<span>..has evaporated from all the water sources around the world (streams, rivers, ponds, seas, oceans etc).
It is am established fact that the quantity of water present on the Earth has remained constant from the beginning of time. At any given point in time it may exist in one of its three forms i.e.ice, water or water vapor but there is no variation in its total quantity (hydrological cycle).</span>
Answer: A. plants produce oxygen during photosynthesis and they also need oxygen from the air for cellular respiration.
In the process of photosynthesis the plants in the presence of sunlight, water and carbon dioxide produces a carbohydrates as food and oxygen is liberated into the atmosphere. The process of photosynthesis takes place in day and plants avail oxygen from the roots and leaves for respiration. The food produced is broken down into carbon dioxide and water with the release of energy in the presence of oxygen during cellular respiration. Plants produce oxygen as a byproduct of photosynthesis and use oxygen for cellular respiration.
On the basis of the above information, A. plants produce oxygen during photosynthesis and they also need oxygen from the air for cellular respiration is the correct statement that describes the relationship between plants and oxygen.
Answer: An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.
Explanation:
hope this helps!!