Intro to Agriculture AAEC – Paradise Valley Fall 2014 PLANT ANATOMY & FUNCTION

Why are plants important? Provide oxygen Prevent famine – MAJOR FOOD SOURCE Provide medicine

How are plants used in agriculture?  Crops Cereal Grains - wheat, rice  Ornamental Landscape design - indoors and outdoors  Medicine Biotechnology, possible cures

What are 5 major parts of a flowering plant? Leaves Stems Roots Flower Fruit

Why are leaves important? Collect light Site of photosynthesis Main site of transpiration

What are the parts of a leaf? Blade: helps with collecting the sun’s rays Veins: transport water and nutrients midrib: central vein Petiole: point of attachment to the stem Nodes: will grow if the petiole is removed

Why is the stem important? Produce and support new leaves Transport water and nutrients to and from the roots Storage of nutrients

What are the parts of a stem? Terminal bud: point of new growth Lateral bud: point of new growth Internode: in- between points of growth Leaf scar Bud scale scar

What are the parts of a root? Primary root: the first root to grow Secondary roots: branch off of the primary root Root hairs: these account for 95% of water absorption

Why are the roots important? Provide anchor for the plant Absorb water and nutrients Storage of nutrients and water

What are the three types of roots? Taproot: absorbs water deep in the ground - carrots, pecan trees Fibrous roots: roots stay close to top soil - tomato, bedding plants Adventitious: helps plant climb or anchor - ivy, strawberries, some grasses.

Comparing Stems and Roots

Why are flowers important to the Plant? Flowers serve as the reproductive organ of the plant

Parts of a Flower

Parts of the Flower Stamen – Male part of the flower Anther – pollen-producing structure Filament – stalk that supports the anther

Parts of a Flower

Parts of the Flower Pistil – Female part of the flower Stigma - place where sticky pollen grains are deposited Style - tube where the pollen grains travel from the stigma to the ovary Ovary - base of the pistil, where the pollen germinates with the ovules, this becomes the fruit Ovules - individual eggs, these are the plant seeds

Parts of a Flower

Parts of the Flower Petal – modified leaves that serve to attract insects for pollination Sepal – protects the inner parts of the flower bud from rain, mechanical injury and insects Receptacle – the base where all the flower structures are attached

Parts of a Flower Receptacle

Why is Fruit important to plants? The site of seed production, fruit also plays a role in the dissemination of the seeds