BI111 Chapter Notes - Chapter 33.3: Tracheid, Gametophyte, Double Fertilization
Document Summary
The evolution of xylem and phloem gave advantages like size and hydration. Vascular plants can be divided into two groups; lycophytes and ferns and horsetails. Rhynie cherts provide a window into the early evolution of vascular plants: Rhynie cherts provide our best view of early vascular plants. Plants evolved to have the same upright stature because the evolution of vascular tissue. Lycophytes are the sister group of all other vascular plants: Lymphocytes are the earliest branching group of vascular plants and are the sister group to all other vascular plants. Ancient lycophytes included giant trees that dominated coal swamps about 320 million years ago: Swamps that formed years ago were dominated by tree-sized lycophytes. Giant lycophytes relied on thick bark for mechanical support. Dead trees left coal deposits as they decayed. These forest giants were outcompeted by seed plants. Ferns and horsetails are morphologically and ecologically diverse: Photosynthetic surfaces are divided into smaller units called pinnae.
