How Are Plants All Alike? copyright cmassengale
General characteristics All plants are eukaryotic, multicellular, autotrophs (producers),nonmobile, and have a cell wall.
THE SUN: MAIN SOURCE OF ENERGY FOR LIFE ON EARTH
THE BASICS OF PHOTOSYNTHESIS Almost all plants are photosynthetic autotrophs, as are some bacteria and protists Autotrophs make their own organic matter (energy) through photosynthesis Sunlight energy is transformed to energy stored in the form of chemical bonds (c) Euglena (d) Cyanobacteria (b) Kelp (a) Mosses, ferns, and flowering plants
Light Energy Harvested by Plants & Other Photosynthetic Autotrophs 6 CO2 + 6 H2O + light energy → C6H12O6 + 6 O2
copyright cmassengale Photosynthesis Uses a green pigment (cholorphyll) to capture energy from the sun to convert it to a usable form of energy. Takes place in the cholorplasts of a plant cell. copyright cmassengale
WHY ARE PLANTS GREEN?
Chloroplasts: Sites of Photosynthesis All green plant parts have chloroplasts and carry out photosynthesis The leaves have the most chloroplasts The green color comes from chlorophyll in the chloroplasts The pigments absorb light energy
The location and structure of chloroplasts LEAF CROSS SECTION MESOPHYLL CELL LEAF Mesophyll CHLOROPLAST Intermembrane space Outer membrane Granum Inner membrane Grana Stroma Thylakoid compartment Stroma Thylakoid
THE COLOR OF LIGHT SEEN IS THE COLOR NOT ABSORBED Chloroplasts absorb light energy and convert it to chemical energy Reflected light Light Absorbed light Transmitted light Chloroplast
AN OVERVIEW OF PHOTOSYNTHESIS Photosynthesis is the process by which autotrophic organisms use light energy to make sugar and oxygen gas from carbon dioxide and water Carbon dioxide Water Glucose Oxygen gas PHOTOSYNTHESIS
Food Chain
WHY ARE PLANTS GREEN? Plant Cells have Green Chloroplasts The thylakoid membrane of the chloroplast is impregnated with photosynthetic pigments (i.e., chlorophylls, carotenoids).
copyright cmassengale Cellular Respiration Both plants and animals use this! Plants use this when there is no sunlight! Happens in the mitochondria of a cell. Cells release energy from food if oxygen is present. copyright cmassengale
copyright cmassengale Cellular Respiration copyright cmassengale
Cellular Respiration +Photosynthesis Keep oxygen and Carbon Dioxide levels normal! copyright cmassengale
Transpiraiton When water evaporates from tiny holes (stomata) in the leaf!
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
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
Moss Gametophytes & Sporophytes Nonvascular Plants Do not have vascular tissue for support or conduction of materials Sporophyte stage-produce spores Gametophyte stage-produce seeds. Sporophyte stage Gametophyte Stage Moss Gametophytes & Sporophytes
copyright cmassengale Nonvascular Plants Plants can’t grow as tall Cells must be in direct contact with moisture No roots! 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
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
Xylem and Phloem also provide stability, support, and strength to the plant.
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: Gymnosperm (Cone bearing plants) Angiosperm (Flowering Plants) Naked seeds in Cones Non-flowering Seeds are not enclosed in a fruit Needle-like leaves Reproductive structure=cones Example: Pine trees Flowers that produce seeds to attract pollinators to produce seeds. Seeds are enclosed in a protective layer or a fruit. copyright cmassengale
copyright cmassengale Gymnosperms Conifers (pine, cedar, spruce, and fir) cycads 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 and/or female parts of the plant Fruits are frequently produced from these ripened ovaries (help disperse seeds) 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
Parts of a Flowering plant
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Stems: Transport water and nutrients up throughout the plant Flower: Specialized reproductive structures that are often colorful to attract pollinators. Roots: Anchor plant in the ground and gather water and nutrients from the soil.
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Male reproductive structure-Stamen Female Reproductive Structure-Pistil The pistil has the STICKY stigma that is held up by the style. Stamen holds up the anther Anther produces pollen. The ovary contains the eggs. Once eggs are fertilized they become seeds and the ovary turns in to a fruit
Leaves: Contain chloroplasts and chlorophyll for photosynthesis. 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
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Roots anchor seed plants to the ground, absorb water and minerals from the soil, and sometimes store food in the form of starch. The stems carry substances between the roots and the leaves, support the plant, and hold the leaves up to the sun.
Flower Structure