Biology MCQs

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Lassa and Ebola are emergent viruses in W. Africa originated by Fruit bats. Ebola hemorrhagic fever is caused by Ebola virus infection.

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Culex mosquito vectors are responsible for transmitting the parasite causing filariasis.

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The technique of genetic engineering crosses the limits of conventional hybridization processes.

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Transgenic plants have desirable traits like herbicide resistance. The inherited ability of an individual plant to survive the application of a herbicide that would kill a general population of the same species is called herbicide resistance.

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Saprophytes are the organisms which depend for food on dead and decaying material. They secrete digestive substances into the surrounding environment and break down the organic matter into simpler substances. The nutrients thus produced are absorbed directly through the cell membranes of the organisms.

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The word angiosperm means seed. The seeds develop inside an organ which is modified to become a fruit. These are also called flowering plants. Plant embryos in seeds have structures called cotyledons. Cotyledons are called ‘seed leaves’ because in many instances they emerge and become green when the seed germinates.

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While fertilization is necessary for organisms that reproduce sexually, individuals that reproduce asexually?do so without the need for fertilization. These organisms produce genetically identical copies of themselves through?binary fission, budding, fragmentation, parthenogenesis, or other forms of asexual reproduction.

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Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. It is a complex carbohydrate, (C6H10O5)n, that is composed of glucose units.

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Leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called “blasts”. Damage to the bone marrow, by way of displacing the normal bone marrow cells with higher numbers of immature white blood cells, results in a lack of blood platelets, which are important in the blood clotting process. This means people with leukaemia may easily become bruised, bleed excessively, or develop pinprick bleeds (petechiae). White blood cells, which are involved in fighting pathogens, may be suppressed or dysfunctional. This could cause the patient’s immune system to be unable to fight off a simple infection or to start attacking other normal body cells.

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Sea hares are molluscs. They belong to Phylum Mollusca and Class Gastropoda like snails. Like many other sea slugs (Subclass Opistobranchia), sea hares lack external shells as adults. Sea hares belong to Order Anaspidea.