Plantlike photosynthesis that releases O2 occurs in a. cyanobacteria. b. archaea. c. gram-positive bacteria. d. chemoautotrophic bacteria.

Key Concepts

Photosynthesis

Photosynthesis is the biological process by which green plants, algae, and some bacteria convert light energy into chemical energy, using carbon dioxide and water to produce glucose and oxygen. This process is essential for life on Earth as it provides the primary energy source for nearly all ecosystems and contributes to the atmospheric oxygen levels.

Cyanobacteria

Cyanobacteria, often referred to as blue-green algae, are a group of photosynthetic bacteria that can perform oxygenic photosynthesis. They are significant contributors to the Earth's oxygen supply and are known for their ability to thrive in diverse environments, including extreme conditions. Their role in the evolution of life on Earth is crucial, as they were among the first organisms to produce oxygen.

Chemoautotrophy

Chemoautotrophy is a metabolic process where organisms obtain energy by oxidizing inorganic substances, such as hydrogen sulfide or ammonia, rather than through photosynthesis. Chemoautotrophic bacteria play a vital role in nutrient cycling, particularly in environments devoid of sunlight, but they do not produce oxygen as a byproduct, distinguishing them from photosynthetic organisms.