<span>
carbon ,hydrogen and oxygen </span>
Answer:
Stabilizing Variation.
Explanation:
This is the type of variation that occurs when genetic diversity decreases as the population of organism in a particular population based on a specific trait.
Organisms with varied or specific traits within the population are selected against by the selection pressure, with little chances of reproduction, while organisms in between, ( with least variation of this particular traits) which are within the narrow range, survive to reproduce.Thus, this gives rise to narrow population of these particular organisms,(stabilizing variation) which are therefore naturally selected.
Therefore, the variation of the organisms in this population is kept close to the centre of the same mean value.
Stromatolite fossils are the oldest known fossils<span>, that formed 3.5 billion years ago when the environments of Earth were too hostile to support life as we know it today. They </span><span>are layered mounds, columns, and sheet-like sedimentary rocks</span><span>
Stromatolite fossils indicate that </span>life must have arisen quite a bit earlier, perhaps 3.9 billion years ago.
Answer:
1) Use of aerosol sprays containing CFCS----Increase in greenhouse gases and causes Ozone depletion.
2) Use of extinguishers------ in the Combustion of fossil fuels.
3) Use of carbon tetrachloride as an
industrial solvent-----Agricultural activities
Explanation:
Aerosol sprays containing CFCS which is a harmful substance causes depletion of ozone layer which protects us from harmful radiation of the sun.
Carbon tetrachloride is used in agriculture activities such as a fumigant in the storage house for preventing the grains from pest attack.
Extinguishers are used for controlling the Combustion of fossil fuels.
