Question

You live in a city in Florida on the Gulf of Mexico and are trying to figure out why the water at the beaches turned bright green for several months during the summer. You discover the green comes from a photosynthetic organism that grew at great numbers due to fertilizer spill in a nearby river. You have isolated the organism and are now testing its DNA. You extract all the DNA from your sample and find that there are three distinct kinds of DNA. Which of the following organisms could have been responsible for the bloom: fungus, bacteria, or protist? How do you know?

Answer 1

The organism responsible for the bright green water at beaches is most likely a protist, indicated by the presence of three distinct kinds of DNA in the sample, which is typical for protists.

Step-by-step explanation:

Based on the information provided, the green water at the beaches likely indicates a photosynthetic algal bloom. The presence of three distinct kinds of DNA in the isolated sample suggests that the organism responsible for the bloom is likely a protist. This inference is made because different types of DNA correspond to different components within protist cells, such as nuclear DNA, mitochondrial DNA, and in some cases, chloroplast DNA. Such a DNA organization is not typical of fungi or bacteria. Fungi are heterotrophic and would not be expected to have a photosynthetic pigment, while bacteria would typically have a single circular chromosome and not three separate kinds of DNA. Protists, particularly algae, are known for photosynthetic capability and have been linked to massive blooms in aquatic environments due to nutrient runoff, such as a fertilizer spill.

The organism responsible for the green bloom in the Gulf of Mexico beaches is most likely a protist. The presence of three distinct kinds of DNA indicates genetic variability within the organism, which is characteristic of many protists. Protists are eukaryotic microorganisms that can perform photosynthesis and are known to cause algal blooms when conditions are favorable, such as an increase in nutrients from a fertilizer spill in the nearby river.

Answer 2

Blue-green algae affect freshwater, and it has a direct correlation to agricultural and urban runoff.

The heavy rains last spring most likely caused Lake Okeechobee to discharge water containing blue-green algae into rivers and canals. The bright green sludge oozed onto docks, dams and rivers and through tributaries into the ocean.

Blue-green algae (cyanobacteria) are a group of prokaryotic, autotrophic microorganisms that contain the photosynthetic pigments (chlorophyll and phycocyanin), Therefore, the DNA shows bacteria

Bacteria is the correct answer