A) A sound wave
The other 3 create mutations, are cells are hit by sound waves all the time and experience no mutations because of it
Answer:
A glance of earth taken from space will depict it blue. This blue colour is actually water, the major part of the earth is covered with water. We need water for almost everything, for example- drinking, bathing, cooking etc and therefore we should know about the properties of water. 65 % human body is composed of water. Water is essential for the survival of life on earth. Water is distributed unevenly on the earth’s surface. It forms a major solvent and dissolves almost every polar solute. So let us have a look at its properties.
Physical properties of water : Water is a colourless and tasteless liquid. The molecules of water have extensive hydrogen bonds resulting in unusual properties in the condensed form. This also leads to high melting and boiling points. As compared to other liquids, water has a higher specific heat, thermal conductivity, surface tension, dipole moment etc. These properties form the reason for its significance in the biosphere. Water is an excellent solvent and therefore it helps in the transportation of ions and molecules required for metabolism. It has a high latent heat of vaporization which helps in the regulation of body temperature
Chemical properties of water: Amphoteric nature:
Water can act as both acid and base, which means that it is amphoteric in nature.
Example:
Acidic Behaviour: H2O(l)+NH3(aq) ⇌ H3O+(aq)+NH+4(aq)
Basic Behavior: H2O(l)+H2S(aq) ⇌ H3O+(aq)+HS−(aq)
Redox reactions:
Electropositive elements reduce water to hydrogen molecule. Thus water is a great source of hydrogen. Let us see an example in this case:
2H2O(l)+2Na(s)→2NaOH(aq)+H2(g)
During the process of photosynthesis, water is oxidized to O2. As water can be oxidized and reduced, it is very useful in redox reactions.
Hydrolysis reaction
Water has a very strong hydrating tendency due to its dielectric constant. It dissolves many ionic compounds. Some covalent and ionic compounds can be hydrolyzed in water.
Explanation:
For centuries scientists thought the Universe always existed in a largely unchanged form, run like clockwork thanks to the laws of physics. But a Belgian priest and scientist called George Lemaitre put forward another idea. In 1927, he proposed that the Universe began as a large, pregnant and primeval atom, exploding and sending out the smaller atoms that we see today.
His idea went largely unnoticed. But in 1929 astronomer Edwin Hubble discovered that the Universe isn’t static but is in fact expanding. If so, some scientists reasoned that if you rewound the Universe's life then at some point it should have existed as a tiny, dense point. Critics dismissed this: the celebrated astronomer Fred Hoyle sarcastically called this concept the “Big Bang Theory"
