Photosynthesis Photosynthetic Organisms 2

Question 1

Which group of bacteria performs oxygenic photosynthesis and is credited with oxygenating Earth's early atmosphere?

Accepted Answer

Cyanobacteria

Answer

Cyanobacteria were the first organisms to perform oxygenic photosynthesis, releasing O2 as a byproduct and transforming Earth's atmosphere.

Question 2

What is the primary photosynthetic pigment in brown algae (phaeophytes)?

Accepted Answer

Fucoxanthin

Answer

Fucoxanthin is the dominant accessory pigment in brown algae, giving them their characteristic brownish color.

Question 3

Which photosynthetic organisms form symbiotic relationships with fungi to create lichens?

Accepted Answer

Algae or cyanobacteria

Answer

Lichens are mutualistic associations where algae or cyanobacteria provide photosynthate to fungi, which provide shelter and moisture.

Question 4

Euglenoids are unique photosynthetic protists because they:

Accepted Answer

Can switch between autotrophy and heterotrophy

Answer

Euglena can photosynthesize in light and consume organic matter in darkness, making them mixotrophic organisms.

Question 5

Which terrestrial plants are considered the most evolutionarily primitive photosynthetic land plants?

Accepted Answer

Liverworts and mosses (bryophytes)

Answer

Bryophytes (mosses, liverworts, hornworts) were among the first plants to colonize land and lack vascular tissue.

Photosynthesis Practice Test