summary with character sketch

Mendel postulated that there are certain physical entities called the factors that are responsible for the transmission of characters; these factors are now called gene..

Animals may reproduce by asexual and sexual modes. The reproductive system of sexually reproducing animals consists of primary sex organs which produce the gametes, the secondary sex organs which participate in reproduction but do not form gametes and accessory sex characters which ..

Heredity may be defined as the transmission of characteristics through generations Variation may be defined as differences among individuals of a species Both heredity and variation play important roles in evolution of organisms The study of the mechanism of transmission of characteristi..

+ in the body and elimination of K + from the body. Glucocorticoids such as cortisol regulate the metabolism of carbohydrates, proteins and fats. Sex corticoids develop external male sex characters. Failure of corticosteroid secretion causes Addisons disease. Over secretion causes Cush..

Smallest unit of ecological hierarchy is the organism, while smallest and basic unit of taxonomic hierarchy is species. A group of individuals, having similar structural and functional characters, capable of potential interbreeding is termed as species. In nature all apecies exhibit coope..

Biologists estimate that there are about 30 million species of living organisms inhabiting this biosphere and only a million and half of it have been discovered and described so far. The species of plants and animals identified so far exhibit a great deal of variation in their form, structure ..

. Fired and spent, her voice lost its beauty and the creatures stopped coming to hear her sing. Morose and depressed, she refused to sing, but the frog goaded her to practice. Scared and unhappy, the nightingale tried, burst a vein, and died. The frog, unsympathetic, dismissed her off - calling her..

Organic evolution refers to the slow and gradual process by which living organisms have changed from the simplest unicellular form to the most complex multi-cellular forms that are existing today. Organic evolution primarily involves modifications in the existing organisms and the inheritance ..

>Group number is number of electrons in the valence shell. Elements having the same valence number, are grouped together. The number of shells present in the atom gives period number. Metallic character decreases along a period and increases down a group. Valency of an element with respec..

. Chromatin network is formed by the long and coiled DNA molecule and histone proteins. The chromatin network condenses into chromosomes at the time of cell division. Nucleolus is composed of ribosomes and RNA. Nucleus is the controlling centre of the cell. It is also involved in the transmission o..