A hydrogen bond forms from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom.
Answer:
B Physical separation of populations prevents interbreeding and mixing of gene pools.
Explanation:
Geographic isolation means two populations are unable to reproduce with one another. This means that over time, the variation in the gene pool will be different for one group compared to the other, and the species will genetically diverge from one another. resulting in speciation.
Answer:
The answer is C. An increase in competition for sunlight and space among plants
Trophic level: the feeding level of an organism in a food web or chain. Food web: a diagram showing a series of interconnected food chains and the flow of energy through an ecosystem. Food chain: a diagram showing the flow of energy from one trophic level to the next. E.g. Consumer or decomposed Consumer: an organism which feeds on other organisms to obtain its nutritional requirements (part of a food web/chain). Producer: an organism capable of trapping the suns energy and converting it to sugar in the process of photosynthesis. Therefore the term food web is the term used to include all of the above.
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B. To contrast between the high and low concentration of molecules.
for example a solution with a higher solute concentration than the inside of the cell is called hypertonic