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प्रश्न
Respiration requires O2. How did the first cells on the earth manage to survive in an atmosphere that lacked O2?
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उत्तर
During the process of respiration, oxygen is utilised, and carbon dioxide, water and energy are released as products. The combustion reaction requires oxygen. But some cells live where oxygen may or may not be available. There are sufficient reasons to believe that the first cells on this planet lived in an atmosphere that lacked oxygen. Even among present-day living organisms, we know of several that are adapted to anaerobic conditions.
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संबंधित प्रश्न
What are respiratory substrates?
Name the most common respiratory substrate.
What happens to the energy liberated during respiration?
Glycolysis is a process ___________.
One same common function is performed by?
Do the plants respire all day and all night or only at night?
Name the following:
Energy currency of cell.
Name the following:
Oxidative breakdown of carbohydrates to release energy.
Name the following:
An organism which respires throughout life anaerobically.
Name the following:
Aerobic respiration requires_________ .
Why is it usually difficult to demonstrate respiration in green plants?
How is tilling of the soil useful for the crops growing in it?
Fill in the blank :
_________ are the openings found on older stems.
Fill in the blank :
Glycolysis occurs in the _______of the cells.
Fill in the blank:
_____________ is a respiratory substrate
Fill in the blank:
_____________ is a chemical which absorbs oxygen of the air.
How do the following structures help in respiration in plants?
Stomata _____________
The following diagram refers to an apparatus which is used to demonstrate a physiological process:
Define the biological process shown in the experiment.
Complete the following statement by choosing the correct alternative out of those given below.
Every living cell of the plant
Name the following:
The process of living beings which is concerned with the release of energy for use in the body.
The roots of a plant take up oxygen from the ______ trapped between the ______ particles.
Observe the figure carefully and answer the following questions.
- In which jar, will the amount of CO2 be the highest and why?
- In which jar, will the amount of CO2 be the lowest and why?
A food stall owner was preparing dough for making bhaturas. He added a pinch of yeast and sugar to the dough and left it in a warm place. After few hours, the dough had risen. There was a sour smell too.
Why did the dough rise?
A food stall owner was preparing dough for making bhaturas. He added a pinch of yeast and sugar to the dough and left it in a warm place. After few hours, the dough had risen. There was a sour smell too.
Why was sugar added to the dough?
A food stall owner was preparing dough for making bhaturas. He added a pinch of yeast and sugar to the dough and left it in a warm place. After few hours, the dough had risen. There was a sour smell too.
What would have happened if the dough was kept in the refrigerator, soon after it was prepared?
If a person is feeling dizzy, glucose or fruit juice is given immediately but not a cheese sandwich Explain.
It is known that red muscle fibres in animals can work for longer periods of time continuously. How is this possible?
RuBP carboxylase, PEP carboxylase, Pyruvate dehydrogenase, ATPase, cytochrome oxidase, Hexokinase, Lactate dehydrogenase.
Select/choose enzymes from the list above which are involved in
- Photosynthesis
- Respiration
- Both in photosynthesis and respiration
How does a tree trunk exchange gases with the environment although it lacks stomata?
