Examining Plant Structures and Functions

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Examining Plant Structures and Functions

• Created By
• Eric Johannesen
• Iowa-Grant High School

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Cellular Structure in Plants

• Cells are the structure that forms the basic
  building blocks of all living things.
• A cell
• Tiny structure that forms the basic building
  blocks of all plants
• All organisms are made up of one or more cells
• Protoplasm in cells carry out life processes

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Cellular Structures of Plants

• Plants are multi-cellular organisms
• This means they have many cells
• Cell specialization is the presence of cells that
  perform unique activities for a plant.
• Flowers, leaves, roots, and stems are made up of
  specialized cells.
• Cells are formed into groups that work together
• Tissue-Formed- by groups of cells that are alike
  in activity and structure.
• Organ-Formed by tissues that work together to
  perform specific functions
• Organ system-Group of organs that works together
  to perform a function

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Cell Structure

• Plant cells have three major parts
• Cell Wall
• Surrounds the cell and controls movement of
  materials into and out of the cell
• Nucleus
• Center of the cell and contains protoplasm,
  chromosomes, and other structure that control
  cell activity
• Cytoplasm
• Thick solution inside the cell wall surrounding
  the nucleus
• Plant Cells have many additional parts
• Chloroplasts, nucleolus, vacuole, mitochondria,
  golgi

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The Plant Cell
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Major Parts of Plants

• Plants are comprised of vegetative and
  reproductive parts
• Vegetative Parts
• Stems
• Leaves
• Roots

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Stems

• Central axis that supports the leaves, connects
  them with the roots, and transports water and
  other material between the leaves and roots.

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Stems

• Rhizomes-Below ground horizontal stems
• Stolons-Above ground horizontal stems
• Tubers-is an enlarged part of a stem that grows
  underground (potatoes and yams)
• Tendrils- Threadlike leafless growth on a stem
  that attaches itself to other stems and objects
  (Grapes, Sweet Peas, Cucumbers)
• Bulbs-Underground food-storage organs (onions,
  daffodils)
• Corms-is a food storage structure at the end of
  the stem. (Gladiolus)
• Cladophyll-Leaf like branch that resembles a leaf

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Stems
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Stems
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Roots

• Two Types
• Fibrous Root System
• Made of many small roots and spread throughout
  the soil.
• Taproot Root System
• Made up of one primary root with a number of
  smaller secondary roots called root hairs.

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Roots
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Leaves

• Large, flat, and green organ attached to the
  stem. Its primary purpose is to produce food
  through photosynthesis.
• Two Major kinds of leaves
• Simple
• Compound

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Simple Leaves
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Compound Leaves
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Leaf Attachment

• Refers to the spacing and arrangement of leaves
  on the stem of the plant
• Alternate-One leaf at each node on a stem
• Opposite-Two leaves are attached at nodes
  opposite of each other
• Whorled-Three or more leaves are at each node.

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Leaf Attachment
Whorled
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Reproductive Parts

• Flower, Seed, and Fruit
• The Flower
• Contains the reproductive organs
• Flowers produce pollen and ovules
• The Seed
• Formed by fertilized ovules and contain new plant
  life
• The Fruit
• Ovaries which develop to protect and nourish the
  developing seed.

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The Flower
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Seeds
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Plant ID by Cotyledons

• A Cotyledon is the fleshy structure within a seed
  that contains food for a developing embryo.
• Monocotyledons
• Produce one seed leaf
• Grasses-Corn, Wheat, Oats, Ryegrass
• Have long narrow leaves with parallel veins
• Dicotyledons
• All other plants other than grass plants are
  Dicots.
• Soybean, lettuce, Green beans, Alfalfa
• Broadleaves with a web-like vein structure.

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Cotyledons
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Nutrient and Water Transport

• Water and nutrients are primarily absorbed by the
  roots and transported throughout the plant by
  various tissues in the root, stems, and leaves.
• Roots have tiny root hairs covered with thin
  membranes that allow water and nutrients to
  enter.
• Process called Osmosis

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Nutrient and Water Transport

• After water and nutrients are absorbed, water is
  passed from cell to cell until it reaches the
  xylem tissue.
• Xylem tissue carries the water and nutrients up
  to the plant from the roots.
• Manufactured food is conducted from the leaves
  through the stems to the roots by Phloem Tissue
• Phloem tissue conducts sugars, proteins,
  hormones, dissolved materials and salts from
  leaves to other parts of the plant

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Plant Functions Reviewed

• Female Flower Function
• Reproduction
• Store food in seeds and fruits
• Stem Functions
• Conduct water
• Conduct manufactured food
• Produces leaves and displays them to the sun
• Supports the leaves
• Stores food reserves

• Male Flower Function
• Pollination
• Leaf Functions
• Photosynthesis
• Transpiration
• Food Storage
• Root Functions
• Absorb water and nutrients
• Anchor the plant
• Store food reserves