Answer:
Bone.
Explanation:
Calcium is one of the important element present in the body. Calcium plays an important role in the muscle contraction. The calcium ions also acts as a signalling molecule during cell signalling.
The calcium is present in our extracellular fluids, bones, and teeth. The major constituent of calcium is present in the bone. The bone consists of around 90% body;s calcium.
Thus, the correct answer is option (b).
Answer:
Yes.
Explanation:
If the graph line comes lowers from 1999 to 2013 so it means that steps taken by the EPA and the factories were effective in reducing air pollution. The steps taken by the EPA and the factories were effective in reducing air pollution occurs from two pollutants i. e nitrogen oxides (NOx) and sulfur dioxide (SO2) if they install chimneys which collect these gases and reduce pollution. if the factories uses coal having less concentration of sulphur so less air pollution occurs.
Answer: Natural selection is one of the forces of evolution and the enviroment where the species lives is the selection agent. For example, suppose a mosquitoes population in a environment free from insecticides, in this environment there's a high frequency of non-resistant mosquitoes because the environment is not exerting any pressure on the resistence trait. But when the environment changes and we use a insecticide upon the mosquitoes population, the populations changes because the non-resistant ones die but those resistant survive and beggin to reproduce more effectively. That's natural selection, differences in survival and reproduction between individuals with different phenotypes (traits) and this differences depend of environmental changes.
An example of plain language is federal government <span />
