Cycles in Nature

Cycles in Nature

Earth Cycles

• Most of the matter on Earth is the same matter that was here when the Earth was formed.

• Instead of leaving it continues to change form as it cycles through one of the many cycles of Earth's system.

What is a cycle?

A cycle is a series of events that are regularly repeated in the same order.

Carbon

• Carbon atoms are the basis for all life on Earth. These atoms are found in all molecules that make up living organisms—carbohydrates, lipids, proteins, and nucleic acids. These molecules are called organic molecules.

• Carbon can connect with several other atoms, including other carbon atoms.

The Carbon Cycle

• Carbon moves back and forth between the nonliving environment and the organic molecules found in organisms. This cycle is called the carbon cycle

• Carbon in the form of carbon dioxide gas is found in the air and dissolved in water. Plants use carbon dioxide from the air or water to make the sugar glucose in the process of photosynthesis

Multiple Choice

Coal and petroleum are examples of

• slow carbon

• quick/fast carbon

The Nitrogen Cycle

• Proteins are the most abundant organic molecules in living things, and they perform many functions. Nitrogen is a key element in proteins. The movement of nitrogen from the atmosphere to living organisms and back to the atmosphere is called the nitrogen cycle. Bacteria are crucial to the success of this cycle

Nitrogen Fixing

• Although nitrogen gas (N2) makes up 78% of the atmosphere, most organisms cannot use the nitrogen from nitrogen gas.

• Some types of bacteria are able to use nitrogen atoms from the atmosphere.

• They live in the soil and on the roots of certain plants like beans, clover and peas.

Multiple Choice

What helps make nitrogen available for other biotic organisms?

• whales

• shrimp

• trees

• bacteria

Carbon and Nitrogen

• For billions of years the matter that makes up living andorganisms has cycled between living and nonliving parts of the ecosystem

• Carbon and nitrogen cycle between abiotic and biotic parts of the Earth.

The Water Cycle

• Water is another important element of our planet.

• Water moves through our bodies and through the hydrosphere all over Earth.

Water

• Water is always flowing from solid to liquid to gas in the hydrosphere.

• Evaporation, condensation, precipitation and collection areas are crucial to Earth's Water Cycle.

Four Water Processes

• Evaporation is when liquid water from lakes and oceans turns into gas and rises in the atmosphere.

• Condensation is when water vapor cools into liquid drops to form clouds.

• Precipitation is when liquid or solid water falls from the atmosphere to the earth. Rain, snow, sleet, or hail are all precipitation.

• Runoff and collection is when water travels down the land into rivers, lakes, and oceans.

Multiple Choice

Why do plants need to obtain carbon atoms?

• Carbon is their food.

• They use carbon to breathe.

• Plants use carbon to build glucose during photosynthesis.

• Plants use carbon to build glucose during photosynthesis.

Multiple Choice

How do humans obtain the nitrogen they use in their bodies?

• by absorbing nitrogen found in the soil

• by breathing the nitrogen present in the atmosphere

• by absorbing ammonia from bacteria growing in the roots of plants

• by consuming plants or other animals

Multiple Choice

What is a key element found in CO2 and glucose?

• ammonia

• carbon

• nitrogen

• legumes