Exams

When moon's orbit is closest to earth is called as Perigee.

The distance between the Moon and Earth varies throughout the month and the year since the moon's orbit around the earth is elliptical. The distance is about 382,900 kilometers from the Moon's center to the center of Earth.

Hence, the point on the Moon's orbit closest to Earth is called the perigee.

Cell membranes are made up of phospholipids which prevents them from dissolving in water.

Any factor limiting the size of a population whose effect is not dependent on the number of individuals in the population, then such factor is called Density Independent Factor. It is things that the organisms have no control over.

Here in the given options, food shortage and disease are factors that are dependent on the number of population but Floods have no dependency.

Some examples of density independent factors are :: Earth quake, fires, volcanic eruptions, floods, and  all natural calamities.