You Are Given Four Test Tubes, Each Containing an Unknown

question 1

Multiple Choice

You are given four test tubes, each containing an unknown protist, and your task is to read the following description and match these four protists to the correct test tube.
When light, especially red and blue light, is shone on the tubes, oxygen bubbles accumulate on the inside of test tubes 1 and 2. Chemical analysis of test tube 1 indicates the presence of a chemical that is toxic to fish and humans. Chemical analysis of test tube 2 indicates the presence of substantial amounts of silica. Microscopic analysis of organisms in test tubes 1, 3, and 4 reveals the presence of permanent, membrane-bounded sacs just under the plasma membrane. Microscopic analysis of organisms in test tube 3 reveals the presence of an apicoplast in each. Microscopic analysis of the contents in test tube 4 reveals the presence of one large nucleus and one small nucleus in each organism.
Test tube 2 contains ________.

• A) Paramecium
• B) Pfiesteria (dinoflagellate)
• C) Entamoeba
• D) Triceratium (diatom)

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Definitions:

Transmission

The act or process of transferring something from one place, person, or thing to another, often used in the context of diseases, information, or genetic traits.

Parasites/pathogens

Organisms that live on or in a host organism and cause harm or disease to the host.

Endogenous Retroviruses

Viral sequences in the genome that result from ancient viral infections in the lineage of a species, now transmitted vertically from parent to offspring.

Coevolved

The process by which two or more species influence each other's evolutionary pathway, often resulting in mutual adaptations.