Biology
Are the following statements true or false? Give reason in support of your answer.
Photosynthesis is considered as a process supporting all life on earth.
Answer
True.
Reason — Chlorophyll is the green colouring matter found in plants. It is contained in microscopic cell organelles called chloroplasts. Chlorophyll is the foundation site for the photosynthesis in green plants. The initiation of photosynthesis takes place when the chlorophyll molecule traps the light energy. The light energy is then converted into chemical energy in the form of glucose using carbon dioxide (CO2) from the atmosphere, and water (H2O) from the soil. All other organisms, directly or indirectly depend on this food for their survival. The starting point of any food chain is always a plant. If green plants were to suddenly disappear, then so would virtually all life on Earth. Thus, we can say that all life owes its existence to chlorophyll.
Related Questions
A potted plant with variegated leaves was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours and then placed in bright sunlight for a few hours. Observe the diagram and answer the questions:
(a) What aspect of photosynthesis is being tested in the above diagram?
(b) Why was the plant placed in the dark before beginning the experiment?
(c) Write a balanced chemical equation to represent the process of photosynthesis.
(d) What will be the result of starch test when performed on leaf A shown in the diagram?
(e) Draw a neat and labelled diagram of a chloroplast.
Given below is the diagram of an experimental set-up:
a. What is the objective of this experiment?
b. Will it work satisfactorily? Given reason.
c. What alteration (s) will you make in it for obtaining expected result?
d. Would you take any step before starting the experiment? Describe this step and explain its necessity.
Draw a neat diagram of the stomatal apparatus found in the epidermis of leaves and label the Stoma, Guard cells, Chloroplast, Epidermal cells, Cell wall and Nucleus.
Given below is the diagram of an experimental set-up (final stage). Study the same and answer the following questions :
(a) What is the main aim of the experiment?
(b) Oxygen gas shown in the experiment is released from which of the raw materials ?
(c) How would you confirm the presence of oxygen gas?
(d) Name the chemical substance which can be added in water to enhance the process/rate of release of oxygen gas.
(e) Draw a neat and labelled diagram of the same experiment for its initial stage.