Answer: A) The 'lub' sound is caused as the atrioventricular valves close.
Explanation:
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Answer:
a) and b) All the 12 plates taken by the food controller for the analysis are test plates in light of the fact that the food inspector is trying distinctive spinach from 10 unique bundles and do try different things with every one of the 12 plates.
C) and D).only #11 plate is a negative control since he utilized the spinach which isn't cleaned. so microorganisms can develop on that pate because they have the positive condition to develop themselves.
e) and f). all #1 - #10 and #12 plates are positive control plates since he swipes all the plates and spinach that can be the reason for the development of microbes so there is an excess of fewer opportunities to the defiling of spinach and he is playing it safe.
Endospore staining is used to stain the spore which reside inside the microorganisms, and unlike the exospores, are not present outside the microbial cells. The endospore stain penetrates the microbial cells, and then stain the endospore.
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