6- plant nutrition

Question 1

photosynthesis

Answer 1

The process by which plants make carbohydrates from

raw materials using light energy.

Question 2

inorganic materials

Answer 2

water, CO2, minerals

Question 3

organic materials

Answer 3

proteins, vitamins, carbohydrates, lipids

Question 4

epidermis

Answer 4

one cell thick layer, has no chloroplast. It protects the inner cell layers of the leaf.

Question 5

cuticle

Answer 5

waxy material on the upper epidermis, it helps to stop water evaporation.

Question 6

palisade mesophyll

Answer 6

the cells are close to the top of the leaf, elongated, packed and contain chloroplasts to make photosynthesis.

Question 7

spongy mesophyll

Answer 7

round cells, have chloroplast, quite loosely, with large air spaces between them to allow diffusion of gases and water vapor.

Question 8

vascular bundle

Answer 8

[xylem & phloem], found in the mesophyll layer, have vessels to carry water & sucrose.

Question 9

stomata

Answer 9

tiny holes found in the lower epidermis. They are surrounded by two guard cells that help to open &
close the stoma for gas exchange.

Question 10

leaf adaptation for photosynthesis

Answer 10

1.Leaf is wide, to expose large surface area to
sunlight and air.
2.Leaf is thin, so faster diffusion for gases into
and out of the leaf.
3.Epidermis has no chloroplast, to allow sunlight
to reach mesophyll layer.
4.Palisade cells arranged end to end to trap
more sunlight for more photosynthesis.
5.Air spaces in spongy mesophyll, to allow gases
to diffuse in & out of the cells.
6.Stomata in lower epidermis: to allow gas
exchange.
7.Xylem vessels: to carry water to the leaf cells.
8.Phloem vessels: to carry sucrose away from
the leaf

Question 11

uses of glucose

Answer 11

1. energy, as it is broken down by respiration.
2. Stored as starch, in the leaf, roots and seeds.
3. Used to make proteins & other organic substances.
4. Converted to sucrose to be transported in the plant, .

Question 12

whys is glucose converted into sucrose for transport

Answer 12

sucrose is less reactive and water soluble

Question 13

function of nitrates/ ammonuim ions in plants

Answer 13

• make proteins

deficiency: weak growth, yellow leaves`

Question 14

function of magnesuim ions in plants

Answer 14

• make chlorophyll

deficiency: yellowing between the veins of the leaves

Question 15

limiting factors of plants

Answer 15

sunlight, CO2, temperature

Question 16

adnvantages of growing crops in glasshouse

Answer 16

light intensity, carbon dioxide concentration and

temperature can be controlled, so plants can photosynthesize as fast as possible.