • Vascular tissue, which carries the three materials
   • Dermal tissue, which covers and protects the leaf
   • Ground tissue, which is the site of photosynthesis
   • Xylem, which carries the sugars to the leaf

3. Card (textbook facts)

   group	what it does
   P	forms the outer layer of the root and reaches out as root hairs
   Q	stores photosynthetic products such as starch
   R	carries water and minerals up toward the stem

4. 2.

   Bo reads a card about three groups of cells in a root. Which tissue is group P?

   • Ground tissue, which takes in food from the soil
   • Dermal tissue, which covers and protects the root
   • Phloem, which stores starch in the root
   • Vascular tissue, which carries water and minerals up

5. Map of a plant (model, not to scale)

   Five boxes, the soil, the roots, the stem, the leaf and the air. Arrows marked water and minerals run from the soil to the roots, from the roots to the stem and from the stem to the leaf; the last two run inside the xylem. An arrow marked water vapor runs from the leaf to the air, through the stomata. An arrow marked sugar runs from the leaf to the roots, inside the phloem.

6. 3.

   Kira reads a map. In the model, a leaf loses water vapor through its stomata. Where does the water that replaces it come from, and how does it arrive?

   • From the soil, up the xylem as the leaf pulls it
   • From the soil, pumped up by the cells of the stem
   • From the air, through stomata that exist to take in water
   • From the leaf's sugar, down the phloem to the stem

7. Map of a young plant (model, not to scale)

   Four boxes, the growing shoot tip, the top leaf, a lower leaf and the roots. An arrow marked sugar runs from the top leaf to the growing shoot tip. An arrow marked sugar runs from the lower leaf to the roots. Both sugar arrows run inside the phloem.

8. 4.

   Luz reads a map of a young plant. The top leaf makes sugar in the light. Where does its sugar usually go?

   • Up to the shoot tip, because the xylem carries sugar up
   • Nowhere, because the top leaf keeps the sugar it makes
   • Up to the growing shoot tip, the nearest sink
   • Down to the roots, because phloem carries sugar down
9. 5.

   “Model of a bean plant developing seeds (model, not to scale):” Pia reads a model of a bean plant that is developing seeds in pods. Which statement about the plant's sugar is correct?

   • Sugar from the roots flows to the developing seeds, which are sources
   • Sugar flows to the roots, because phloem carries sugar down to them
   • Sugar from the leaves flows to the developing seeds, which are sinks
   • Sugar from the soil flows to the developing seeds through the xylem
10. 6.

    The leaf is a source and the root is a sink. Tala reads a card of model data on the sap in one phloem tube. Which statement does the card support?

    • The sugar level falls from the leaf, a source, toward the root, a sink
    • The sugar level rises from the leaf toward the root
    • The sugar level is the same at the leaf and the root
    • The root has the most sugar in its sap, because roots make sugar
11. 7.

    Zee reads a graph of model data on dyed water in two celery stalks. Which statement does the graph support?

    • At minute 30 the dye was 6 cm higher in the stalk with leaves
    • At minute 30 the dye was 4.5 cm higher in the stalk with leaves
    • At minute 30 the dye was 4.5 cm higher in the stalk without leaves
    • The stalk with leaves moved the dye faster because its cells pump harder

12. Use this

    Investigation card (model data). Question: does the brightness of light change how much water a plant gives off? Changed: the brightness of the light on three matching bean plants (dark, dim or bright). Measured: the water that collects in a clear bag around the leaves of each plant, in mL, after 2 hours. Kept the same: the size of the plants, the bags and the room temperature. Results table: Light | Water collected (mL): dark | 1; dim | 3; bright | 7.

13. 8.

    Jun's class reads an investigation card about water given off by plants. What did the class change on purpose?

    • The water collected in the bag
    • The brightness of the light
    • The size of the bags
    • The temperature of the room

14. Use this

    Investigation card (model data). Question: does the number of leaves on a cut stem change how much water the stem takes up? Changed: the number of leaves on each cut stem (2, 4 or 6). Measured: the drop in the water level of each jar, in mL, after 1 day. Kept the same: the size of the stems, the jars, the starting water, a thin layer of oil on the water and the room. Results table: Leaves | Water level drop (mL): 2 | 3; 4 | 6; 6 | 9.

15. 9.

    Milo's class reads an investigation card about cut stems in jars. What did the class measure?

    • The starting amount of water
    • The number of leaves on each cut stem
    • The drop in the water level of each jar
    • The size of each jar

16. Use this

    Investigation card (model data). Question: does the lower surface of a leaf have more stomata than the upper surface? Changed: which surface of the leaf is counted, upper or lower. Measured: the number of stomata counted in one view under a microscope. Kept the same: the leaf, the size of the view and the microscope setting. Results table: Surface | Stomata counted: upper | 12; lower | 48.

17. 10.

    Ren's class reads an investigation card about stomata. Which change would make the test unfair?

    • Counting the lower surface in a larger view than the upper surface
    • Using one microscope setting for both surfaces
    • Writing both counts in the same results table
    • Counting the upper surface first and the lower surface second