Because cell is composed of organelle and several little material which haven't an ability to increase in size just in same manner as a rubber therefore cell divide for increase their number .
i hope this is helpful
Answer:
The above statement is false.
Explanation:
Protozoans are not the organisms that can convert nitrogen from the air into chemical compounds that plants can use.
Bacteria and archaea are organisms that can convert nitrogen from the air into chemical compounds that plants can use. Organisms which can convert nitrogen to forms that can be used by plants such as ammonia are known as diazotrophs. Examples of such kind of organisms include Rhizobia and azospirillium.
A. Cells mature and divide its very simple hope this helps
Reactions in which the concentration of Nucleophile or Base has no effect on the rate of reaction depends only on the concentration of substrate. Such reactions are called Unimolecular Substitution or Elimination Reactions. The Kinetics of such reaction is First order with respect to substrate.
Examples:
SN¹ Reactions: These are Unimolecular Substitution reactions. These are two step reactions in which the first step is the rate determining step. In RDS the substrate is ionized to generate a carbocation and is the slowest step. In second step the Nu attacks carbocation and is the fastest step.
E¹ Reactions: These are unimolecular Elimination reactions. These are also two step reaction. In first step carbocation is generated (RDS step) and in second step the base abstracts proton to yield alkene. These reactions only depend on the concentration of substrate.