specialised plant cells

Question 1

leaf cells (palisade cells)

Answer 1

the main function of the leaf palisade cell is to photosynthesis, so they are packed with chloroplasts and are usually green

Question 2

epidermal cells

Answer 2

epidermal cells are found on the outside of the plant. they form an outer skin for the plant and protect the cells underneath. this explains why they need a flat shape and why they interlock like tiles. epidermal cells do not usually photosynthesise so they lack chloroplasts. light needs to pass through them, and they are usually transparent.

Question 3

Phloem cells

Answer 3

like xylem cells, phloem cells form like tubes. The tubes formed by phloem cells carry the food made in the leaves to all parts of the plant. phloem cells do not need to die to do this job. the ends of phloem cells have holes and look like sieves

Question 4

xylem cells

Answer 4

xylem cells form xylem tubes, which carry water and dissolved minerals up the plant and into the leaves. xylem tubes are made up of dead xylem cells joined end to end. when xylem cells die, the cell walls at each end of the cells dissolve, forming a long straw-like tube. they have thick walls with lots of cellulose to make the xylem tubes strong.

Question 5

root hair cells

Answer 5

root hair cells absorb water and dissolved minerals from the soil. they have small hairs, called root hairs, on their surface. this increases the surface area of the root hair cells so that they can soak up water more quickly

Question 6

guard cells

Answer 6

guard cells are kidney-shaped cells found on the surface of the leaves. they can change shape to either open or close the small hole between them. the small holes, called stomata (or stomates), allow substances such as carbon dioxide to enter the leaf. they also let water out of the leaf. most plants open their stomata at night; they close their stomata during the day (when it is hotter) to conserve water.