BIO153H5 Chapter Notes - Chapter 29: Tracheid, Microphyll, Equisetopsida
Document Summary
Plants supply oxygen and most of the food eaten by terrestrial animals and provide habitats for other organisms. Many key traits of land plants also appear in some protists: plants are multicellular, eukaryotic, photosynthetic autotrophs, they have cell walls made of cellulose and chloroplasts with chlorophylls a & b like algae. Charophytes are the only algae that share 4 distinctive traits with land plants suggesting relatedness: rings of cellulose-synthesizing proteins. Cells have circular rings of proteins in the plasma membrane. These rings make the cellulose microfibrils of the cell walls: peroxisome enzymes. They contain enzymes that help minimize loss of organic products from photorespiration: structure of flagellated sperm. Similar to that of plants: formation of a phragmoplast. Charophyte has a layer of durable polymer called sporopollenin preventing exposed zygotes from drying out. Traits allowing species to survive above water enabled descendants to live permanently above water.
