Download Plants - Mr. Swords` Classes

21-1 Plants
5/13/13
Photosynthesis
6H2O + 6CO2 ----------> C6H12O6 + 6O2
Six molecules of water plus six molecules of carbon
dioxide produce one molecule of sugar plus six
molecules of oxygen
There are over 350,000 different species of plants. Plus many more that remain undiscovered.
These undiscovered species of plants most likely live in the rain forests and underwater.
All plants have 2 things;
1.
Chloroplasts – green cell parts that contain chlorophyll. Chlorophyll traps light energy. The
light energy + water + carbon dioxide combine to make food (glucose) for the plant. This process
is called photosynthesis. Oxygen is the waste product of that process.
(Don’t copy this, just read it)
Deciduous trees - During winter, there is not enough light or water for photosynthesis. The trees will rest, and live
off the food they stored during the summer. They begin to shut down their food-making factories. The green
chlorophyll disappears from the leaves. As the bright green fades away, we begin to see yellow and orange colors.
Small amounts of these colors have been in the leaves all along. We just can't see them in the summer, because they
are covered up by the green chlorophyll.
The bright reds and purples we see in leaves are made mostly in the fall. In some trees, like maples, glucose is
trapped in the leaves after photosynthesis stops. Sunlight and the cool nights of autumn cause the leaves to turn this
glucose into a red color. The brown color of trees like oaks is made from wastes left in the leaves.
2.
Stiff cell walls that give that plant structure. Cell walls are especially important to plants
that live on land. (except moss, which does not have cell walls)
Plants are grouped (classified) by how they transport nutrients about themselves.
Vascular plants – have “veins.” These veins are tube-like plumbing to distribute nutrients.
Nonvascular plants - plants without veins. These plants absorb nutrients directly into their cells
from their surroundings (every cell for itself).
Example; mosses, liverwort
Liverworts
Non vascular plants need to live close to the ground in order to be near the nutrients, such as
water and minerals. They can’t grow tall because they don’t have veins to deliver food to their
cells.
All plants go through a life cycle of alternating generations;
Seed Bearing Plants
Seed bearing plants reproduce by dropping fertilized (2n) embryos with a food supply to the
ground.
Fruits usually have fertilized seeds (2n) inside and are usually sweet tasting to
encourage animals to eat and disperse them. They come from the blossoms of
flowering plants.
Non-seed bearing plants reproduce by releasing unfertilized spores (n) or male gametophytes
in the hopes that they somehow reach a female gametophyte.
Diploid
haploid
Non-seed plants
gametes
generations
gametophytes
meiosis
sporophytes