Category: Entertainment & Media

The sequence of events, which take place during the completion of one heartbeat, is known as cardiac cycle. It involves repeated contraction and relaxation of the heart muscles. A contraction is termed systole and a relaxation is termed diastole. One complete heartbeat or cardiac cycle consists of one systole and one diastole. It lasts for about 0.8 seconds.The events that take place during the completion of one heartbeat are—the auricular systole, the ventricular systole and the joint diastole or complete cardiac diastole. Image Source: promocell.com ADVERTISEMENTS: Auricular systole: The two auricles act as a pump to force the venous blood into the ventricles.The ventricles are in diastole at this time. During auricular systole, the auricular muscles contract and the openings of venae cavae and pulmonary vein close. The tricuspid valve…

Mitosis occurs in four phases namely:i. Prophaseii. Metaphase ADVERTISEMENTS: iii. Anaphaseiv. TelophaseThe various phases of mitosis are nearly similar in both animal and plant cells. For better understanding, the mitosis in animal cells is described here and wherever variation occurs, the mitosis in plant cell is also described. (I) Prophase (Gk. Pro: Before, Phasis: Stage): Image Source: upload.wikimedia.org ADVERTISEMENTS: 1. This is the first and longest phase of mitosis.2. The chromatin material undergoes condensation (becomes short and thick) and changes into thread-like structures called chromosomes.3- Each chromosome has two thread-like structures called sister chromatids, which lie close to each other and remain attached at a point called centromere.4. As prophase advances, the chromosomes become shorter and condensed (thickened). ADVERTISEMENTS: 5. In animal cells, the centrosome initiates and regulate the cell…

The importance and the impact of the media, written or electronic cannot be marginalized in the world of today. In the modern world of quick communication and quick information, media plays a very crucial role. The original role of the media was and still is to give to the public all relevant information about occurrences in the country and the world. Now the written media includes a host of publications, dailies, fortnightly, weeklies, monthly all giving information about events with supplement of suggestions and comments by learned people. Today, the print media has acquired such proportions that, there is absolutely no avenue of knowledge or information that is left out. Multifarious avenues are being touched upon, whether it be local, national or international. All avenues of news, business, health, sports,…

Edmund Burke is acclaimed today as one of the originators of modern political conservatism. In particular, his defence of the virtues of tradition and prejudice in Reflections on the Revolution in France is considered exemplary as a statement of conservative principles.However, there is more to Burke’s philosophy than a simple celebration of the established social order. Not least, it is suffused with a thorough going scepticism about the character and capabilities of human beings, which led him to reject the Enlightenment view that reason can be readily employed to the betterment of mankind.In this sense, Burke’s ideas can be seen as a counterblast against the sort of Enlightenment thinking that was sweeping through Europe towards the end of the 18th century. Image Source: globomidia.com.br ADVERTISEMENTS: The French Revolution, at least…

The various events which happen during a brief contraction, or single twitch of a verteb­rate striated muscle fibre, are as follows: Image Source: i.ytimg.com1. As soon as muscle fibre or muscle is stimulated, immediately electrical events in the form of action potentials appear over the surface of muscle fibre. ADVERTISEMENTS: 2. These electrical events travel over the sarcolemma and down the numerous transverse tubules to the interior of the muscle.3. As a result calcium ions are released from the T-sarcotubular system or cisternae of the sarcoplasmic reticulum.4. Free liberated calcium ions bring about the sliding of the actin filaments in spaces between the myosin filaments, with the result contraction is effected in the muscle.This process requires energy which is derived from the breakdown of the ATP to ADP+ inorganic phosphate.…

We can observe most of the good and bad effects of competition within the school. The same thing happens in the world outside— only on a larger scale.In a school, we have examinations; inter-school, inter-house and inter-class sporting events; and debating, elocution, quiz, essay and other contests. They constitute the highlights of school life.Most often, students study best (and hardest) before an examination. Sometimes, during this period, they absorb in a single week a quantity of academic matter they had not been able to digest in the preceding few months! Importance attached to an examination acts as a spur to their mental powers and they discover new levels of ability in themselves. image source: petroleumkings.com/ ADVERTISEMENTS: If one were to strike out all the examinations, and therefore all competition, from…