In humans each lung is encased in a thin membraneous sac called the Pleura, and each is connected with the trachea (windpipe) by its main bronchus (large air passageway) and with the heart by the pulmonary arteries. Each Pleura can be divided into two parts: Visceral pleura-envelops the lung. Parietal pleura- covers the internal surface … Read more
Octahedral Complexes Octahedral complexes have six ligands symmetrically arranged around a central atom, defining the vertices of an octahedron. Octahedral molecular geometry describes the shape of compounds wherein six atoms or groups of atoms or ligands are symmetrically arranged around a central atom. The octahedron has eight faces, hence the prefix octa-. An example of … Read more
What Is Endosmosis? When a cell is placed in a hypotonic solution, the water move inside the cell causing it to swell or bulge. This movement of water inside a cell is known as endosmosis. This happens because the solute concentration of the surrounding solution is less than that inside the cytoplasm of the cell. … Read more
Thick and thin blood smears are commonly used to determine whether a person has malaria or not. If one test is negative and no parasites are found, there will be repeated blood smears every 8 hours for a couple of days to confirm that there is no malaria infection. Blood smears are most often taken … Read more
Velocity is a rate of change of the position of an object within a certain time range. There are two different types of velocity: angular velocity and linear velocity. Linear velocity is the rate of change of the position of an object that is traveling along a straight path. Any object that moves has a linear velocity. On … Read more
Nephridium is unit of the excretory system in many primitive invertebrates and also in the amphioxus; it expels wastes from the body cavity to the (usually aquatic) exterior. The evolution of nephridia encouraged tissue specialization by eliminating the need for all cells of an organism to be in contact with seawater for diffusion of metabolic wastes. Nephridia … Read more
What Is Starch? Starch is the most important source of carbohydrates in the human diet and accounts for more than 50% of our carbohydrate intake. It occurs in plants in the form of granules, and these are particularly abundant in seeds (especially the cereal grains) and tubers, where they serve as a storage form of … Read more
What is a Pound? A pound is a unit of measuring mass that belongs to the imperial system of units. Pound is commonly used in the United States of America and the United Kingdom as a unit for measurement of mass. Pound can express both force and mass; and is generally abbreviated as ‘lb’ due … Read more
What Is Deliquescence? Deliquescence, the process by which a substance absorbs moisture from the atmosphere until it dissolves in the absorbed water and forms a solution. Deliquescence occurs when the vapour pressure of the solution that is formed is less than the partial pressure of water vapour in the air. Unlike hygroscopy, however, deliquescence involves absorbing sufficient … Read more
What Is Polyp? Polyp is one of two principal body forms occurring in members of the animal phylum Cnidaria. The polyp may be solitary, as in the sea anemone, or colonial, as in coral, and is sessile (attached to a surface). The upper, or free, end of the body, which is hollow and cylindrical, typically has a mouth surrounded by extensible tentacles that bear … Read more