1. What is autotrophic nutrition?
Plants make food by themselves.
2. Describe the significance of plants as autotrophs.
They serve as producers to produce food source for other organisms that cannot produce food by photosynthesis.
3. List a number of major elements required by plants.
Nitrogen, phosphorus, potassium, magnesium, sulphur, calcium, iron.
4. List the trace that are required by the plants.
Copper, zinc, Boron/Cobalt
5. In plants, what is the major function of nitrogen?
Produce protein
6. In plants, what are the major functions of phosphorus?
(1) produce nucleic acid
(2) involves in some enzymatic reactions
7. In plants, what are the major functions of magnesium?
Make chlorophyll, it is part of chloroplast.
8. In plants, what are the major functions of potassium?
(1) promote photosynthesis and transport of materials
(2) involves in some enzymatic reactions
9. list the names of all the structures of a leaf.
Cuticle, upper epidermis, palisade mesophyll, spongy mesophyll, lower epidermis, vascular bundles, xylem, phloem, air space, stomata, guard cells.
10. Where do the plants carry out gas exchange?
(1) leaf (through the stomata)
(2) stem (through the lenticel)
(3) root (all over the surface of the epidermis)
11. Describe how gas exchange takes place in the leaf.
Gases go in:
(1) gas in the air outside diffuse into the air space through the stomata
(2) the gas dissolves into the water film on the surface of the mesophyll cells
(3) the gas diffuses directly into the cell
(4) and then diffuse to neighbouring cells.
12. What are structural adaptation of leaves for gas exchange?
(1) leaf is broad and flat
(2) thin
(3) lots of air space
(4) surface of the mesophyll cells is moist
(5) presence of stomata
(6) presence of guard cells to control the opening and closing of the stomata, adjusting the rate of gas exchange.
13. What are the features of palisade mesophyll and what is the major function of palisade mesophyll?
Cylindrical, closely packed, with large amount of chloroplasts.
Functions: carry out photosynthesis
14. What are the features of spongy mesophyll?
Irregular, with less chloroplasts
15. What is the factor affecting the rate of gas exchange?
Light intensity (affect the net intake and outgoing of certain gases)
16. What is compensation point?
It is the light intensity at which the rate of photosynthesis equals the rate of respiration.
17. At which light intensity will the plants have a net output of oxygen?
When the rate of photosynthesis is larger than the rate of respiration.