Question

Protists are microscopic organisms that are found in aquatic ecosystems. A student wonders if protists are more common at certain depths than others. After considering factors such as photosynthesis, the student hypothesizes that the surface waters of his neighborhood pond contain the greatest number of different protist species.

To test his hypothesis, the student collects several water samples from different depths in the same region of his neighborhood pond. Which data must be collected from the samples in order to address the hypothesis?
A.
the total number of all organism species in each sample
B.
the total number of protist species in each sample
C.
the total number of protist organisms in each sample
D.
all of these

Answer 1

To test the hypothesis that the greatest number of different protist species is in the neighborhood pond's surface water, the student must collect data on the total number of protist species in each sample from various depths.

Step-by-step explanation:

To address the hypothesis that surface waters of a neighborhood pond contain the greatest number of different protist species, the student should collect data on the total number of protist species in each water sample from different depths. This will specifically test the hypothesized variability in species diversity of protists with depth.

Counting the total number of all organism species (option A) or the total number of protist organisms (option C) would not isolate the data to different protist species. Hence, the correct choice is B: the total number of protist species in each sample. Protists, being varied in their habitats and ranging from microscopic to macroscopic sizes, are indicators of biodiversity in different environmental conditions, including varying depths of water.