Unit C: Section 1.0 Flashcards
Can natural things be harmful to living things?
Yes many things like carbon dioxide are harmful but natural
What are elements?
Pure substances that cannot be broken down into anything further
What is the nitrogen cycle?
The way nitrogen moves through the environment and changes
When can plants use nitrogen?
Only when it is paired with other elements such as hydrogen and oxygen
In what compound is nitrogen naturally found in?
Nā
What is nitrogen fixation?
The process of changing free nitrogen so that nitrogen atoms can combine with other elements to form compounds that organisms can use
What does most of the nitrogen fixation?
Certain types of bacteria in soil located in root nodules
In what kind of plants are root nodules found in?
Beans, clover, and alfalfa
What do root nodules do?
They separate the nitrogen gas so it is able to pair with other elements such as hydrogen and oxygen for plants
What are the steps in the nitrogen cycle?
- Nitrogen fixation occurs
- Animals then eat the plants
- Their bodies use the nitrogen to make more complex substances
- Decomposers break down large nitrogen containg molecules in dead organisms and aniimal waste into simpler nitrogen compounds in the soil.
- Eventually some are broken down further by ground bacteria
- Then nitrogen is released back into the air as free nitrogen
What does the concentration of usable nitrogen in the natural environment depend on?
The root nodules, and carrying undissolved nitrogen deep in the soil
If soil lacks nitrogen what do farmers plant?
Nitrogen fixing plants
What is pollution?
Any change in the environment that produces a condition that is harmful to living things
What are some ways humans change the chemical balances in our environment?
Growing crops, solid waste, treating waste water, manufacturing products, and driving vehicles
What is a fertilizer?
A substance that enriches soil so plants will grow
What do the 3 numbers on fertilizer mean?
Nitrogen
Phosphorus
Potassium
What does the 4th number on a fertilizer mean?
it has sulfur added to it
What are pesticides?
Chemicals used to control pests
What is a pest?
An organism that harms people, plants, or structures
What do herbicides kill?
Weeds
What do insecticides kill?
Insects
What do fungicides kill?
Fungi
What is not good about pesticides?
Some are not selective so they end up killing good organsims
What is solid waste?
Garbage that is collected from households, industrial plants, commercial buildings and etc.
What are incinerators?
Places that burn solid waste
What are sanitary landfills?
Places that are built to prevent fluids from going into the soil
What is sewage?
Wastewater containing dissolved and undissolved materials fro your kitchen bathroom, and laundry
Where does sewage go?
Through pipes into a septic tank
What is a septic tank?
An underground container where bacteria breaks down the organic materials before they are moved out to the soil
What is a sewage treatment plant?
Treats waste from homes, businesses, and industries. Might also treat water from street drains
What is effluent?
Treated wastewater that is released into rivers or lakes
What are storm sewers?
Where rain water goes
What are fossil fuels?
Coal, oil, and natural gas. They are formed from dead plants and animals
Why are fossil fuels called hydrocarbons?
Because they are mainly made from hydrogen and carbon