The correct answer is A. Provides body tissues with oxygen
Explanation:
The respiratory system includes different organs such as the lungs, diaphragm, trachea, etc. that allow organisms especially animals to exchange gases that are necessary to survive. This mainly occurs as oxygen is taken from air or water in the case of fish and other aquatic animals and this provides the body tissues with oxygen that is necessary for multiple processes and at the same time it takes out the carbon dioxide through exhalation. Considering this, it can be concluded the respiratory system provides body tissues with oxygen.
With less oxygen there is less carbon dioxide being produced for the plants so photosynthesis decreases.
Answer: B
Explanation: Multiple different combinations of bases (A, G, C, T) can code for the same amino acid. This means that there are more possible combinations of the bases than there are amino acids. There are 20 amino acids and the four bases can have up to 64 different codon combinations.
D. 5
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