Plants: Structure and Function

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Plants Structure and Function
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Importance of Plants

• Food
• Rice, wheat, peas, potatoes, apples, and all of
  the other fruits and vegetable that we consume

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Importance of Plants

• Medicine used to cure and treat several
  diseases
• Morphine, Codeine, and Salicylic Acid (found in
  aspirin)

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Importance of Plants

• Used to make clothes
• Cotton and Linen
• Used to make building materials
• Wood
• Paprus Reed is used to make paper
• Hemp plant is used to make rope
• Plants are used in cosmetics, perfumes, and waxes

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Ecology of Plants

• Plants can be found on land
• Plants can be found in the water

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Monocots and Dicots

• Monocots are seed bearing plants that have one
  cotyledon
• Ex. Grasses, Wheat, Oats, Corn, Rye, and Rice
• Dicots are seed bearing plants with two cotyledon
• Ex. Maple Trees, Cacti, and most Forest Trees

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Cotyledon

• Cotyledon are seed leaves found in the embryo

Monocot
Dicot
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Structures Roots

• Roots
• Function anchors plants into the ground,
  absorbs water and minerals, and stores food
• Types of Roots
• Tap Root
• Fibrous Root
• Prop Root

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Roots

• Tap Roots
• A primary root that does not branch off
• Usually grows large
• A single root
• Ex. Carrots, Radishes, Beets

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Roots

• Fibrous Roots
• Extensive network or branching roots
• Ex. Grasses, Orchids

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Roots

• Prop Roots
• Supports the stem
• Grows above ground
• Ex. - Corn

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Roots

• Structures
• Pith center most part of the root
• Vascular Bundles contain the xylem and phloem
• Xylem carries water and minerals
• Phloem carries sugar

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Roots

• Structures
• Endodermis layer or cells outside of the
  vascular bundle
• Cortex layer of cells found outside of the
  endodermis

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Roots

• Structures
• Epidermis outer most layer of cells
• Root Hairs hair-like extensions used for
  absorption

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Roots
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Structures Stem

• Stem
• Function supports, transports and stores food
• Structures
• Vascular Bundle contains xylem phloem tissues
• Pith center most part of the stem
• dicots have a spongy cellular tissue
• Corex surrounds the vascular bundle (only in
  dicots)

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Stem
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Structures Leaves

• Leaves
• Function Primary site of Photosynthesis
• Chloroplasts are found here

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Leaves

• Structures
• Cuticle waxy outer layer of the leaf
• Palisade Layer tightly packed layer of
  chloroplast
• Most of the photosynthesis occurs here

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Leaves

• Structures
• Spongy Layer loosely packed layer of
  chloroplast
• permits air, containing carbon dioxide for
  photosynthesis, to move inside the leaf
• Veins contain xylem and phloem tissue

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Leaves

• Structures
• Stomata found mainly on the lower epidermis
• Regulate gas exchange
• Guard Cells regulate the opening and closing of
  the stomata

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Leaves
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Structures Flowers

• Flowers
• Function reproductive part of the plant

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Flowers

• Structures
• Petals brightly colored part of the flower used
  to attract insects
• Sepals used for protection

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Flowers

• Structures
• Stamen male reproductive part of the flower
• Consist of the anther and filament
• Anther produces the pollen
• Filament holds the anther upright
• Pollen contains the sperm cells of the plant

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Flowers

• Structures
• Pistil female reproductive part of the flower
• Consist of the ovule, stigma, and style
• Ovule eggs
• Ovary contains the eggs (ovules)
• Stigma sticky hairs that receive the pollen
• Style tube connecting the stigma to the ovary

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Flowers
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The Reproductive Process

• Pollination must occur
• Pollen moves from the anther to the stigma by
  wind, water, insects, birds, and animals
• Cross Pollination pollen is transferred from
  the anther of a flower to the stigma of another
  flower
• Self Pollination pollen is transferred from the
  anther of a flower to the stigma of the same
  flower

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The Reproductive Process

• The pollen then grows a pollen tube, which
  travels down the style to the ovary
• Two (2) sperm cells move down the pollen tube

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The Reproductive Process

• One (1) sperm cell joins with one egg to form a
  zygote
• This process is called fertilization
• The second sperm cell joins with two (2) polar
  nuclei, found in the ovary to form an endosperm
• The endosperm becomes food for the developing
  seeds

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The Reproductive Process

• The mature ovary becomes fruit that can be eaten
  or the fruit falls to the ground, expelling the
  seeds
• The new seed may grow into a new plant

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Plants Structure and Function