Fill in the blanks:
(a) Green plants are called _________________ since they synthesise their own food.
(b) The food synthesised by the plants is stored as _________________.
(c) In photosynthesis solar energy is captured by the pigment called ___________.
(d) During photosynthesis plants take in ______________________ and release __________________.
(a) Autotrophs
The mode of nutrition in which organisms make their food themselves from simple substances is called autotrophic nutrition. Hence, the plants that makes their own food are called autotrophs. There is a green pigment that are found in leaves of plants are called chlorophyll, which helps plants to capture sunlight and this energy is used to synthsis food from carbon dioxide and water.
(b) Starch
During photosynthesis oxygen gets released and the food is stored in leaves. Starch is a carbohydrate. The presence of starch in leaves indicates the occurrence of photosynthesis which can also be prooved by the iodine test.
(c) Chlorophyll
The green pigment present in the surface of the leaves is known as chlorophyll. It helps leaves to capture to the sunlight which can then be used to prepare food.
(d) CO2 , O2
During photosynthesis plants take CO2 and release O2 gas.
Popular Questions of Class 7 Science
- Q:-
Classify the changes involved in the following processes as physical or chemical changes:
(a) Photosynthesis
(b) Dissolving sugar in water
(c) Burning of coal
(d) Melting of wax
(e) Beating aluminium to make aluminium foil
(f ) Digestion of food - Q:-
Take three test-tubes. Fill æth of each with water. Label them A, B and C. Keep a snail in test-tube A, a water plant in test-tube B and in C, keep snail and plant both. Which test-tube would have the highest concentration of CO2?
- Q:-
Sketch the cross section of soil and label the various layers.
- Q:-
Why does an athlete breathe faster and deeper than usual after finishing the race?
- Q:-
Can we survive only on raw, leafy vegetables/grass? Discuss.
- Q:-
When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. What type of change is it? Explain.
- Q:-
An iron ball at 40°C is dropped in a mug containing water at 40°C. The heat will
(a) flow from iron ball to water.
(b) not flow from iron ball to water or from water to iron ball.
(c) flow from water to iron ball.
(d) increase the temperature of both. - Q:-
Stainless steel pans are usually provided with copper bottoms. The reason for this could be that
(a) copper bottom makes the pan more durable.
(b) such pans appear colourful.
(c) copper is a better conductor of heat than the stainless steel.
(d) copper is easier to clean than the stainless steel. - Q:-
Given below is a crossword puzzle based on this lesson. Use hints to fill in the blank spaces with letters that complete the words.
Down Across
(D) 1 : Thorough washing (A) 1 : Keeps warm
2 : Animal fibre 2 : Its leaves are eaten by silkworms
3 : Long thread like structure 3 : Hatches from egg of moth
- Q:-
One litre of water at 30°C is mixed with one litre of water at 50°C. The temperature of the mixture will be
(a) 80°C (b) more than 50°C but less than 80°C
(c) 20°C (d) between 30°C and 50°C
Recently Viewed Questions of Class 7 Science
- Q:-
Match items in Column I with those in Column II:
Column I Column II
(a) Bud (i) Maple
(b) Eyes (ii) Spirogyra
(c) Fragmentation (iii) Yeast
(d) Wings (iv) Bread mould
(e) Spores (v) Potato
(vi) Rose - Q:-
State whether the following statements are true or false. In case a statement is false, write the corrected statement in your notebook.
(a) Cutting a log of wood into pieces is a chemical change. (True/False)
(b) Formation of manure from leaves is a physical change. (True/False) (c) Iron pipes coated with zinc do not get rusted easily. (True/False)
(d) Iron and rust are the same substances. (True/False)
(e) Condensation of steam is not a chemical change. (True/False) - Q:-
How would you show that setting of curd is a chemical change?
- Q:-
In Fig. 17.15, the artist has forgotten to put the labels and directions on the arrows. Mark the directions on the arrows and label the diagram using the following labels:
clouds, rain, atmosphere, carbon dioxide, oxygen, plants, animals, soil, roots, water table.
- Q:-
The distance between two stations is 240 km. A train takes 4 hours to cover this distance. Calculate the speed of the train.
- Q:-
Explain how soil is formed.
- Q:-
Describe the process of neutralisation with the help of an example.
- Q:-
What are stomata? Give two functions of stomata.
- Q:-
Discuss why wearing more layers of clothing during winter keeps us warmer than wearing just one thick piece of clothing.
- Q:-
List the differences between clayey soil and sandy soil.
- NCERT Chapter