Questions

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.

Secondary succession means in an ecosystem renewal of itself after all or a portion has been destroyed.

After a forest fire, the whole forest had destroyed but after that again renewal of that forest is also an example of secondary succession.

Plants grow in size both in height and in grith. Enlargement  of cells already present cannot contribute much to the growth. Only addition of more and more cells could increase the size of the plant considerably.

Anaerobic glycolysis is the transformation of glucose to lactate when limited amounts of oxygen (O2) are available. 

Hence, Anaerobic glycolysis occurs without oxygen.