20.
They told me that my answer was too short so I'm just adding this on, don't mind me.
Answer:
The correct answer is option C) "More than one variable is being tested".
Explanation:
One of the basis of scientific experimentation is to test one variable at the time in order to make sure that the response that is being obtained is the result of that variable and not another one that is not taking into account. In this case, the student is making the mistake of assessing two variables at the same time: the use of detergent and placing the plant in the sun or in the shade. At the end of the experiment the student will not know if the response is the effect of the detergent, the exposure to the sun or a combination of both.
Answer;
-Flagellum (flagella; plural)
Explanation;
-Prokaryotes are single-celled organisms belonging to the domains Bacteria and Archaea.
-A flagellum is a whip-like structure that allows a cell to move. They are found in all three domains of the living world: bacteria, archaea, and eukaryota, also known as protists, plants, animals, and fungi.
-The primary role of the flagellum is locomotion, but it also often has function as a sensory organelle, being sensitive to chemicals and temperatures outside the cell. Flagella are organelles defined by function rather than structure. Flagella vary greatly. Both prokaryotic and eukaryotic flagella can be used for swimming but they differ greatly in protein composition, structure, and mechanism of propulsion.