The Plant Roots 4 The function of the plant’s roots are to absorb nutrients and water from the soil and to anchor the plant. 4 The root system can makeup 50% of a plants weight.
4 There are two types of root systems soilless roots which include aerial (ivy), and aquatic(water lily). 4 Soilborne roots are classified into tap and fibrous roots.
4 Tap roots are those roots which have a long main root such as a carrot or pine tree. 4 Fibrous roots spread out such as grass
Parts of the Root 4 At the tip is the roots cap, where cell division occurs and it pushes down into the soil. 4 Root hairs are used to help take in nutrients
The Plant Stem 4 The major function of the stem is to join the root and leaf systems. 4 Some photosynthesis also takes place in the stem.
Parts of the Stem 4 Node- jointed part of the stem on which leaf or flower buds develop 4 Internode- major part of the stem between the nodes.
4 Axillary Bud- bud found at the leaf axil from which flowers and branches arise. 4 Terminal Bud- tip or end of the shoot were growth takes place.
4 Petiole- is a stem-like leaf structure that attaches the leaf to the stem
Woody Stems 4 Outerbark- protects the interior of the plant from insects and diseases and excessive heat and cold. 4 Innerbark- carries food manufactured in leaves to the branches, trunk, and roots
4 Cambium- layer of cells between the bark and wood where growth is diameter occur and the formation of annual rings.
4 Sapwood(xylem)- carries sap from the roots to the leaves 4 Heartwood- is inactive sapwood which is darker in color and gives strength to the plant
4 Pith- is the dark center in the heartwood core.
Leaves 4 Leaves are the food factory of the plant producing all food that is used by the plant and stored for later use by the plant or by an animal. 4 Leaves vary in shape and size; with most of them being flat 4 The arrangement of the leaves differ alternate, opposite, whorled,
External Leaf Structures 4 The petiole is the stalk that attaches the leaf to the stem 4 The blade which is the flat part of the leaf 4 The midrib which is the large center vein from which all veins extend 4 The margins which are the edges of the leaf
Internal Leaf Structures 4 The skin of the leaf is called the epidermis which is a single layer of cells. The epidermis provides protection from water loss. 4 The guard cells open and close a small space or pore on the underside of the leaf called the stoma 4 The stoma allows the plant to transpire. This gives off moisture and exchange of gases.
4 In the inner part of the leaf are the chloroplast. The chloroplast are filled with chlorophyll which give the leaf it’s green color. 4 With the use of chlorophyll, minerals, sugars sunlight and carbon dioxide the plant goes through photosynthesis
4 The formula for photosynthesis is the following: 4 6CO2 + 6 H2O + 672 Kcals (light energy) = C6H12O6 (Glucose) + O2
Flower 4 The purpose of the flower is the reproduction of the plant. This can be done through fruits and seed. 4 The reason flowers are colorful is to attract insects for pollination
Parts of the Flower 4 The sepals are the green leaflike part of the flower located at the base and are used to protect the flower bud. 4 The petals are actually leaves and are the most striking part of the flower 4 The stamen makes up the male reproductive part of the plant. This includes the anther which holds the pollen. The filament is the slender stalk that holds the anther
4 The pistil is the female reproductive part of the flower. This includes the stigma which is sticky and catches the pollen, the style which is a long tube that carries to the ovary, the ovary is where the egg is produced.
4 A complete flower has both male and female parts 4 An incomplete flower contains only one of the parts