I think the answer is <span>C. mixture of ionic and molecular substances</span>
<span>In the particular
order from
top to bottom , the answers are;</span>
<span>Genetic drift</span>
Gene flow
<span>Natural Selection </span>
<span>Gene flow occurs
during migration where alleles from one population
are introduced to another population hence increasing the population diversity. </span>
Genetic<span> drift occurs when the allelic frequency of a population changes due factors such as calamities and emigration or natural selection.</span>
<span>Natural selection is the force of ‘survival for the
fittest’ that is applied differentially on the population
by nature. </span>
Cell divison is necessary to replace cells that are worn and aging. Cells do not have an indefinite life span. Fo example, the life span of a red blood cell is about 120 days.
Biomes
are very large ecological areas on the earth’s surface, with fauna and flora
(animals and plants) adapting to their environment. Biomes are often defined by
abiotic factors such as climate, relief, geology, soils and vegetation.
A biome<span> is NOT an ecosystem,
although in a way it can look like a massive ecosystem. If you take a closer
look, you will notice that plants or animals in any of the biomes have special
adaptations that make it possible for them to exist in that area. You may find
many units of ecosystems within one biome.
There are five major categories of biomes on earth. In these five, there are
many sub-biomes, under which are many more well defined ecosystems.
</span>
<span>The Desert Biom - Deserts
makeup about 20% of total land cover on earth and are characterized by
little (less than 50cm/yr) or no rainfall. Desert biomes come in four major kinds—
each of these having their unique features but have similarities in their
biotic and abiotic makeup. They are the Hot and Dry Deserts, Semi Arid
Deserts, Coastal Deserts and Cold Deserts, and within these are many
deserts located in many places of the world.</span>
The Aquatic Biome<span> - This
includes all water bodies on the earth’s surface. Aquatic biomes are grouped
into two, Freshwater Biomes (lakes and ponds, rivers and streams,
wetlands) and Marine Biomes (oceans,
coral reefs and estuaries). These biomes make up about 73% of the total
earth’s surface.</span>
The Forest Biome<span> - Forests
makeup about 30% of the total land cover on earth and are of incredible value
to life on earth. They are a
store of carbon and play a very important role in climate control. They have a watershed role and are a source of many raw materials that humans depend on. </span>
The
Grassland Biomes:<span> <span>There are
two main types of grassland biomes: the Savanna Grasslands and the Temperate
Grasslands. </span></span>
The Tundra
Biomes:<span> <span>There are
two major tundra biomes—The Artic Tundra and the Alpine Tundra. </span></span>
