Natural selection requires variation between individuals. Mutations and reproduction increase genetic variation in a population. Natural selection occurs when environmental pressures favor certain traits that are passed on to offspring.
OH- is common to bases.
Explanation:
The base is a is an ionic compounds which when placed in aqueous solution dissociates in to a cation and an anion OH-.
The presence of OH- in the solution shows that the solution is basic or alkaline.
From Bronsted and Lowry concept base is a molecule that accepts a proton for example in NaOH, Na is a proton donor and OH is the proton acceptor.
A base accepts hydrogen ion and the concentration of OH is always higher in base.
There is a presence of conjugate acid and conjugate base in the Bronsted and Lowry acid and base.
Conjugate acid is one which is formed when a base gained a proton.
Conjugate base is one which is formed when an acid looses a proton.
And from the Arrhenius base Theory, the base is one that dissociates in to water as OH-.
For example...
You have solution with [H+] = 0,01M
>>>> pH = -log[H+] = -log0,01 = 2
And you increase the [H+] by 10x ---> 0,01×10 = 0,1M
>>>> pH = -log0,1 = 1
○ pH decrease by 2x
○ pH is more acidic
<h3>Types of Osmosis</h3>
Osmosis is of two types:
Endosmosis– When a substance is placed in a hypotonic solution, the solvent molecules move inside the cell and the cell becomes turgid or undergoes deplasmolysis. This is known as endosmosis.
Exosmosis– When a substance is placed in a hypertonic solution, the solvent molecules move outside the cell and the cell becomes flaccid or undergoes plasmolysis. This is known as exosmosis.
There are several things that can help scientists evaluate which category something belongs to. The similarity in features is one of them. If two skulls looked alike, they were probably species of the same evolutionary category. For example say humans and monkeys rather than humans and dogs.
Similarly fossils have helped scientists categorise species. Study of the chromosomes (in cases with available chromosomes) can help scientists figure out a lot about the subjects and categorise them.
