Fragmentation, leaching and catabolism are some of the important steps decomposition. Study the following statements ((i), (ii) and (iii)) regarding these am select the correct option.
(i) Detritivores (e.g., earthworm) break down detritus into smaller particles.
(ii) Water soluble inorganic nutrients go down into soil horizon and get precipitatel as unavailable salts.
(iii) Decomposers (e.g., bacteria and fungi) excrete digestive enzymes and degrade detritus into simpler inorganic substances.
3' AAA TGC GCG ATA 5' is the sequence of nucleotides on a gene. After transcription the mRNA formed against it and the sequence of bases in the corresponding bindim anticodons will be
Fruit shape in shephered's purse (Capsella bursa) is of two types-triangular and top-shaped. Triangular fruit shape (T) is dominant over top-shape (t). Following table summarises the results of several crosses:
Two insect species were used in a laboratory experiment. For one treatment, both species were grown by themselves (in separate chambers) on a suitable food source. For the second treatment, the two species were grown together (in the same chamber) on the same type and amount of food as in the first treatment. The two species were grown together (in the same chamber on the same type and amount of food as in the first treatment. The given figure shows the results (the number of individuals of each species in the two treatments) at the end of the experiment. Based on these results the two species should Grow alone be classified as
The given graph represents the effect of sewage a discharge on some important characteristics Peak Y of river. Select the correct option with respect to the peaks X and Y.
A)
Peak X-Sharp increase in BOD, disappearance of clean water organisms, Distance downstream Peak Y - Increase in dissolved oxygen, Sewage reappearance of clean water organisms added
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B)
Peak X - Increase in dissolved oxygen, reappearance of clean water organisms, Peak Y - Sharp decline in dissolved oxygen, disappearance of clean water Organisms
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C)
Peak X - Sharp increase in BOD, appearance of clean water organisms, Peak Y - Increase in dissolved oxygen, disappearance of clean water organisms
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D)
Peak X - Increased number of anaerobic bacteria, disappearance of clean water organisms, Peak Y - Sharp decline in dissolved reappearance of clean water organisms
Given is a diagram of food web of a terrestrial ecosystem. The arrows represent energy flow and the letters represent different species. In which species would a toxic pollutant that accumulates in animals probably reach the highest concentration?
Which of the following statements regarding birth control are not true?
Saheli, a new oral contraceptive for females was developed by scientists at Central Drug Research Institute (CDRI), Delhi.
Lactational amenorrhoea method is based on the fact that ovulation and therefore the menstrual cycle do not occur during the period of intense lactation following parturition. Therefore, as long as the mother breast feeds the child fully, chances of conception are almost nil.
Diaphragms, cervical caps and vaults are intrauterine devices.
Vasectomy and tubectomy are surgical removal of ovaries and testes respectively. Both these methods are reversible.
A hospital technician, while doing some routine culturing of micro-organisms in a lab, noticed a bacterial colony growing on a culture medium containing three different antibiotics. He identified the bacterium as one that did not cause a human disease, but he still reported his observation to the hospital administration. Why is he so worried?
A)
He had no way of killing this bacterium now that it was resistant to antibiotics.
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B)
Resistance to antibiotics could be transferred to disease-causing bacteria by transduction or conjugation.
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C)
The bacterium might feed on the antibiotics and therefore be able to grow in people taking these antibiotics.
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D)
If people accidentally ingested the bacteria with their food, they would become resistant to the antibiotic.
Given below are four statements (a-d) each with one or two blanks. Select the option which correctly fills up the blanks in the two statements. Plague is caused by (i), a deadly bacterium, (ii), the most common form of plague is characterized by high fever, weakness and acute painful swellings of the lymph nodes. Filariasis is characterised by swelling of the (i) and of other parts of the body. The disease, therefore, is commonly known as (ii) due to its resemblance to leg of an elephant. (i) is the resistance to infection which an individual possesses by virtue of his/her genetic and constitutional make up. (i) literally means "protection against self"; (ii) is an example of it.
A)
-(i) Neck, (ii) Ascariasis -(i)Autoimmunity,(ii)Diabetes mellitus
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B)
-(i)Bordetella pertussis, (ii) Pulmonary plague -(i) Passive immunity
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C)
-(i) Yersinia pestis, (ii) Bubonic plague -(i)Autoimmunity,(ii)Rheumatoid arthritis
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D)
-(i) Leg, (ii) Elephantiasis -(i) Acquired immunity