For giving you understanding ; we need Free O2 but Oxygen is also available in H20 right why dont we use it !!
As the early atmosphere was reducing as there was no free oxygen but it was later produced by chemoautotrophic bacteria !! Living thing release O2 in atmosphere thus making it oxidising in nature and then life evolves !!
When people used stone tools,
The in-between period of time when the first man appeared and when man developed a writing system. Or the period of time before man became literate.
Answer:
A. amount of food available
Explanation:
An experiment consists of two types of variables, independent and dependent. Value of independent variable is decided by the person doing the experiment and is independent of experimental conditions. Value of dependent variable is dependent on the independent variable. It can not be altered by the person doing experiment.
Here, it is given that mice receive variable amount of food each day and their lifespan is recorded. Since the amount of food is decided already it is the independent variable. The lifespan is expected to depend on the amount of food hence it is the dependent variable.
The answer is false (sorry I'm late.)
It is important to study the cell in order to learn about DNA is that there many different processes that help to keep a cell running. In order to know DNA, you need to familiarize yourself with mRNA, tRNA, and rRNA to learn the process of transcription and translation- two very important processes in DNA.