Question

Plants are currently considered to be part of the supergroup within Eukarya, Archaeplastida. All members of this group are photosynthetic and include unicellular, colonial, and multicellular organisms. The major groups of this supergroup are glaucophyte algae, green algae, red algae, stoneworts, and plants. Glaucophyte Algae Glaucophyte algae (Phylum Glaucophyta) are unicellular freshwater algae, and are thought to resemble a very ancient ancestor of plants. Study of these organisms gives us clues to the origin of photosynthesis within Archaeplastida. The current hypothesis for the origin of the chloroplast within this group is known as secondary endosymbiosis. According to this hypothesis, a free-living photosynthetic bacterium (a cyanobacterium) was engulfed by a eukaryotic ancestor but not digested, leaving a chloroplast with 2 membranes. This bacterium continued to live inside its new host, providing it with a constant supply of sugar. While plants photosynthesize. While the engulfed cyanobaterium provided the eukaryote with sugar, this eukaryotic cell provided the photosynthetic bacterium (which is considered a chloroplast once engulfed) the ability to break down those sugars to produce much more ATP via cellular respiration. Where a cyanobacterium can only harvest a net 2 ATP from a glucose molecule, a eukaryote with a mitochondrion can harvest a net 38 ATP! Draw a eukaryotic cell with mitochondrion engulfing a cyanobacterium. Label this process "secondary endosymbiosis." Under your final cell write, "Glaucophyte Algae."

Answer 1

Nut erd