Introduction to the Plant Kingdom copyright cmassengale

Aquatic to Terrestrial Life Early Ancestors Aquatic to Terrestrial Life copyright cmassengale

copyright cmassengale Aquatic Ancestor green algae Chara copyright cmassengale

Algae & Land Plant Similarities Both contain chlorophylls a and b Have chloroplasts with stacks of thylakoids Store starch in plastids Cellulose in cell walls Go through Alternation of Generations life Cycle copyright cmassengale

copyright cmassengale Aquatic Habitat Terrestrial Habitat copyright cmassengale

Living in Aquatic Environments Plants surrounded by water so don’t dry out Sperm swims to egg Water supports plant Plants stay in upper surface near light Absorb nutrients from the H2O copyright cmassengale

Plant Adaptations to Land Solutions: Roots absorb H2O & minerals Lignin & cellulose in cell walls Vascular Transport System Waxy cuticle & stomata with guard cells Pollen containing sperm Problems: Need minerals Gravity Increase in Height for Light Adaptations for Drier environment Reproduction copyright cmassengale

How Are Plants All Alike? copyright cmassengale

Plant Characteristics Multicellular Autotrophic (photosynthesis) Chlorophylls a and b in thylakoid membranes Surrounded by cell walls containing cellulose (polysaccharide) Store reserve food as amylose (starch) copyright cmassengale

copyright cmassengale Plant Reproduction Alternation of generations life cycle Diploid (2n) sporophyte stage Haploid (1n) gametophyte stage Produce multicellular embryo protected inside multicellular haploid (gametophyte egg sac) tissue copyright cmassengale

copyright cmassengale Plant Reproduction Diploid (2n) sporophyte stage produces haploid spores by meiosis Haploid spores undergo mitosis to produce gametophyte stage Gametophyte makes gametes (eggs and sperm) by meiosis Zygote (2n) produces the new sporophyte copyright cmassengale

Alternation of Generations Gametophyte 2n Sporophyte 2n gametophyte 1n pollen 2n seed with plant embryo Ovary with 1n ovules (eggs) Sporophyte copyright cmassengale

copyright cmassengale Plant Divisions copyright cmassengale

copyright cmassengale Taxonomy Plants are divided into two groups Based on the presence or absence of an internal transport system for water and dissolved materials Called Vascular System Vascular Bundles copyright cmassengale

copyright cmassengale Vascular System Xylem tissue carries water and minerals upward from the roots Phloem tissue carries sugars made by photosynthesis from the leaves to where they will be stored or used Sap is the fluid carried inside the xylem or phloem copyright cmassengale

Nonvascular Plants Do not have vascular tissue for support or conduction of materials Called Bryophytes Require a constantly moist environment Sporophyte stage Gametophyte Stage Moss Gametophytes & Sporophytes copyright cmassengale

copyright cmassengale Nonvascular Plants Plants can’t grow as tall Cells must be in direct contact with moisture Materials move by diffusion cell-to-cell Sperm must swim to egg through water droplets copyright cmassengale

copyright cmassengale Nonvascular Plants Includes mosses (Bryophyta), liverworts (Hepatophyta), and hornworts (Antherophyta) Liverworts Hornworts copyright cmassengale

Main Parts of Vascular Plants Shoots -Found above ground -Have leaves attached - Photosynthetic part of plant Roots -Found below ground -Absorb water & minerals -Anchor the plant copyright cmassengale

copyright cmassengale Vascular Plants Also called Tracheophytes Subdivided into two groups -- Seedless vascular plants and Seed-bearing vascular plants Club Moss copyright cmassengale

Seedless Vascular Plants Includes club moss (Lycophyta), horsetails (Sphenophyta), whisk ferns (Psilophyta), and ferns (Pterophyta) Whisk ferns copyright cmassengale Horsetails

