Answer: variation, reproduction, and heritability.
Explanation: Genetic variation is an important force in evolution as it allows natural selection to increase or decrease frequency of alleles already in the population. Genetic variation is advantageous to a population because it enables some individuals to adapt to the environment while maintaining the survival of the population.
All species must reproduce to survive. Organisms cannot live forever, so they must reproduce to allow their species to continue to live on. Reproduction is nature's way of allowing a species to survive.
Higher heritability means the trait evolves faster; fewer generations are required for the trait to increase to the same degree as a trait with lower heritability. For this reason, genetic correlation and heritability show how a trait might change from one generation to the next and into the future.
For the environmental risk, it is much better to prevent pollution than to deal with it after it has already been made. When you deal with the pollution, it is hard to say that you can eliminate completely. So, prevention is the first strategy.

<h2>Fixation</h2>
Nitrogen in its gaseous form (N2) can’t be used by most living things. It has to be converted or ‘fixed’ to a more usable form through a process called fixation. There are three ways nitrogen can be fixed to be useful for living things:
<h3>Biologically: </h3>
Nitrogen gas (N2) diffuses into the soil from the atmosphere, and species of bacteria convert this nitrogen to ammonium ions (NH4+), which can be used by plants. Legumes (such as clover and lupins) are often grown by farmers because they have nodules on their roots that contain nitrogen-fixing bacteria.
<h3>Through lightning: </h3>
Lightning converts atmospheric nitrogen into ammonia and nitrate (NO3) that enter soil with rainfall.

Answer:
The alleles for MADS-box genes get expressed at different levels. They form the “L” complex and the “SP” complex. These are a group of proteins that determine the shape of the petals. The more they L complex is expressed, the high the probability that the petals of the flower will form the ‘lip’ and the high the SP complex is expressed then the high the likelihood of dominant petals.
Explanation:
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