Plant Tissues (Leaf Structure)

Question 1

1. What is leaf vein?

Answer 1

Water and salts enter the leaf via the xylem. Sugar made by photosynthesis passes out of the leaf via the phloem.

Question 2

2. What is guard cells?

Answer 2

Stomata open and close in response to changing conditions, such as light intensity, humidity, and carbon dioxide concentration.

Question 3

3. What is lower epidermis?

Answer 3

The lower epidermis is a layer one cell thick, like the upper epidermis.

It contains pores called stomata (singular stoma). Each stoma is made is made up of a pair of guard cells.

The stomata allow gases and water vapour to diffuse in and out of the leaf.

Question 4

4. What is spongy mesophyll layer?

Answer 4

This layer consists of irregularly shaped cells with large air spaces between them and looks like a sponge when seen under a microscope.

The cells have fewer chloroplast than the palisade cells since the light intensity is less.

Question 5

5. What is palisade mesophyll layer?

Answer 5

Palisade cells have a cylindrical shape. This helps the light to penetrate into the leaf.

Chlorophyll is contained in chloroplasts. Palisade cells have more chloroplasts than other cells in the leaf.

The chloroplasts can move within the cell to regions where the light intensity is greatest.

Question 6

6. What is upper epidermis?

Answer 6

The upper epidermis is one cell thick and covers the leaf like a skin. The cuticle is a waxy layer which protects the leaf against disease organisms such as parasitic fungi.

The cuticle is waterproof and helps prevent water loss by evaporation.

Question 7

3. What is lower epidermis?

Answer 7

The lower epidermis is a layer one cell thick, like the upper epidermis.

Question 8

3. What does the lower epidermis contain?

Answer 8

It contains pores called stomata (singular stoma). Each stoma is made is made up of a pair of guard cells.

Question 9

3. What does the stomata allow?

Answer 9

The stomata allow gases and water vapour to diffuse in and out of the leaf.

Question 10

4. What does the spongy mesophyll layer consists of?

Answer 10

This layer consists of irregularly shaped cells with large air spaces between them and looks like a sponge when seen under a microscope.

Question 11

4. What do the cells have?

Answer 11

The cells have fewer chloroplast than the palisade cells since the light intensity is less.

Question 12

5. What kind of shape do palisade cells have?

Answer 12

Palisade cells have a cylindrical shape.

Question 13

5. What does it help?

Answer 13

This helps the light to penetrate into the leaf.

Question 14

5. What is chlorophyll contained in?

Answer 14

Chlorophyll is contained in chloroplasts.

Question 15

5. What cells have more chloroplasts than other cells in the leaf?

Answer 15

Palisade cells have more chloroplasts than other cells in the leaf.

Question 16

5. Where can the chloroplasts move within the cell?

Answer 16

The chloroplasts can move within the cell to regions where the light intensity is greatest.

Question 17

6. What is the upper epidermis?

Answer 17

The upper epidermis is one cell thick and covers the leaf like a skin.

Question 18

6. What is the function of the cuticle?/what is the cuticle?

Answer 18

The cuticle is a waxy layer which protects the leaf against disease organisms such as parasitic fungi.

The cuticle is waterproof and helps prevent water loss by evaporation.