<u>Answer</u>:
1. The purpose of the uninoculated control tubes used in the oxidation fermentation test is to serve as basis of the medium for the color comparison and that it is sterile.
2. It is necessary to use two controls in order to illustrate the no color change (green color) under both aerobic and anaerobic conditions.
3. The purpose of the experiment is to determine if the organisms utilize the carbohydrate and thus is fermentative. This will result in a color change from green to yellow.
Thus, the medium in one tube is sealed with a layer of paraffin to prevent diffusion of oxygen. This tube will show that the medium is unaffected by the lack of oxygen.
The second tube will allow the diffusion of oxygen. This tube will show that the medium does not change color naturally in the presence of oxygen. Thus, the color changes will be caused only by the fermentation process of the organisms.
DDT increases as it moves up a food chain.
<h3>Explain how?</h3>
DDT increases or biomagnifies if we look at a food chain. DDT is fat-soluble, which means animals store it in fatty tissues. It also takes a relatively long amount of time to break down.
Thus, if a predator consumes multiple organisms and each organism has a small amount of DDT, the amount of DDT in the predator is going to be the result of all of those small amounts combined.
To learn more about DDT click here:
brainly.com/question/27536734
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Answer:
How to figure out how soil
Explanation:
edit: sorry if wrong :[
edit: it is showing how the under the soil there is a substance that is holding it up
In negative control, a gene is switched off when a regulatory protein binds to DNA and shuts down transcription.
One might be it's not alive
