Question

Marine planktonic diatoms are responsible for up to 20% of primary production on earth, fixing more than 10 billion tons of inorganic carbon each year. The existence of both the C3 and C4 pathways were recently discovered in a marine diatom. In this unicellular organism, the two paths are kept separate by having the C4 path in the cytosol, and the C3 path confined to the chloroplast. What are the evolutionary implications of this discovery?

A. Adaptation to changing environmental conditions
B. Enhancement of carbon fixation efficiency
C. Development of specialized metabolic pathways
D. Expansion of ecological niche

Answer 1

The evolutionary implications of the discovery of both C3 and C4 pathways in marine diatoms include improved adaptation to environmental changes, enhanced carbon fixation efficiency, specialized metabolic pathway development, and potential expansion of their ecological niche.

Step-by-step explanation:

The discovery of both the C3 and C4 photosynthetic pathways in a marine diatom has significant evolutionary implications. These pathways allow the organism to efficiently fix carbon, an essential process for global ecology and the aquatic food chains. The C4 pathway being located in the cytosol and the C3 pathway within the chloroplast suggests an evolutionary adaptation that may enhance the diatom's ability to adapt to changing environmental conditions, potentially expanding its ecological niche and improving its competitive advantage over other phytoplankton. This could also signify the development of specialized metabolic pathways to optimize carbon fixation efficiency under various environmental pressures. Consequently, such evolutionary advancements have likely contributed to the prominence of diatoms in marine ecosystems and their vital role in the carbon cycle.