The ancestors of modern ________ performed the oxygenic photosynthesis responsible for converting our anoxic planet to an oxygenated one.

A. Firmicutes
B. Cyanobacteria
C. Crenarchaeota
D. Proteobacteria


Answer: B

Biology & Microbiology

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Photosynthetic organisms provide ____ to ecosystems

a. provisioning services b. regulating services

c. nutrient cycling d. hybridization e. support services

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What organic molecules likely existed before the first cell?

A. nucleic acids B. lipids C. All answers are correct. D. proteins E. carbohydrates

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An organism lives in water and can best be viewed using a microscope. It often reproduces asexually by budding, has no cell walls, and obtains energy by eating other organisms. Into what kingdom would you classify this organism?

a) Fungi b) Protista c) Plantae d) Animalia

Biology & Microbiology

When e-cadherin expression ___ this increases invasiveness of tumor cells.

a. increased b. decreased c. stays the same d. none of the above

Biology & Microbiology