FREE ESSAY ON METAMORPHOSIS

METAMORPHOSIS

Metamorphosis: In biology, striking change of form or structure in an individual after
hatching or birth. Hormones called molting and juvenile hormones, which are not species
specific, apparently regulate the changes. These physical changes as well as those
involving growth and differentiation are accompanied by alterations of the organism's
physiology, biochemistry, and behavior. From animal development.
Metamorphosis, the transformation of the larva into an adult, is a more or less
complicated process depending on the degree of difference between the two forms. The
transformation may be gradual, extend over a long period, and involve a number of
intermediate stages; alternatively, the transformation may be achieved in one step. In
the latter case, especially if the difference between the larva and adult is great, large
parts of the body of the larva, including all the specifically larval organs,
disintegrate (necrobiotic metamorphosis).
Critical mass: En nuclear physics, the minimum amount of a given fissile material
necessary to achieve a self-sustaining fission chain reaction under stated conditions.
Its size depends on several factors, including the kind of fissile material used, its
concentration and purity, and the composition and geometry of the surrounding reaction
system. History & Philosophy. The study either of the historical process and its
development or of the methods used by historians to understand their material. The term
history may be employed in two quite different senses: it may mean (1) the events and
actions that together make up the human past, or (2) the accounts given of that past and
the modes of investigation whereby they are arrived at or constructed.