| Autotrophic nutrition | Heterotrophic nutrition |
| (i) Food is synthesised from simple inorganic raw materials such as CO2 and water. | (i) Food is obtained directly or indirectly from autotrophs. This food is broken down with the help of enzymes. |
| (ii) Presence of green pigment (chlorophyll) is necessary | (ii) No pigment is required in this type of nutrition. |
| (iii)Food is generally prepared during day time. | (iii) Food can be prepared at all times |
| (iv) All green plants and some bacteria have this type of nutrition. | (iv) All animals and fungi have this type of nutrition. |
The availability of oxygen is much less in aquatic environment than in terrestrial environment. Due to this, aquatic organisms need to work harder to obtain oxygen. Hence, rate of breathing in aquatic organisms is much faster than in terrestrial organisms.
The autotrophic mode of nutrition requires
(a) carbon dioxide and water.
(b) chlorophyll.
(c) sunlight.
(d) all of the above.
Ans: (d) all of the above.
Match Group (A) with Group (B)
|
Group (A) |
Group (B) |
| (a) Autotrophic nutrition | (i) Leech |
| (b) Heterotrophic nutrition | (ii) Paramecium |
| (c) Parasitic nutrition | (iii) Deer |
| (d) Digestion in food vacuoles | (iv) Green plant |
Ans. (a)-iv (b)-iii (c)-i (d)-ii
The following raw materials are required for photosynthesis:
The raw material CO2 enters from the atmosphere through stomata.
Water is absorbed from the soil by the plant roots.
Sunlight, an important component to manufacture food, is absorbed by the chlorophyll and other green parts of the plants.
Importance of soil for plant growth:
(a) Soil provides the base on which a plant can grow.
(b) Soil serves as reservoir of water for plants.
(c) Soil serves as reservoir of different minerals which are essential for growth of plants.
(d) Soil contains many organic materials which provide nutrients to plants.