Ms. Aguirre Part A- Chapter 3
Common Parts There are more than half a million types of vascular plants on Earth.
No matter how different they are, vascular plants have three parts in common
These three parts make it possible for vascular plants to live an grow almost everywhere.
Vascular plants are found in dry deserts, wet jungles, and the cold Arctic. They are able to live in these environments because their roots, stems, and leaves adapt to these environments.
Roots Spread as far from the trunks as the branches Act as anchors so the tree doesn’t fall over
Root Hairs Take in water and minerals from the soil through root hairs
Different roots adapt to different environments Roots spread far and close to the surface to take in large amounts of the little rain Desert
Forest- deep roots and prop roots Deep roots serve as anchors and prop roots help so they are not being blown in the wind.
Fibrous roots look like tree branches just underneath the surface They are like a tangled mat just underneath the surface of the soil and prevent soil erosion They anchor the plant and the soil
Single thick root that grows straight down. They can reach water deep in the ground Can store food for the plant as well
Plants that grow on big trees In tropical rainforests there are plants that grow on branches and take water directly from the moist air.
Storage Some plants store extra food and water to help them survive changes in their environment. Some store so much extra food that people grow them for their own food.
Stems Hold up the plant Carry food and water to other parts of the plant Grow up to reach the sunlight
Strawberry Plants and Spider Plants Stems grow sideways for new plants to grow.
Stem of a barrel cactus stores water so when rain is scarce, it uses water from its stem.
Daisies and dandelions have stems with water inside that keep the stems firm.
When you cut they begin to droop They have no more water inside the stem to hold it up.
Bushes and stems usually have stiff, woody stems for the extra support they need.
Woody plants don’t die after one growing season but continue to grow year after year. Redwoods grow for hundreds of years.
Xylem move water and minerals upward from roots to the leaves. The strings you bite when eating celery are xylem tubes
These are the tubes that carry food. They move the food made in the leaves to other parts of the plants
In flexible stems, xylem and phloem are in bundles scattered all through the stem. In woody stems, the xylem and phlem are arranged in rings (xylem is toward the middle and phloem is around the outside. With each growing season the stem of a woody plant gets bigger and bigger. More xylem and phloem forms each year, so the thickness of a tree trunk is xylem. The old xylem is the heartwood of a tree. The heartwood is used to build houses.
Leaves Food factories Small, large, but usually flat Use water from the soil, carbon dioxide from the air, and energy from the sun to make food Also produces oxygen and release into the air
A pigment, or coloring matter, called chlorophyll helps plants us light energy to produce sugars
In the fall, as the days get shorter, most leaves stop making chlorophyll
Inside the leaf are layers of cells containing microscopic chloroplasts which are full of chlorophyll
The food making process takes place in these chloroplasts which are full of chlorophyll
Veins bring water and minerals to the chloroplasts and take sugars from them
The stomata open wide during the day when the plant is making food and close at night to conserve water
The waxy outer layer on top fo most leaves helps to conserve water during the heat of the day
The Venus Fly Trap- They grow where soil may not have enough nutrients the plant needs to make food.
It snaps shut when an insect lands on it and take the nutrients from the insect it needs.
Natural Cycles Stores lots of oxygen, nitrogen, and carbon dioxide Iron, copper, magnesium, and calcium are stored in rocks
Running water slowly wears away rocks, releasing stored material. They dissolve in rivers, lakes, and become part of the soil Animals drink the water and get nutrients it needs. They get most of their nutrients from food, and then their waste becomes part of the environment
Not only does their waste become part of the environment, but so does their bodies. This is all an example of how many plants and animals use these materials
The Nitrogen Cycle All living organisms need nitrogen Plants use nitrogen to make proteins
Animals get the nitrogen they need to make proteins when they eat plants or other animals
Earth’s atmosphere is made up of 78 percent nitrogen But most organisms cannot use nitrogen in this way
In the nitrogen cycle, nitrogen gas is fixed, or changed into forms that plants can use These forms are nitrates and ammonia
Animals get nitrogen by eating the plants An animals waste product put nitrogen back into the soil. Solid waste= nitrates Urine= ammonia
This process stayed in balance for millions of years with animal and plant processes Humans began to use machines during the Industrial Revolution, so factories needed huge amounts of fuels.