How are plants classified?

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How are plants classified?

• Lesson 3

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Vocabulary

• Gymnosperm a seed plant that does not produce a
  flower. They include pines, firs, and other
  cone-bearing trees.
• Angiosperm a seed plant that produces flowers.
  All angiosperms have seeds that are covered by
  some kind of fruit.
• Xylem a series of tubes that move water and
  minerals up the stem. (From the plant roots to
  the leaves)

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Gymnosperm, Angiosperm, Xylem
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Vocabulary

• Phloem moves sugars that are made in the
  plants leaves to other parts of the plant.
  Phloem tissue is a two-way transport route. It
  flows both up and down in a plant.
• Cambium xylem and phloem cells are produced in
  the cambium, then move inward.
• Photosynthesis the process of making food.
  Leaves need three raw materials sunlight, water,
  and carbon dioxide from air.

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Cambium, Phloem
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Photosynthesis
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Vocabulary

• Transpiration the loss of water through a
  plants leaves. Picture on page 58.
• Cellular respiration energy is released when
  the cells of organisms use oxygen to break down
  the sugars stored as starch.

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Transpiration, Cellular respiration
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How are plants classified?

• Nonvascular plants are small and survive without
  a transport system. (Moss)
• Vascular plants do not have size limitations.
  Trees can grow to heights of more than 200 feet.
  
• Vascular plants are divided into seed plants and
  seedless plants.

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Nonvascular, Vascular
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How are plants classified?

• Two main types of seed plants gymnosperm (does
  not produce a flower), and angiosperm (does
  produce a flower).

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What are roots?

• A root is part of the plant.
• Root hair is a threadlike projection from a plant
  root. Root hair absorbs moisture like a sponge.
  
• Root cap covers the tip of the root. It protects
  the root tip while it pushes into the ground.
• Epidermis is the skin of the root. Just like our
  epidermis is our skin.

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What are roots?

• Cortex layer is located just under the epidermis.
  The cortex stores food and nutrients.
• The vascular system of the root is located in the
  center of the root. Just like our vascular
  system is in the center of our body.
• Aerial roots are roots that never touch the
  ground. Orchids have aerial roots.

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What are roots?

• Fibrous roots are thin, branching roots. They do
  not grow deep, but they often cover a very wide
  area. (Marigold plants)
• Taproots have a single, main stalk-like root that
  plunge into the ground. (Poplar Tree)
• Prop roots usually grow at the bottom of a
  plants stem. They prop up and support the plant
  so it cannot be knocked over. (Corn plants and
  mangrove trees)

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Fibrous roots, Taproots
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Prop roots
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What are stems?

• The plants stem has two functions. First, is a
  support structure. The stem of a tree must
  support the weight of the entire tree. Stems
  must be sturdy enough to support leaves, flowers,
  and branches.
• Stems come in two basic forms-soft stems and
  woody stems.
• Soft stems, green, and can bend.
• Woody stems are often covered with bark and do
  not contain chlorophyll.

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Plant and Stem
Allows sugar from the leaves of the tree to flow
to the rest of the tree.
Allows water and nutrients from the ground to
flow to the rest of the tree.
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What are leaves?

• Many leaves are flat and broad, which allows the
  leaf to collect the most sunlight possible.
• The top of the leaf is covered with a waxy
  cuticle, or waterproof layer that prevents
  moisture from evaporating.
• Leaves use stomata, a single pore which opens and
  closes to regulate the amount of water and air
  loss in the plant.

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Plant leaf
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What are leaves?

• As water evaporates from the leaves, more water
  is carried from the bottom of the plant to the
  top.
• Photosynthesis, the production of sugar and
  oxygen while absorbing carbon dioxide and water.

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How are photosynthesis and respiration related?

• Cellular respiration the process of using
  oxygen to break down the sugars stored as starch
  in the process.
• Cellular respiration occurs in the mitochondria
  of the cells.

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Cellular respiration in plants