Measuring photosynthesis via the production of oxygen. Oxygen can be measured by counting bubbles evolved from pondweed, or by using the Audus apparatus to measure the amount of gas evolved over a period of time.
Explanation:
Option D is the correct option.
An organism that cannot make its own food is called a heterotroph. All animals and species of fungi, along with some types of bacteria, are heterotrophs.
<span>During nitrification, ammonia is changed back into nitrate.</span>
Nitrification is a three-step process of oxidation of ammonia. It is an aerobic process performed by small groups of autotrophic bacteria (<span>Nitrosomonas,
Nitrobacter</span>).
First step- ammonia to hydroxylamine,
Second step-hydroxylamine to nitrite,
Third step-nitrite to nitrate.
Nitrification together with ammonification is part of a nitrogen cycle.
<span>The circulatory system is vital in the exchange of oxygen with the cells in the animal's body because there is no living creature that can survive without oxygen, it keeps the body active.
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