Seed-Producing Vascular Plants Includes two groups – Gymnosperms and Angiosperms Gymnosperms have naked seeds in cones Angiosperms have flowers that produce seeds to attract pollinators and produce seeds copyright cmassengale

copyright cmassengale Gymnosperms Coniferophyta are known as conifers Includes pine, cedar, spruce, and fir Cycadophyta – cycads Ginkgophyta - ginkgo Cycad Ginkgo copyright cmassengale

copyright cmassengale Gymnosperms Contains the oldest living plant – Bristle cone pine Contains the tallest living plant – Sequoia or redwood copyright cmassengale

copyright cmassengale Angiosperms Flowering plants Seeds are formed when an egg or ovule is fertilized by pollen in the ovary Ovary is within a flower Flower contains the male (stamen) and/or female (ovaries) parts of the plant Fruits are frequently produced from these ripened ovaries (help disperse seeds) copyright cmassengale

copyright cmassengale Angiosperms Division Anthophyta Subdivided into two groups – Monocots and Dicots Monocots have a single seed cotyledon Dicots have two seed cotyledons copyright cmassengale

copyright cmassengale Monocots Parallel venation in leaves Flower parts in multiples of 3 Vascular tissue scattered in cross section of stem copyright cmassengale

copyright cmassengale Dicots Net venation in leaves Flower parts in multiples of 4 or 5 Vascular tissue in rings in cross section of stem copyright cmassengale

copyright cmassengale Plant Uses copyright cmassengale

Why We Can’t do Without Plants! Produce oxygen for the atmosphere Produce lumber for building Provide homes and food for many organisms Prevent erosion Used for food copyright cmassengale

More Reasons We Can’t do Without Plants! Produce wood pulp for paper products Source of many medicines Ornamental and shade for yards Fibers such as cotton for fabric Dyes copyright cmassengale

Additional Plant Notes copyright cmassengale

Plant Cells and Tissues Plant tissues are made of 3 basic cells types: copyright cmassengale

copyright cmassengale Parenchyma Cells most common; store starch, oils, and water; can be found throughout plant; location of photosynthesis; can divide throughout life, so impt for healing copyright cmassengale

copyright cmassengale Collenchyma Cells varying thickness of cell walls; most common in younger tissues of leaves and shoots; think of celery strings; flexible (cell walls lack lignin) copyright cmassengale

copyright cmassengale Scherenchyma Cells the strongest of the three; second cell wall hardened by lignin (tough and durable); can’t grow, so found in parts that are done growing; many die at maturity; make up the support system and water-conducting tissues copyright cmassengale

copyright cmassengale Plant Growth Meristematic tissues cause primary growth (lengthening) and secondary growth (widening) Cambium – actively growing cells that undergo mitosis Cork cambium produces bark Vascular cambium produces xylem and phloem Root caps protect the meristem tissue, and root hairs absorb water and nutrients from the soil copyright cmassengale

copyright cmassengale

copyright cmassengale Plant Growth Secondary growth of woody plants leads to ring formation. The age of a tree can be determined by counting the number of rings. Climate and other environmental conditions such as fire are also visible. copyright cmassengale

Plant Organs: Made of 3 Tissue Systems Can be made up of the 3 basic cell types, or additional cell types (dermal, ground, vascular) copyright cmassengale

copyright cmassengale Dermal Tissue System Plants’ “skin” Called epidermis Made of live parenchyma in the non-woody parts of plants Wax-coated substance is sometimes secreted copyright cmassengale

copyright cmassengale Ground Tissue System Provides support and stores materials in roots and stems In leaves- contain chloroplasts Consists of all cell types, but parenchyma is the most common copyright cmassengale

Vascular Tissue System Surrounded by ground tissue Transports water, minerals, nutrients, & organic compounds Made up of 2 networks Xylem- water and dissolved minerals Phloem- products of photosynthesis copyright cmassengale

copyright cmassengale How does water get from one point (the roots) to another (the stem or leaves)? copyright cmassengale

Cohesion-Tension Theory Think of the physical properties of water… Which vascular tissue would this take place in? copyright cmassengale

copyright cmassengale

copyright cmassengale