pre ap biology help

Pre-molars are bigger than incisors and canines and are flattened on top. There are four pre-molars each on upper and lower jaws, two on either side. The first pre-molar on the upper jaw has two root canals. All others have one. The surface has small humps which facil..

There have been several explanations on the possible mechanism of inheritance of traits from the parent to the offspring, put forth from time to time by different biologists. All these early theories presume that the characteristics of the two parents somehow mix during inheritance. Hence the..

There have been several explanations on the possible mechanism of inheritance of traits from the parent to the offspring, put forth from time to time by different biologists. All these early theories presume that the characteristics of the two parents somehow mix during inheritance. Hence these ide..

Is also referred as 'Origin of species'. All new species develop from pre existing ones. The formation of one or more new species from the pre existing species is called 'Speciation..

According to the modified cell principle, new cells arise only from pre-existing cells. Cells transfer their genetic information only by way of cell divisio..

Introduction - One of the main ideas in the modified cell principle is that new cells arise from pre-existing cells (Omnis cellula e cellula). Every new cell formed must inherit not only the nucleus which contains the genetic information, but also should inherit the cell organelles that a..

CHRONOLOGY OF SIGNIFICANT EVENTS IN CELL BIOLOGY YEAR EVENT 1500 Jansen designed the first conpound microscope by containing two lenses. 1665 Robert Hooke examined a thin section of bottle cork and described the basic unit as 'cell'. 1665-70 Antony Vo..

An organism, may be small unicellular or multicellular. Organisms have a fixed life span and organised life cycle comprising of birth, growth, maturity, old age and death. They are always derived from pre-existing ones through the mechanism of reproduction. The offspring resembles the pa..

Evolution may be defined as a gradual development of more complex species from pre-existing simpler forms. It is an extremely slow process and has occurred over millions of years. Evolution that has occurred is clear because of the evidences of fossils, etc. However, the mechanism of evol..

One of the main ideas in the modified cell principle is that new cells arise from pre-existing cells (Omnis cellula e cellula). Every new cell formed must inherit not only the nucleus which contains the genetic information, but also should inherit the cell organelles that are requir..