Spencer Horticulture Curriculum 2011 PLANT ANATOMY Spencer Horticulture Curriculum 2011

Objectives Basic Parts Functions Types

Plant Parts Roots Stem Leaves Flower

Roots Anchor Plant Absorb water and minerals Translocate water and minerals to stem Store Food

Stems Translocate water, minerals and food to the leaves Support the leaves and display them to light Three parts: phloem, xylem, cambium

Leaves Make food through photosynthesis Provide site of gas exchange Store food Photosynthesis--Chlorophyll Light Energy 6CO2 + 6H2O = C6H12O6 + 6O2 Carbon Dioxide + Water = Sugar + Oxygen

Flowers Contain organs for specialized sexual reproduction Produce seeds and fruit

Types of Roots Tap Root Continuation of the primary root Ideal for anchorage

Types of Roots Fibrous Roots Many finely branched secondary roots Shallow roots cover a large area More effective absorption of water and minerals Roots hold the soil to prevent erosion

Types of Roots Aerial roots Clinging air roots Absorptive air roots Short roots that grow horizontally from the stems Roots that fasten the plant to a support Absorptive air roots

Types of Roots Adventitious Roots Develop in places other than nodes Can form on cuttings and rhizomes

Types of Roots Root hairs: Tiny one celled hair like extensions located near the tips of the roots Increased surface area Absorb water and minerals from soil

Types of Roots

Specialized Roots Corm (gladiolus, crocus) Underground Solid, fleshy, scale covered Bulb (tulips, lillies, onions) Layers of fleshy scales that overlap

Specialized Roots Tuber (potato, caladium) Food storage area Crown (african violets, ferns) Closely grouped stems or plantlets Just above ground or just below

Stems: Internal

Stem Tissues Xylem: transports water from roots Phloem: transports food from leaves Cambium: growth tissue

Stems: External

Specialized Stems Rhizomes (iris, lily of the valley) Underground stems Produce roots on the lower surface Extend leaves and flower shoots above the ground

Specialized Stems Stolon (Strawberry, airplane plant) Stem that grows horizontally above the soil surface Development similar to rhizomes

Parts of a Leaf

Leaf Types

Leaf Tissues Cuticle Waxy substance covers the leaves and stems Waterproof layer that keeps water in plants

Leaf Tissues Stomata Openings in the epidermis mainly located on underside of leaves Exchange of gases (Transpiration)

Leaf Tissues Guard Cells Two cells located on each side of stomata Open and closes stomata

Leaf Tissues Mesophyll layer Contains air and chloroplasts Site of photosynthesis and gas exchange

Leaf Tissues

Flower Parts Sepals Petals Outer covering of the flower bud Protects the stamens and pistils Petals Brightly colored Protects stamen and pistil Attracts pollinating insects

Flower Parts Stamens Male Reproductive part Anther-produces pollen Filament-supports the anther

Flower Parts Pistil Female reproductive part Ovary Stigma Enlarged portion at base of pistil Produces ovules which develop into seeds Stigma Holds the pollen grains

Flower Parts Pistil Cont’d Style Connects the stigma with ovary Supports the stigma so that it can be pollinated

Flower Parts

Flower Types Complete: have all four main parts Sepals Petals Stamens Pistils Incomplete: missing one of the four parts

Plant Parts