B.https://www.mansfieldct.org/Schools/MMS/staff/hand/genNaturalselection06.htm this is where I got my source.
Answer: Three
Reason/Explanation:
The cat, you and the dog are all different populations. Together, there are three populations.
-DustinBR
The xylem is the structure of the plant that is
responsible for transporting water from the ground up to the different parts of
the plant. It is composed water, inorganic ions, and a number of organic chemicals.
<span>
Xylem tissue is found throughout the plant
because not only does it transport water, but it also transports the nutrients
that the plant needs for different processes. Aside from being responsible for
the transportation of materials, the xylem is also used to replace water that
was lost during photosynthesis and transpiration. </span>
<span>One group is given a larger dosage than is typically prescribed.
A second group is given a smaller dosage than is typically prescribed
Then results of the groups are compared to each other.
The thing that is missing in this experimental design is a third group who are tested with the typical dosage.</span>
Alleles are the individual genes that give rise to certain characteristics in an organism.
When an allele is "fixed" to a population, this means that the characteristic will be constant & most likely will not change until the environment changes as well.
Like with arctic hare, the alleles that influence the color of their coats (white in the winter & brown in the spring/summer) will stay because any fur pattern other than the aforementioned characteristics with result in becoming someone else's food with the lack of camouflage.
Hope that helps!