They are mostly habittated to watter because they requres oxygen more from water or there organ setup to do it works properly under water.
A and B can react to form C and D or, in the reverse reaction, C and D can react to form A and B. This is distinct from reversible process in thermodynamics.
Weak acids and bases undertake reversible reactions. For example, carbonic acid: H2CO3 (l) + H2O(l) ⇌ HCO−3 (aq) + H3O+(aq).
The concentrations of reactants and products in an equilibrium mixture are determined by the analytical concentrations of the reagents (A and B or C and D) and the equilibrium constant, K. The magnitude of the equilibrium constant depends on the Gibbs free energy change for the reaction.[2] So, when the free energy change is large (more than about 30 kJ mol−1), then the equilibrium constant is large (log K > 3) and the concentrations of the reactants at equilibrium are very small. Such a reaction is sometimes considered to be an irreversible reaction, although in reality small amounts of the reactants are still expected to be present in the reacting system. A truly irreversible chemical reaction is usually achieved when one of the products exits the reacting system, for example, as does carbon dioxide (volatile) in the reaction
This is a neutral atom of chlorine.
There are several ways selection can affect population variation:
stabilizing selection
directional selection
diversifying selection
frequency-dependent selection
sexual selection
As natural selection influences the allele frequencies in a population, individuals can either become more or less genetically similar and the phenotypes displayed can become more similar or more disparate. In the end, natural selection cannot produce perfect organisms from scratch, it can only generate populations that are better adapted to survive and successfully reproduce in their environments through the aforementioned selections.
Hope it helped, much love
The jokester, hehe
From several more prokaryotic cells.