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The plant kingdom. Chapter 8 Section 1. What is a plant?. Autotrophs Organisms that produce their own food Eukaryotes Cells contain a nucleus Surrounded by cell walls Photosynthesis Sun-powered, food-making factory Multicellular Organized into tissues. Plant Cell. 1. 2. 4. 5. 3.
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The plant kingdom Chapter 8 Section 1
What is a plant? • Autotrophs • Organisms that produce their own food • Eukaryotes • Cells contain a nucleus • Surrounded by cell walls • Photosynthesis • Sun-powered, food-making factory • Multicellular • Organized into tissues
Plant Cell 1 2 4 5 3
Adaptations for living on land • Algae… • Plants living on land… • Must have ways to obtain water and other nutrients • Retain water • Transport materials in their bodies • Support their bodies • Reproduce
Obtaining water and other nutrients • Obtain water and other nutrients from soil (adaptation)
Retaining water More water in the PLANT CELLS than in the AIR= water leaves the plant and enters the air • What is a plants adaptation to reduce water loss? • CUTICLE • a waxy, waterproof layer that covers the leaves of most plants
Transporting materials • Water and minerals are taken UP by the bottom part of the tree • Food is made in the top part and brought DOWN • Vascular Tissue • A system of tubelike structures inside a plant through which water, minerals, and food move • Smaller plants—can simply move from one cell to the next
WATER AND MINERALS FOOD
support • Rigid cell walls and vascular tissue strengthen and support larger plants • Smaller plants can support themselves
REPRODUCTION • Plants undergo sexual reproduction • Fertilization • Joining of sperm cell with egg cell • Zygote • Fertilized egg
Classifying plants • Nonvascular plants • Vascular plants
Nonvascular plants • Lack a well-developed system of tubes for transporting water and other materials • Low-growing • No roots • Obtain water directly from surroundings • Slow process • Live in damp, shady areas
Vascular plants • Have a well-developed system of tubes for transporting water and other materials • Provide • Strength • Stability • Support • Plants are able to grow quite tall
Origin of plants • Biologists studied fossils • Oldest plant fossil are about 400 million years old • Plants and green algae contain the same form of chlorophyll • This evidence led biologists to infer that ancient green algae were ancestors of today’s plants
Complex life Cycles • Sporophyte stage • The plant produces spores, tiny cells that can grow into new organisms • Gametophyte stage • The plant produces two kinds of sex cells: sperm cells and egg cells