Plant Organs and Tissues

Mr. RamosPlant Organs and Tissues1Introduction to PlantsThere are over 260,000 different species of flowering plants alone!

Plants are multicellular, eukaryotic organisms.Photosynthetic

Plants have a cell wall made of cellulose.

Plants take up water via capillary action.

2Plant ClassificationSeeds, VascularSeedless, VascularNonvascularAngiospermsFernsMossesGymnospermsHorsetailsLiverwortsWhisk fernsHornwortsClub mosses

Plants are classified as bryophytes and tracheophytes

Bryophytes are nonvascular.

Tracheophytes are vascular

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4Bryophytes and TracheophytesBryophytes are plants that lack specialized tissues for the transport of water. They absorb substances directly from their surroundings.Mosses, liverworts, & hornwortsTracheophytes are vascular plants. They can be seeded or seedless. Seeded: Flowering & non-flowering plantsSeedless: ferns

Vascular tissue transports water and nutrients. Phloem transports food from the leaves down to other plant partsXylem moves water and nutrients from the ground upward in the plant. 5Xylem and Phloem

6Roots Function of plant roots includeAnchoring and supporting the plantAbsorbing water & nutrients from the soilStore food and waterRoot ClassificationFibrous roots (monocots)Taproot (dicots)

7StemsStems transport materials between a plants root and its leaves and flowers. Trees have hard, rigid stems called a trunk. These plants are called woody plants. Plants with green, flexible stems are called herbaceous plants. These include grasses and garden plants.

8LeavesLeaves are the main organs that carry out photosynthesis. Photosynthesis is a process by which plants use sunlight to make food from carbon dioxide and water. Leaves have small openings called stomata where CO2 and O2 are exchanged. Guard cells open and close the stomata.

9GymnospermsGymnosperms are the woody plants.They are vascular plants that contain seeds.One way to determine the age of a gymnosperm is by counting the number of tree rings. The rings are dead xylem.

10AngiospermsAngiosperms are the flowering plants.They are vascular and contain seeds. Angiosperms can be further divided into monocots and dicots. Some flowering plants are woody: oak, cherry & walnut.

The fruits develop inside the flowers11SeedsA seed is a reproductive structure that contains a plant embryo. In flowering plants, the seed stores food in parts called cotyledon, or seed leaves.Angiosperms may have one or two cotyledons. Monocots contain one seed leaf, or cotyledon.Dicots contain two seed leaves or cotyledons.12Flower AnatomyThe male reproductive part is called the stamen.

The female reproductive part is called the pistil or carpel.

For sexual reproduction, pollen from the stamen must be transferred to the stigma.

The wind or animals can carry pollen to the stigma. This is called pollination.

13ConesCones are structures that are adapted for sexual reproduction in conifers. Male cones produce pollen & female cones produce eggs.After fertilization, a seed develops. Unlike the seeds of flowering plants, conifer seeds are not enclosed in protective fruit.

14SporesNonvascular plants, such as mosses, reproduce by making & releasing spores. A spore is a tiny, waterproof reproductive cell that can grow into a new organism if it falls on soil with the right conditions. Seedless vascular plants, such as ferns, also reproduce with spores.

15Life Cycle & ReproductionPlants have an alternation of generation.They spend half of their lives as haploids and part of their lives as diploid. A gametophyte is a haploid plant that produces haploid gametes.A sporophyte is a diploid plant that gives rise to haploid spores by meiosis. Spores grow to be gametophytes.

16Plant Life CycleSporophyte Spores GametophyteEggSpermFertilizationZygoteNNN2N2NNMitosisMitosisMitosisMeiosis17