6. Plant nutrition

Question 1

Describe photosynthesis and equation

Answer 1

the process by which plants synthesise carbohydrates from raw materials using energy from light

carbon dioxide + water → glucose + oxygen in the presence of light and chlorophyll

6CO2 + 6H2O → C6H12O6 + 6O2

Question 2

Chlorophyll function

Answer 2

transfers energy from light into energy in chemicals, for the synthesis of carbohydrates

it is a green pigment that is found in chloroplasts

Question 3

use and storage of the carbohydrates made in photosynthesis

Answer 3

(a) starch as an energy store

(b) cellulose to build cell walls

(c) glucose used in respiration to provide energy

(d) sucrose for transport in the phloem

(e) nectar to attract insects for pollination

Question 4

nutrients needed by plants, function, deficiency disease

Answer 4

(a) nitrate ions for making amino acids
weak growth and yellowing of leaves

(b) magnesium ions for making chlorophyll
yellowing of leaves between the veins

Question 5

features of leaf

Answer 5

large surface area- for diffusion of carbon dioxide and absorption of a lot of light

thin- allows sunlight to penetrate to all cells to CO2 to diffuse in and O2 to diffuse out of leaf as quickly as possible.

these features are adaptations for photosynthesis

Question 6

structures in the leaf of a dicotyledonous plant

Answer 6

chloroplasts-

cuticle- protective layer on top of leaf that prevents water from evaporating

guard cells and stomata

upper and lower epidermis

palisade mesophyll

spongy mesophyll

air spaces

vascular bundles-
xylem- transport water into leaf for mesophyll cells to use in photosynthesis and for transpiration in stomata

phloem- transport sucrose and amino acid from source to sink around the plant