Answer:
A serial dilution and the following plating experiment is done in order to determine the actual amount of bacteria/microbes in a specific volume of soil sample. As a standard test, a set volume of the lower dilution is obtained and positioned on a median plate and permitted to increase for the needed amount of time. The amount of colonies is evaluated and thus the overall Colony Forming Units (CFU) is determined by unit volume of the sample plated and therefore the volume of soil sample employed.
Therefore,
The calculation is done using:
CFU/ml = Number of colonies appeared × dilution factor / volume plated
Given,
Number of colonies appeared = 97
dilution factor = 10^(-6)
volume plated = 1/10 = 0.1
This will help us calculate it as:
CFU/ml = 97 * 10^(-6) / 0.1
= 97 * 10^(-7) CFU/ml
This CFU/ml helps determine the amount of bacterial colonies per unit volume of sample plated.
Given,
The original sample as 1g or 1000 mg of soil in its total volume.
Therefore,
The number of bacteria can be calculated using:
Amount of bacteria in original sample
= 97 * 10^(-7) CFU/ml × 1/ 1000 mg
= 9.7 * 10^(-3) CFU/mg
Scientists can access the risks of trans fats by conducting an appropriate experiment which will show the effects of the fats on the human system.
This can be done by feeding known quantity of trans fats to rats over a specific period of time. During the period, the change in the rat weights will be measured on the daily basis and every other changes that is noted in the rats will be noted down. A control group of rats will be included in the experiment; these rats will be given normal rat feeds and not trans fats.
When the period of feeding is completed, the rats will be killed, all the organs in the rats such as liver, blood, brains, kidney, etc will be harvested and these organs will then be biochemically analysed in order to compare the changes in them with that of a normal rats.
Rats are usually used in biochemical research because their systems and that of human is comparable. Any negative effect of trans fats that is noted in the rats will also hold true for human beings.
Answer:
Consumer
Explanation:
Producer An organism that can make its own food
Consumer An organism that obtains energy by feeding on other organisms
herbivores consumers that eat only plants
carnivores consumers that eat only animals
