You Are Looking at a Sample from the Top Green

question 54

Multiple Choice

You are looking at a sample from the top green layer of a colorful bacterial mat. Using phase contrast and fluorescence microscopy, you see evenly spaced cells in the middle of a filament that are slightly smaller than the others. The smaller cells are not fluorescent, indicating they lack photosystem II, but the rest of the filament is fluorescent. What is the most likely function of the smaller cells in the filament?

• A) survival in the dark
• B) nitrogen fixation
• C) sulfur storage
• D) nitrate storage

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Definitions:

Blood Fluke

A type of parasitic worm, belonging to the schistosomiasis family, that infects the blood vessels of the intestinal tract or urinary tract in humans.

Beef Tapeworm

A parasitic flatworm, Taenia saginata, which infects humans through consumption of undercooked or raw beef.

Life Cycle

The series of stages through which a living organism passes, from its inception to the generation of new individuals.

Inguinal Hernia

A condition where soft tissue, often part of the intestine, protrudes through a weak point in the abdominal muscles near the groin area.