Download Objective: 1 - davis.k12.ut.us

Objective: 1. Students will explain the cycles of nature.
2. Students will name and identify renewable resources.
3. Students will name and identify nonrenewable resources.
VII. Cycles of Nature
a. Water cycle: is the movement of water from the surface of Earth to the air
(atmosphere) and back to the surface in a continuous cycle.
1. Evaporation: when the surface water becomes a gas (water vapor).
2. Condensation: when the water vapor in air becomes cool enough to condense
into clouds (must have cloud forming nuclei).
3. Precipitation: when water vapor that has condensed is too heavy to remain in
the clouds and falls to the ground as hail, sleet, snow, graupel, or rain.
b. Carbon cycle: is made of 2 parts, the gaseous carbon of the atmosphere (CO, CO2)
and the solid carbon found in the Earth or organisms (sugars, graphite, diamonds,
carbon in ores/rocks). Most carbon in the cycle is in solid form but organisms use
the gaseous carbon during photosynthesis to make the carbon organisms need.
During photosynthesis, gaseous carbon gets changed to solid carbon as sugars.
Plants use the sugar they make for energy while other organisms eat plants directly
to use the sugar or other organisms eat something that has already consumed the
plant to use the sugar. The organisms may then create waste or die which then
leads decomposers to breakdown the waste or carcass releasing CO 2 gas back into
the atmosphere. So the cycle starts again.
c. Nitrogen cycle: the atmosphere is made of 78% nitrogen gas (N2); however, almost
all organisms on the planet do not have a way to use it directly from the air. So,
we need intervention which comes in the form of nitrogen-fixing bacteria. The
bacteria break down the nitrogen, from air, into a form that plants use during
photosynthesis. Other organisms then consume the plants or consume someone
who did, thus allowing all organisms to benefit.
d. Phosphate cycle: The element phosphorus exists in rocks and soils as the ion
phosphate (PO4)3. Phosphate rock is mined and used in various fertilizers.
Phosphate ions dissolve in water and are taken up by plants and combined into
organic compounds. These organic compounds are passed through the food chain.
When organic phosphate is oxidized and used for energy in the organism the
phosphate is released in urine or other waste products and absorbed by plants from
the soil or water. Phosphates in soil, rocks and water are referred to as inorganic
phosphate.
e. Natural resources are any resources supplied by the Earth (that humans extract
and use) and the Sun.
1. Renewable resources are natural resources that seem to have a
continuous supply or can be renewed and formed quickly. Examples of
renewable resources include trees, water, the sun, and anything that can
cycle through the Earth.
2. Nonrenewable resources are natural resources that take a very long
time to form or are used faster than they can replenish themselves.
Examples of nonrenewable resources include fossil fuels (oil, natural
gas or), precious metals (gold, silver) or precious gems (diamonds,
rubies).