NONVASCULAR PLANTS Nonvascular: These plants lack vascular tissue totransport water and nutrients. They rely on simple diffusion to move water, and mustlive in a moist environment. Cannot grow very tall because they lack vasculartissue. Lack true roots, stems, or leaves. Some haveroot-like structures called rhizoids Includes Mosses, Liverworts, and Hornworts
NONVASCULAR PLANTS Life Cycle: The gametophyte is the dominant generation Does not utilize seeds, but uses wind blownspores to disperse the offspring. Flagellated sperm requires water to reach andfertilize the egg; another reason why they mustlive in a moist area.
VASCULAR PLANTS Vascular plants have specialized structures: Roots, stems, and leaves Differentiated tissues: meristematic, ground,vascular, and dermal tissues. Can grow much taller than nonvascular plants dueto their vascular structures. The life cycle has a dominant sporophytegeneration, in contrast to the dominantgametophyte in nonvascular plants
TISSUES Vascular plants have differentiated tissues thatperform separate but important functions. Meristematic Tissue: consists of cells that grow anddivide repeatedly. Vascular Tissue: these cells form the xylem andphloem that transport water and nutrients Ground Tissue: has cells that are rich in chloroplastsand conducts photosynthesis Dermal Tissue: these cells protect the vascularstructures of the plant.
MAIN PLANT PARTS Roots Stems Leaves All of these parts contain dermal vascular and groundtissues.
THE ROOTS Functions: Anchoring Absorption Storage Structure: Root Hairs – increase the surface area for moreabsorption Zone of Elongation Meristematic Zone – part of the root tip where cellsgrow and divide to extend the root. Root Cap – protects the root tip
STEM Function: Connects the roots to the leaves andacts as the plumbing for the plant Structure: Xylem: One way Transports water and minerals upward Stiff, thick walls Phloem Two way Transports products of photosynthesis and water up and down Perforated walls
LEAF STRUCTURE Cuticle – waxy and water repellent. Excreted bythe epidermis Epidermis - outer layer of cells Palisade Mesophyll – elongated cells that containa lot of chlorophyll Spongy Mesophyll – Round irregular cells thatallow for gas exchange Stoma – opening in the leaves for water and gasmovement (more on the bottom of leaf) Guard Cells – “Guard” the stoma to open andclose it. Vein – contains the xylem and phloem for the leaf.
SEED VASCULAR PLANTS Gymnosperms: Ginkgos, Gnetales, cycads, and conifers “naked seeds” that are not enclosed in aprotective structure. The ovule normally developson the surface of a scale (cone) or at the tip of amodified leaf. Conifers are the most abundant gymnospermsand include pine trees Life Cycle: The Sporophyte is the dominantportion of the life cycle.
SEED VASCULAR PLANTSAngiosperms The most diverse group of land plants. “Flowering plants” - the ovule developsinside a protective ovary. The matureovary becomes a fruit. Life Cycle: The sporophyte is dominant.Double fertilization occurs to produce anendosperm, the food supply, and azygote.
SEED VASCULAR PLANTS Angiosperms Two main divisions of flowering plants. Monocotyledon: Monocots One cotyledon (seed leaf) Flower parts in threes Parallel leaf veins Scattered vascular bundles Dicotyledon: Dicots Two cotyledons Flower parts in fours and fives Net-like leaf veins Vascular bundles are arranged in a ring.
SEEDLESS VASCULAR PLANTS Include whisk ferns, ferns, club mosses,and horsetails. Life Cycle: The sporophyte is dominant Use windblown spores, not seeds, to dispersetheir offspring. The sperm is flagellated and requires water toreach the egg. These plants are limited to moist areas
BRAIN BREAK Stretch! 2 minutes Push-up/sit-ups Grab a partner Do as many push ups or sit ups as you can while yourpartner counts for you 4 minutes Switch and count your partners push ups and sit ups! 4 minutes