General Science Questions (MCQs) for Competitive Examinations

Notes:
A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs. The pulmonary arteries are unique in that unlike most arteries which carry oxygenated blood to other parts of the body, the pulmonary arteries carry de-oxygenated blood to the lungs. After picking up oxygen, the oxygen rich blood is returned to the heart via the pulmonary veins.

Notes:
An analgesic or painkiller is any member of the group of drugs used to achieve analgesia, relief from pain. Analgesic drugs act in various ways on the peripheral and central nervous systems. They are distinct from anaesthetics, which temporarily affect, and in some instances completely eliminate, sensation.

Notes:
Vegetable and fruits should be a part of our diet because they stimulate peristalsis. Dietary fiber found in whole fresh fruits and vegetables and whole grains stimulates peristalsis, flushing out fats and waste. Gas-producing foods like broccoli and cabbage also stimulate peristalsis. Drinking plenty of fluids is important because it keeps stools soft and easy to pass.

Notes:
Insectivorous plants are : Aldrovanda, Archaeamphora, Brocchinia, Byblis, Catopsis, Dionaea, Drosera, Genlisea, Hel iamphora, Nepenthes, Palaeoaldrovanda, Philcoxia, Roridule, Sarracenia, Stylidium, Triphyophyllum, Utricularia etc. In India, it was introduced by Dr. M. Swaminathan under the leadership of Pt. Nehru.

Notes:
Anaemia is a condition that develops when blood lacks enough healthy red blood cells or haemoglobin. The three main types of Anaemia are due to blood loss, decreased red blood cell production, and increased red blood cell breakdown. Causes of decreased production include iron deficiency, a lack of vitamin B12, thalassemia, and a number of neoplasms of the bone marrow.

Notes:
According to the K+ ion theory the guard cells absorb K+ ions from the cells around them as they produce ATP (due to photosynthesis) and become hypertonic. This leads to absorption of water from nearby cells by endosmosis due to which the guard cells become turgid and the stomata opens. Decreasing light intensity and photosynthesis causes Stomatal closing.

Notes:
Casein-Lactose protein-sugar pair is present in milk. Normal bovine milk contains 30-35 grams of protein per litre of which about 80 percent is arranged in casein micelles. Casein is present in milk, but it’s not a milk sugar like lactose. Instead, casein is one of the proteins found in milk. Unlike lactose, which causes an intolerance, these proteins in milk are what’s responsible for a milk allergy, according to Food Allergy and Research Education.

Notes:
During glycolysis, glucose is broken down in ten steps to two molecules of pyruvate in cytoplasm (in the cellular matrix called cytosol). It then enters the mitochondria where it is oxidised through the tricarboxylic acid cycle to carbon dioxide and water.

Notes:
An insect is an organism having three pairs of jointed legs. Insects are small, land-dwelling arthropods. It has three distinct body sections : the head, thorax and abdomen. It has one pair of antennae (comprising the scapele, pedicel and flagellum), compound eyes and often one or two pairs of wings.

Notes:
The aorta is the largest artery of the human body. It is an artery that directly arises from the heart itself and descends through the thorax and into the abdomen. All the arteries of the body, save the pulmonary arteries, stem from the aorta or one of its main branches.