Plants Plant Characteristics What are the characteristics of

Plants

Plant Characteristics • What are the characteristics of a plant? • Eukaryotic cells (cells have a nucleus) • Multicellular • Have cell wall made of cellulose (sugar) • Autotrophic (get food from photosynthesis) • Reproduce sexually or asexually

Vascular v. Non-vascular Plants • What are 2 main groups of plants? • What are the traits of non -vascular plants? • Non-vascular • Vascular • They do NOT have special tissues that carry water or nutrients through the plant • They are very small • Use osmosis to take in water • Live in shady moist places

Plant Tissues • What are traits of vascular • Contains special tissues plants called xylem and phloem that carry water and nutrients • They are large plants • Some have flowers (angiosperms), some don’t (gymnosperms) • What is xylem? • Hollow tubes that carry water up from the roots to the leaves

Plant Tissues • What is phloem? • Hollow tubes that carry sugar down from the leaves to the roots

Plant Parts • What are the main parts of a plant? • What are the functions of the roots? Roots Stems Leaves Absorb water and nutrients for the plants • Hold the plant to the ground • Store extra food for the plant. Plant food is starch (a polysaccharide) • •

Plant Parts • What are the functions of stem? • What are the functions of the leaves? • Supports the plant • Carries nutrients, glucose, and water • Gets leaves closer to the sun • PHOTOSYNTHESIS!! • Transpiration • Gas exchange

Plant Parts • What is photosynthesis? • What is transpiration? • What are stomates (stomata)? • A process that uses sunlight to convert CO 2 and H 2 O into glucose • It occurs in the chloroplasts (plant cells only) • The loss of water and CO 2 through the stomates (stomata) of a leaf • Openings on the underside of a leaf that allow CO 2, H 2 O and O 2 to enter and leave the leaf

stomate Guard cell

Plant Parts • What is involved in gas exchange? • Movement of CO 2, H 2 O and O 2 into and out of a leaf • Occurs through stomata (stomates) • The transport that moves Oxygen and Carbon Dioxide is Diffusion. • The transport moving water is Osmosis and Capillary Action

Transport of Water • Osmosis • Passive Transportrequires no energy. • Moves with the concentration gradient (high to low) • Plants prefer Hypotonic • Water is stored in the central vacuole • Capillary Action • Helps move water through the Xylem and out the stomata • It is the water molecules will be attracted to each other and the walls of the tube causing the level to rise.

Plant Parts • What are the parts of a leaf? • Cuticle-waxy covering on the top of the leaf that helps it retain water • Epidermis-the skin of the leaf; blocks pathogens (disease causing stuff) • Mesophyll-cells where photosynthesis occurs • Vascular tissue-xylem and phloem

Plant Reproduction • What are the parts and functions of a flower • The function: attract pollinators, produce pollen (sperm), and ovules (eggs) • Male parts (stamen) – Pollen; the part of flower that contains sperm cells – Anther; the part of the stamen that makes pollen – Filament; a long stalk that hold up the anther

Boy parts anthers stamen filament

anther filament More boy parts

Plant Reproduction • What are the parts and functions of a flower? • Female parts (pistil) – Stigma; the sticky tip of the pistil where the pollen attaches – Style; the long tube connecting the stigma to the ovary; sperm travel down this tube – Ovary; the swollen part at the bottom of the pistil that contains the ovules – Ovules; eggs

stigma style Pistil Girl parts anthers

Ovary ovules

Plant Reproduction • What are the parts and functions of a flower? • Accessory parts (not male or female) – Petals; usually brightly colored; attract insects for pollination – Sepal; usually green; protects the flower while it’s developing – Receptacle; bottom of the flower that holds all the parts together

receptacle sepals

Plant Reproduction • Pollination • Fertilization • The transfer of sperm from the anther to the stigma • The uniting of sperm and egg

Plant Responses • How do plants respond to the environment? • Hormones control • What are auxins? • Plant hormones that control – Patterns of growth – Responses to environment – Phototropism – Gravitropism – Branching

Tropisms (turning) • What is phototropism? • The tendency of a plant to bend toward a light source

Tropisms (turning) • What is gravitropism? • The response of a plant to the force of gravity – Stems grow up – Roots grow down

Tropisms (turning) • What is thigmotropism • The response of a plant to touch – Vines curl around a trellis – Sensitive plant closes its leaves when touched – Venus fly trap