The Land Plants: Adaptation for Terrestrial life

Announcements There will be a quiz next lab period Assigment for this lab include page 113, 114, 115,116, 117, 118

This Lab Land plants Mosses Ferns Conifers Angiosperms Dissecting Cassia and Lily

Land plants Ferns mosses Conifers angiosperms Green algea Terrestrial Embryo (young dormant sporophyte) Dominant sporophyte Vascular system with tracheids seeds Secondary growth Flowers Vascular plants Seed plants

Land plants * Plants photosynthetic eukaryotes that uses chlorophylls, store carbohydrates, usually as starch, and develop from embryo protected by tissues of the parent plant (embryophytes). * Plant life cycle N organism 2N organism mitosis gametes zygote syngamy meiosis spores mitosis sporophyte gametophyte

Land plants * 12 phyla exist nontracheophytes (nonvascular or bryophytes) 1-The persistent generation is the gametophyte (dominant) 2-Sporophytes are very short-lived, are attached to and nutritionally dependent on their gametophytes and consist of only an unbranched stalk, or seta, and a single, terminal sporangium 3-bryophytes never form xylem tissue, the special lignin-containing, water-conducting tissue that is found in the sporophytes of all vascular plants

Nontracheophytes 1- Mosses *hydroids for water and leptoids for nutrient *dependance on water for sexual reproduction * Antheridia (sperm producing structures) and Archegonia (egg producing structures)at the apex of gametophyte *calyptra is the enlaged archegonium containing the zygot *sporophyte is composed of foot, stalk (seta) and sporangium (spores containing capsule) *germinating spore grow into young gametophyte ( protonema )

Mosses

Nontrcheophytes 2- Hornworts 3- liverworts

Trcheophytes 1- vascular system with tracheids 2- sporophyte phase is dominant 3- seeds which is embryos protected in a seed coat and supplied with additional nutrition 4- secondary growth in a ring around stems (shoot meristems) and roots (root meristems) with the production of wood (shoot meristems)

Vascular system * It is plant tissue consisting of cells joined into tubes that transport water and nutrients throughout the plant body (in all but bryophytes). *xylem is the tube-shaped, nonliving portion of the vascular system in plants that carries water and minerals from the roots to the rest of the plant. *Phloem is the portion of the vascular system in plants consisting of living cells arranged into elongated tubes that transport sugar and other organic nutrients throughout the plant

Ferns 1- you can recognize 4 tissue type in the vascular system thick outer cortex thick walled cells of xylem tissue made up of tracheids thin walled cells of phloem tissue inner pith 2-the rigid tracheid cell gives support in addition to water conductance 3-well developed root underground stem, rhizome 4-true leaves fronds (P.109) Not homologous to leaves of mosses 5-heart sheped gametophyte, prothallus 6- cluster of sporangia on under surface of fronds, sorus

Ferns

gametophyte stage of a fern with rhizoids Cross section of a fern stem (stained)

Conifers Pines (F.29.5) male and female (fertilized) cones sporangium is surrounded by integument naked seeds which is the mature ovule secondary growth (wood or secondary xylem)

Angiosperms Flowering plants Pollinators Seed, embryo, endosperm and seed coat (P.110) -embryo: 2n, sperm nucleus and egg -endosperm: 3n, sperm nucleus and and 2 central nuclei -seed coat: 2 integument Sepals and petals: modified leaf appendages stamens: modified male structure Carples: enclose the ovules fruit:mature carpels including the seeds pistil: femal structure receptacle: region of attachement

Angiosperms

*Monocots (palms, orchids, lilies, grasses) one embryonic cotyledon flower parts are in multiples of three parallel veins *Dicots (trees, herbs, cacti, soyabeans, sunflowers) two embryonic cotyledons flower part are in multiple of five netlike veins

Angiosperms