Nitrogen Cycle

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Questions and Answers

What is the primary function of insecticides?

To enrich the soil

To kill fungi

To kill insects (correct)

To treat wastewater

Which nutrients are commonly found in fertilizers?

Calcium, Iron, Magnesium

Zinc, Manganese, Copper

Sodium, Chlorine, Bromine

Nitrogen, Potassium, Phosphorus (correct)

How do sanitary landfills prevent waste from contaminating groundwater?

By regularly treating the waste onsite

By using only biodegradable materials

By allowing waste to naturally decompose

Through plastic liners and clay barriers (correct)

What is considered sewage primarily composed of?

Undissolved materials from human use Signup and view all the answers

What is indicated by the term 'sour gas'?

Natural gas containing hydrogen sulfide Signup and view all the answers

What is the primary purpose of nitrogen fixation in the nitrogen cycle?

To make nitrogen usable for plants Signup and view all the answers

Which of the following is NOT a way that nitrogen enters the soil?

By absorption through animal skin Signup and view all the answers

Which of the following best defines pollution?

A change in the environment that is harmful to living things Signup and view all the answers

What role do bacteria in root nodules play in the nitrogen cycle?

They fix atmospheric nitrogen into usable compounds Signup and view all the answers

Which of the following practices is specifically aimed at reducing weeds in agriculture?

Pesticide application Signup and view all the answers

What is the first step in the nitrogen cycle as described?

Lightning converts free nitrogen in the air Signup and view all the answers

How do human activities contribute to changes in chemical levels in the environment?

They introduce pollutants that disrupt natural cycles Signup and view all the answers

Which of the following statements about the nitrogen cycle is incorrect?

Lightning plays no role in the nitrogen cycle. Signup and view all the answers

What occurs in Step One of the nitrogen cycle?

Free nitrogen in the air is converted by lightning. Signup and view all the answers

Which of the following steps involves bacteria converting nitrogen into usable compounds?

Step Three Signup and view all the answers

What happens to the nitrogen that is released back into the air during the nitrogen cycle?

It returns to the atmosphere as free nitrogen. Signup and view all the answers

During which step do plants take up useful nitrogen?

Step Four Signup and view all the answers

What role do animal and plant waste play in the nitrogen cycle?

They break down and release nitrogen compounds into the soil. Signup and view all the answers

Study Notes

Chemicals in the Environment

Chemicals are the building blocks of everything
This unit focuses on harmful chemicals in the environment

Harmful Chemicals

Living things need chemicals to survive
Some chemicals can be harmful to the environment and living things

The Nitrogen Cycle

Nitrogen is essential for living organisms, mainly plants
Plants can't use free-floating nitrogen
Nitrogen needs to be combined with other elements for use by plants
This process is called nitrogen fixation
Nitrogen fixation is often done by bacteria in soil

Nitrogen Cycle in Steps

Step One: Free Nitrogen in the air is converted by lightning
Step Two: Animal/Plant waste are broken down and Nitrogen compounds are released into the soil
Step Three: Bacteria in root nodules convert Nitrogen into useable compounds
Step Four: Plants uptake useful Nitrogen
Step Five: Bacteria will release some free nitrogen back into the air

Processes Affecting Environmental Chemicals

The nitrogen cycle is a natural process that changes chemical levels over time
Humans can also change chemical levels in unnatural ways

Pollution

Pollution is any change in the environment that is harmful to living things
It's not just caused by human activities

Agricultural Practices and Pollution

Pesticides (herbicides, insecticides, fungicides) kill weeds, insects, and fungi
Fertilizers improve soil nutrients to promote crop growth; They usually contain nitrogen, potassium, and phosphorus.
Excess fertilizer can cause harm
Fertilizer labels contain information regarding the percentage of nitrogen, phosphorus, and potassium

Solid Wastes

Solid waste, like garbage, is disposed of in landfills
Sanitary landfills are constructed with plastic liners and clay on top of the waste.
This prevents waste from leaking into the groundwater and soil (leachate)

Waste Water

Wastewater from human use is called sewage
Sewage treatment plants treat sewage from homes and industry
Treated wastewater is sent to rivers and lakes

Fuel Combustion

Fossil fuels (coal, oil, and natural gas) are formed from plants and animals that died millions of years ago
Burning fossil fuels releases carbon dioxide, water vapor, and pollutants (sulfur dioxide, nitrogen oxides, and lead) into the air

Industrial Processes

Industrial processes release chemicals into the air
Natural gas processing can produce "sour gas" (containing hydrogen sulfide) or "sweet gas" (without hydrogen sulfide)

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Description

This quiz explores the role of chemicals in the environment, particularly harmful chemicals and their impacts on living organisms. It also covers the nitrogen cycle, detailing the processes involved in nitrogen fixation and its importance for plants. Test your understanding of these essential concepts!