BIOL 100 Lecture Notes - Lecture 20: Zygote, Plant, Multicellular Organism
Document Summary
Distinguish between bryophytes, vascular plants, gymnosperms, and angiosperms. Multicellularity might have origin in cooperation- beneficial adaption of organisms. Advantages: division of labor, more gas exchange, respiration (better surface to volume ratio, organisms grow larger, damaged cells repaired. Plantae are multicellular photosynthetic eukaryotes with cellulose in walls. Within xylem- lignin: complex polymer that strengthens the cell walls in vascular tissue. Modification in vascular tissue evolution to seedless vascular plants. Each plant has vascular tissue, pollen, seeds, flowers. Vascular plants- have vascular tissue, which transports water and nutrients in plant. Bryophytes (mosses)- plants with no vascular tissue, seeds or flowers, require water for reproduction. Angiosperms (cased seed)- flowering plants, fruits introduced to new reproductive adaptations. Dormant, protected plant embryos with nutrient supply. Can travel far from parent and germinate when conditions are good. Similarity among plant life cycles is evidence that plants share common ancestor. Alternation of generations: plant life cycle, multicellular diploid stage. What are lichens? alternates with multicellular haploid stage.
