Warm Up

Which is the bigger problem for humans: too much water (flooding) or too little water (drought)? Defend your stance.

Cycling of Matter

• Students will learn how matter moves through an ecosystem.
• Students will learn the difference between a food chain and a food web.
• Students will diagram the ways matter cycles through an ecosystem.

Closed Loops Cycle

• All matter on Earth exists in a fixed amount.
• Matter cycles through the environment, from one organism to another and back to the environment.
• Matter is transformed, but never created or destroyed.
• Two major cycles: the water cycle and the nutrient cycles (carbon, nitrogen, phosphorus).

Importance of Cycling of Matter

• Ensures the availability of essential elements for life, like carbon and nitrogen.
• Supports the health and balance of ecosystems.
• Prevents the buildup of waste products and harmful substances.
• Enables the continuous flow of energy and nutrients.

The Water Cycle

• Water evaporates from bodies of water, plants, and soil.
• Water vapor rises, cools, and condenses into clouds.
• Precipitation returns water to Earth's surface.
• Water collects in oceans, rivers, lakes, and groundwater.
• The sun's energy drives the water cycle.

Phases of H2O

• Evaporation: Liquid to Gas
• Condensation: Gas to Liquid
• Freezing: Liquid to Solid
• Melting: Solid to Liquid
• Sublimation: Solid to Gas
• Deposition: Gas to Solid

Types of Precipitation

• Rain: Liquid water falling from clouds.
• Snow: Frozen water falling from clouds.
• Sleet: Rain that freezes into ice pellets before reaching the ground.
• Hail: Balls or irregular lumps of ice falling from clouds.

pH

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Acid <7

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Neutral = 7

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Base >7

Warm Up

IIs carbon Dioxide good or bad? why?

The Carbon Cycle

• Carbon is released into the atmosphere through natural processes (volcanic eruptions, decomposition) and human activities (burning fossil fuels).
• Plants absorb carbon dioxide during photosynthesis to build carbohydrates.
• Animals consume plants, incorporating carbon into their bodies.
• Carbon is returned to the atmosphere through respiration and decomposition.
• The ocean absorbs and stores carbon dioxide, helping regulate the climate.

Photosynthesis: An Overview

Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar.

This process is essential for life on Earth as it provides the oxygen that we breathe and the food that we eat.

Photosynthesis takes place in the chloroplasts of plant cells, which contain chlorophyll, a green pigment that absorbs sunlight.

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Cellular Respiration

• Cellular respiration converts glucose and oxygen into ATP, releasing carbon dioxide and water as byproducts.
• ATP provides energy for cellular processes.
• Occurs in the mitochondria of cells.
• Cellular respiration is the opposite of photosynthesis.

Carbon (purple) and Oxygen (orange) Cycle

Warm Up

Farmers have increased the amount of fertilizer they use on crops.Do you think it’s better to rely on natural ecosystems (like bacteria in soil) or human technology (like fertilizers) to keep our food supply stable? Provide 2 sentences explaining why.

The Nitrogen Cycle

• Nitrogen gas makes up 78% of the atmosphere.
• Plants can't use nitrogen gas directly.
• Bacteria convert nitrogen gas into usable forms.
• Plants absorb nitrogen compounds through their roots.
• Animals obtain nitrogen by consuming plants or other animals.
• Decomposers break down waste, releasing nitrogen back into the soil.

Nitrogen Fixation

• Nitrogen Fixation: Converting atmospheric nitrogen (N2) into ammonia (NH3).
• Biological nitrogen fixation: Done by prokaryotes, like rhizobia bacteria.
• Industrial nitrogen fixation: Artificial production of ammonia, requires high temperature and pressure.
• Importance: Essential for plant growth and ecosystem health.

Nitrification

• Nitrification is the process of converting ammonia (NH3) to nitrate (NO3-).
• Nitrification is an important step in the nitrogen cycle.
• Nitrification is performed by two groups of bacteria: Nitrosomonas and Nitrobacter.
• Nitrosomonas convert ammonia (NH3) to nitrite (NO2-).
• Nitrobacter convert nitrite (NO2-) to nitrate (NO3-).

Denitrification

Eventually, Bacteria Conver those Nitrates (NO3) into Atmospheric Nitrogen (N2)

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This process prevents a build of o f nitrogen in the soil, which would kill plants

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Also replenishes atmospheric nitrogen supply

Warm Up

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What are ways the humans disrupt the

• Water Cycle
• Carbon Cycle
• Nitrogen Cycle

The Phosphorus Cycle

• Phosphorus is an essential nutrient for plant growth.
• Found in rocks, soil, and water.
• Weathering releases phosphorus from rocks.
• Plants absorb phosphorus from soil.
• Animals obtain phosphorus by consuming plants or other animals.
• Decomposers break down waste, returning phosphorus to the soil.
• Runoff can carry phosphorus into water bodies, causing algae blooms.

The Silicon Cycle

• The process by which silicon moves from the Earth’s crust into the oceans and back
• Weathering: Rocks and minerals break down over time due to forces such as wind and water.
• Transportation: Silicon is transported through rivers and groundwater.
• Absorption: Phytoplankton absorb and incorporate silicon into their skeletons
• Sinking, dissolution, and burial: When marine organisms die, their skeletons sink to the bottom of the ocean and either dissolve or are buried in sediment.

Human Impact on Cycles

• Human activities significantly influence the cycles of matter.
• Burning fossil fuels releases carbon dioxide, impacting the carbon cycle.
• Agriculture and deforestation affect both the carbon and nitrogen cycles.
• Pollution and runoff disrupt the water cycle and phosphorus cycle.
• Sustainable practices can mitigate negative impacts on cycles of matter.

Discussion Questions

How do human activities impact the carbon cycle?

Why is nitrification important to the nitrogen cycle?

What are the effects of human activities on the phosphorus cycle?

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