Answer:
The fourth plant that receives pure water is the control group.
Explanation:
The election of a control group is essential in an experiment. Its principal purpose is to allow the discrimination of the results obtained by the treatment in the study, in this case, <em>the different concentrations of salty water that each plant receives</em>. The control group provides a reference point. It must be selected from the same population of the treatment groups. Both groups must be similar in every variable that might influence the results, <u>except for the study treatment.</u>
Answer:
As light intensity increases (distance between lamp and plant decreases) the volume of oxygen (or the rate of bubble production) increases. This indicates that the rate of photosynthesis increases with light intensity. However, at sufficiently high levels of light intensity, the rate oxygen evolution remains constant.
<span>Leukocytosis is an increase in the number of white blood cells whereas Leukopenia is an abnormal reduction of white blood cells, giving rise to a significant immune-suppression.</span>
The answer is D, algae.
—Evidence—
•] Protozoan definition: a single-celled microscopic animal of a group of phyla of the kingdom Protista, such as an amoeba, flagellate, ciliate, or sporozoan.
•] it does not feature algae, therefore it’s D.
Longitudinal waves move parallel to the direction of wave motion.
Transverse move perpendicular.
