Radioactive dating uses the concept of half life to determine the age of something.
The general idea is that elements exist naturally as a combination of isotopes. Some isotopes are stable while others decay radioactively. The half-life of a radioactive isotope is the time required to reduce the initial quantity of the isotope by 50% through the process of radioactive decay.
Carbon 14 dating works this way. A tree growing in the past would have an equilibrium mixture of C-12 and C-14 atoms in proportions consistent with living matter today. We know this value.
When that tree dies, it no longer accumulates new carbon atoms from carbon dioxide in the atmosphere (through photosynthesis). At this point, the proportion of C-14 in the organic matter that was the tree decreases due to the decay of C-14 to an isotope of nitrogen.
When we dig up the remnants of the tree today, we can measure the proportion of C-14 to C-12 and see how much it has been reduced. From this we can calculate backwards using the half life of C-14 (5730 years) to estimate how old the remains of the tree are.
Inconsistent as it can vary from time to time.
Answer:
D. Grass
Explanation:
Every living organism must contain one or more cells to be considered "living". Each cell, however, contains certain structures that perform specific roles called ORGANELLES. These organelles are of different types and hence, perform different tasks. For example, mitochondria is the power house of a cell i.e. site of energy production, and hence, is found in every eukaryotic cell.
On the other hand, chloroplast is an organelle designed to perform photosynthesis, which only occurs in plant cells. Since only plant cells can undergo photosynthesis, only plant cells can contain chloroplast. Hence, according to this question, GRASS as a type of plant is an organism that will contain both mitochondria and chloroplast in its cells.
I think it is <span>Symbiosis. But I dont know how to explain it</span>
