Science Tech

 Types of respiration External Respiration One method for obtaining oxygen from the environment is through external respiration or breathing. In animal organisms, the process of external respiration is performed in a number of different ways. Animals that lack specialized organs for respiration rely on diffusion across external tissue surfaces to obtain oxygen. Others … Read more

 Types of Asexual Reproduction Spores Some protozoans and many bacteria, plants and fungi reproduce via spores. Spores are structures naturally grown as part of an organism’s life cycle and designed for separation from the organism and dispersal via a medium such as air or water. When conditions are correct, the organism will release … Read more

   QUICK REVISION ( ARTICLE:3, SCIENCE): TYPE OF NUCLEAR REACTORS   COMPONENTS OF NUCLEAR REACTOR:   Fuel: Usually pellets of uranium oxide (UO2) arranged in tubes to form fuel rods. The rods are arranged into fuel assemblies in the reactor core   • Moderator: This is material which slows down the neutrons released … Read more

 Transport of water and minerals in plants and animals   Transport of water in plants The survival of plants is dependent on a number of factors which include water, minerals, gases, and nutrients they receive. The movement of gas, water, and nutrients in plants are carried out in components. They take in carbon … Read more

 Transgenic animals Transgenic animals are animals that have been cloned. The medical and biotechnological uses of animal cloning are almost innumerable, as many diseases have been eradicated thanks to the production of these transgenic animals. Transgenic animals development Since the discovery of the molecular structure of DNA by Watson and Crick in 1953, … Read more

 Transgenic Plants Transgenic plants are plants that have been genetically modified by inserting genes directly into a single plant cell. Transgenic crop plants modified for improved flavor, pest resistance, or some other useful property are being used increasingly.   Transgenic plants are unique in that they develop from only one plant cell. In … Read more

 Total internal reflection Total internal reflection, in physics, complete reflection of a ray of light within a medium such as water or glass from the surrounding surfaces back into the medium. The phenomenon occurs if the angle of incidence is greater than a certain limiting angle, called the critical angle. In general, total … Read more

 Topological & Non-Topological Conservation    Conservation – shape and structure of networks of interacting organisms in ecological systems In-Situ Conservation    Protect whole ecosystem at all levels to protect threatened species (save entire forest to save tiger)  Hot Spots – High endemism & high species richness (in India – Western Ghats (Agasthyamalai hills, … Read more

 Tissues Tissue, in physiology, a level of organization in multicellular organisms; it consists of a group of structurally and functionally similar cells and their intercellular material. Tissues are absent from unicellular organisms. Even among the simplest multicellular species, such as sponges, tissues are lacking or are poorly differentiated. But multicellular animals and plants … Read more

 Tissue culture Tissue culture, a method of biological research in which fragments of tissue from an animal or plant are transferred to an artificial environment in which they can continue to survive and function. The cultured tissue may consist of a single cell, a population of cells, or a whole or part of … Read more