<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.
D since the next step in the scientific process would be to experiment
<h2>Answer:</h2>
<u>The objects that allow humans to access ground water are:</u>
- <u>A spring</u>
- <u>a well drilled into an aquifer
</u>
- <u>a well drilled below the water table</u>
<h2>Explanation:</h2>
Access to ground water can be gained if we dig a well or use any source that can provide us an access below the water table. A water table is the level below which the ground is saturated with water. So above the saturation level we cannot gain access to water therefore we must go below it. A spring springs from ground below water table and the same thing occurs for well or an aquifer if it is below the water table..
I am not sure how to answer
D. fossils will help you discover how old the rock is, fossils would not be included in the question if the answer does not relate to them
