General Science Questions (MCQs) for Competitive Examinations

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The lateral line is a system of sense organs found in aquatic vertebrates, chiefly fish. It is used to detect movement and vibration in the surrounding water. Sea Horses do not have such organ.

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Certain plants which possess the C4 dicarboxylic acid pathway of CO2 fixations show a structural dimorphism of chloroplast structure. Sugarcane is a common example of C4 plant that has dimorphic chloroplast. The mesophyll cells possess chloroplasts with well developed grana whereas the bundle sheath chloroplasts lack the organization of grana (Agranal chloroplasts). The malic acid is transported to the bundle sheath chloroplast (Transportations). Here it is converted to pyruvic acid and CO 2 by NADP+ malic enzyme (Decarboxylation). The pyruvic acid is then transported to mesophyll chloroplasts (Transportation).

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Hepatitis is an inflammation of the liver. Viruses cause most cases of hepatitis. There are 5 main hepatitis viruses, referred to as types A, B, C, D and E. The type of hepatitis is named for the virus that causes it; for example, hepatitis A, hepatitis B or hepatitis C. Drug or alcohol use can also cause hepatitis.

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Damping off is a horticultural disease or condition, caused by a number of different pathogens that kill or weaken seeds or seedlings before or after they germinate. Pythium, a genus of parasitic oomycete, are most often responsible for damping-off. Along with Rhizoctonia solani, attacks by Pythium are most associated with producing roughly circular patches of dead seedlings.

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Hydrogen peroxide (H2O2) is a water molecule with an extra oxygen atom hence, also called oxygenated water. It is very unstable and breaks down readily into water and a single oxygen molecule. So in nutshell, when Hydrogen peroxide readily loses active oxygen, Water is formed.
2H2O2 —> 2H2O + O2

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The National Institute of Mental Health and Nuro- Sciences is a premier medical institution located in Bengaluru, India. NIMHANS is the apex centre for mental health and neuroscience education in the country, the institute operates autonomously under the Ministry of Health and Family Welfare.

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The main source of atmospheric free oxygen is photosynthesis, which produces sugars and free oxygen from carbon dioxide and water. The organisms that carry out photosynthesis include the plant life of the land areas as well as the phytoplankton of the oceans.
6CO2 + 6H2O + energy —> C6H12O6 + 6O2

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True berries, such as blueberries and cranberries have seeds inside. The strawberry, however has its dry, yellow “seeds” on the outside (each of which is actually considered a separate fruit). The “seeds” seen on the outside of a strawberry are actually the plant’s ovaries and are called “achnes.”

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Beriberi is a disease caused by a vitamin B1 (thiamine) deficiency. There are two types of the disease: wet beriberi and dry beriberi. Wet beriberi affects the heart and circulatory system. In extreme cases, wet beriberi can cause heart failure. Dry beriberi damages the nerves and can lead to a loss of muscle strength and eventually, muscle paralysis.

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All the three names, indica, tuberosum and leo, represent the specific epithets, while the first words Mangifera, Solanum and Panthera are genera and represents another higher level of taxon or category. Each genus may have one or more than one specific epithets representing different organisms, but having morphological similarities.