The term for blue skin caused by lack of oxygen is cyanosis. One is said to be cyanotic when presenting with this discoloration.
Answer:
The correct option is 3
Explanation:
An experimental investigation would require an hypothesis, aim, methodology, results, discussion and conclusion.
The third option can be easily answered using the "requirements" above.
The hypothesis (null hypothesis) would be different types of grass do not affect how far a ball rolls
The aim would be to determine the effect of different types of grass on the movement of a ball
The methodology would involve identifying several playing grounds with different grasses and then rolling the ball with a constant force on the different grasses and then determining the eventual speed and distance traveled by the ball on those grasses which would serve as the results. Inferences can then be made from this results and then conclusions drawn subsequently.
Answer:
An experiment where an antibiotic is tested against bacteria. The antibiotic can vary in its concentration for example, different amounts are applied to a sample of bacteria to see if it is affected by the action of the antibiotic and if so, in what concentration. So, the independent variable is the concentration of antibiotic while the dependent variable is the survival (or not) of the bacteria.
Explanation:
An independent variable is a variable that represents a quantity that the scientist modifies in an experiment. A dependent variable represents a quantity whose value depends on how the independent variable is modified. This is the variable being studied and measured.
So, an example of this applied to bacteria or viruses could be:
<u>An experiment where an antibiotic is tested against bacteria</u>. The antibiotic can vary in its concentration, different amounts are applied to a sample of bacteria to see if it is affected by the action of the antibiotic and if so, in what concentration. So, the independent variable is the concentration of antibiotic while the dependent variable is the survival (or not) of the bacteria.
To complete the experiment, an antibiotic whose effect is already known can be used as a positive control. That is, it is already known to kill the bacteria. And as a negative control you can simply use water, which has no effect and is known not to kill the bacteria. In this way, we validate the results and make sure that there is not something else that is affecting the bacteria and that only the antibiotic being studied has an influence.