Answer:
Friedrich Miescher discovered nucleic acids in blood cells.
Nuclein was discovered by Friedrich Miescher in 1869
Explanation
In the somewhat early 1880s Albert Kossel further purified the substance and discovered its highly acidic properties. Then he later discovered the nucleobases. In 1889 Richard Altman creates the term nucleic acid. Friedrich Miescher was the first scientist to ever isolate nucleic acid.
Answer:
Alfred Lothar Wegener was a German polar researcher, geophysicist and meteorologist. During his lifetime he was primarily known for his achievements in meteorology and as a pioneer of polar research.
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:
