The two ions are SODIUM AND CALCIUM IONS. Polarization refers to loss of polarization, that is, loss of the difference in charge between the inside and the outside of the plasma membrane of a muscle due to a change in permeability and migration of ion. When a heart muscle is depolarize, sodium ion and calcium ion channels open and they migrate into the cell from the outside.
Answer:
Vestigial organs
Explanation:
Vestigial organs/ structures are those parts of the body that have become redundant, weakened, or useless to the body as a result of prolonged inactiveness.
According to Charles Darwin's theory of evolution, he explains that parts of the body that are not used quite often do not develop any further, and as generations of offspring come and go, such parts become useless to the organism. This is the law of use/misuse of parts.
This is what happened to the whales. Over the years, the whales must have discovered that the legs were useless to them as they spent most of their time in the water. This led to the degeneration of such body part over thousands of generations, leaving them with just a faint trace of the hind limbs which were observed
The answer is Mutualism because they are both benefiting
Answer: Due to formation of carbonic acid, increased CO2 level will decrease the pH of earth waters.
Carbon dioxide could form carbonic acid when dissolved into water. Since it was acid, it will lower the pH of the water. The level of carbon dioxide in human body is regulated because of the same reason. Higher or lower pH will have a harmful effect on the organism that live in the water.