Who discovered the process of fermentation?
Answer: B
Correct answer: Louis Pasteur
Louis Pasteur established in the 1850s that fermentation is the work of living microorganisms rather than a purely chemical change. The same investigations gave us pasteurisation and, in time, the germ theory of disease.
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What is the shape of an amoeba?
Answer: D
Correct answer: No definite shape
An amoeba has no fixed shape: it has no cell wall, and its cytoplasm flows into pseudopodia that it uses to move and to engulf food. Its outline is therefore always changing.
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Rhizobium bacteria are present in the _____ of leguminous plants.
Answer: A
Correct answer: Roots
Rhizobium lives in nodules on the roots of legumes - peas, beans, gram, groundnut. The nodule is a structure the plant builds around the bacteria, and its pink colour comes from leghaemoglobin, which keeps oxygen away from the nitrogenase that oxygen would destroy.
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Which of these is a saprotroph?
Answer: C
Correct answer: Fungi
Fungi are saprotrophs: they secrete enzymes onto dead organic matter and absorb the digested products. The pitcher plant is an insectivorous autotroph, and Cuscuta is a parasite that feeds on a living host.
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Prokaryotes do not have a
Answer: C
Correct answer: Nuclear membrane
A prokaryote has no nuclear membrane - its chromosome lies free in the cytoplasm as a nucleoid. It does have cytoplasm, ribosomes (of the 70S kind) and a chromosome; what it lacks is that membrane and the other membrane-bound organelles.
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Which of the following does not have the capacity to reproduce outside the host cell?
Answer: D
Correct answer: Virus
A virus has no ribosomes and no metabolism, so it can only replicate inside a living host cell, using the host’s machinery. Bacteria, fungi and algae are complete cells and multiply on their own.
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What type of microorganism is yeast which is used in many food preparations?
Answer: B
Correct answer: Fungi
Yeast is a single-celled fungus. It ferments sugars to alcohol and carbon dioxide, which is what makes it useful for both baking and brewing - the same process, with a different product wanted in each case.
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Penicillium, from which an antibiotic is obtained, is a type of -
Answer: D
Correct answer: Fungus
Penicillium is a mould, that is a filamentous fungus. Fleming noticed in 1928 that a colony of it contaminating a plate had killed the bacteria around it, and penicillin was the result.
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The sole members of the kingdom Monera are
Answer: D
Correct answer: Bacteria
Monera is the kingdom of prokaryotes - the bacteria, including the cyanobacteria. It is defined by the absence of a nucleus and of membrane-bound organelles. Mushrooms are fungi, algae are protists or plants, and viruses are not placed in any kingdom, being non-cellular.
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Litmus, used as an indicator for acids and bases, is extracted from
Answer: A
Correct answer: Lichens
Litmus is extracted from lichens, chiefly Roccella species. It turns red in acid and blue in alkali, and was one of the earliest chemical indicators - used long before anyone understood why it worked.
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