It is a <span>photosynthetic algae contained in reef building corals underwater</span>
Answer:
Radiocarbon dating involves finding the age of an ancient fossil by measuring its carbon-14 content. Carbon-14 (radiocarbon), is a naturally occurring radioactive isotope that forms when cosmic rays in the upper atmosphere strike nitrogen molecules, which then oxidize to become carbon dioxide.
Answer:
Explanation:
Both nitrate ions and ammonium ions can be taken up by plants (some prefer one to the other). These ions provide nitrogen for the plant to make its own amino acids for protein synthesis. Except in very high nitrogen soils, the addition of extra nitrate will stimulate plant growth.
Answer:
Option D, It is highly efficient, as oxygen-rich air enters the lungs even while a bird is exhaling
Explanation:
In the respiratory system of birds, air flows only in one direction due to which a bird is capable to take in oxygen even when it is exhaling. The air sacs allow only unidirectional flow of air, which is more fresh and contains high oxygen content. Even a bird’s lung are capable to store and pump air, when they are at stationary position.
Hence, option D is correct.