BSC 2011 Lecture Notes - Lecture 3: Synapomorphy, Charophyta, Red Algae

• School: University of Florida
• Department: Biology - Biological Sciences
• Course: BSC 2011
• Professor: Norman Douglas, Jennie De Marco, Keith Choe

Document Summary

All plants before land plants were aquatic organisms. All plants have chloroplasts derived from primary endosymbiosis involving cyanobacteria and all plants have chlorophyll a. Microscopic freshwater algae forming sister group to plantae. Have chloroplasts that have retained their peptidoglycan cell walls. Peptidoglycan is a polymer that forms a meshlike structure outside bacterial cell walls- surrounds and protects bacteria. Red algae and green plants lost peptidoglycan marker, thus distinguishing from glaucophytes. Red color comes from phycocerythrin (accessory pigment which absorbs green light to extend photosynthetic range) Chloroplasts contain chlorophyll a and carotenoids but not chlorophyll b. Monophyletic group composed of green algae and land plants. Chlorophytes, coleochatophytes, charophytes, green algae and land plants. Key synapomorphies of the clade: chlorophyll b as well as chlorophyll a, starch- sugars stored as true starch. Definition of green plant: chloroplasts developed from primary endosymbiosis, chloroplasts with both chlorophyll a and b, carbohydrates stored as starch.