Answer;
-They are polar
Explanation;
-A phospholipid is a lipid that contains a phosphate group and is a major component of cell membranes. A phospholipid consists of a hydrophilic (water-loving) head and hydrophobic (water-fearing) tail. Hydrophilic / hydrophobic layers restrict the passage of many substances.
-When phospholipids are mixed with water, they spontaneously rearrange themselves to form the lowest free-energy configuration. This means that the hydrophobic regions find ways to remove themselves from water, while the hydrophilic regions interact with water.
Answer:
Mechanical Isolation
A snail with a flat disc-like shell
will not be able to mate with a
snail having a conical shell.
The reproductive organs of
male bush babies do not
match with the reproductive
organs of females of other
bush baby species
Behavioral Isolation
The mating call of a cricket is not
recognized by a cricket of other
species.
The signals sent by a male firefly
are not recognized by the female
firefly of other species.
Explanation:
Mechanical isolation occurs in the scenario where two organisms are willing to mate but cannot do so due to the physical challenges. As in the case of snail a flat disk and a conical disk snail are willing to mate but physical barriers restrict them in doing so.
The same case is with the male and female bush babies where the difference in reproductive organs does not allow them to mate.
Behavioral isolation represents a scenario where two organisms are unaware of mating rituals, season, pattern or signals of each other and hence cannot mate.
For example – male and female cricket do not recognize the mating call of each other. Likewise male and female firefly is also not able to understand each other’s mating signal.
It could be the cell membrane which is a barrier, thinner than the cell wall, that protects the cell and controls transport from within and outside the cell.
