Back to: ZOOLOGY 100 Level
I’m so happy you’re here and ready to learn something new today! You are truly on a roll, and I’m proud of how far you’ve come. Today, we’re going to talk about nutrient cycles, specifically the carbon, nitrogen, and water cycles. Don’t worry — these cycles are like nature’s way of recycling, and I’ll break them down for you in a way that’s easy to understand. Let’s dive in!
Nutrient cycles (carbon, nitrogen, water cycles)
What are Nutrient Cycles?
Nutrient cycles are the processes through which essential nutrients like carbon, nitrogen, and water move through the environment, from living organisms to the soil, and back again.
These cycles are important because they keep the environment healthy by ensuring that living things always have access to the nutrients they need.
The Carbon Cycle
The carbon cycle shows how carbon moves through the environment.
- Plants take in carbon dioxide (CO₂) from the air during photosynthesis and turn it into food (glucose).
- Animals eat the plants and get the carbon they need to grow.
- When animals and plants die, decomposers (like bacteria and fungi) break them down, releasing carbon back into the soil and air.
- Carbon is also released when animals breathe out and when fossil fuels like coal and oil are burned.
Simple Example:
The air has carbon dioxide, which plants use to make food. Animals eat the plants, and when they die, their carbon returns to the environment.
The Nitrogen Cycle
The nitrogen cycle shows how nitrogen, an essential nutrient for plants and animals, moves through the ecosystem.
- Nitrogen-fixing bacteria in the soil take nitrogen from the air and turn it into a form that plants can use.
- Plants absorb this nitrogen and pass it on when animals eat the plants.
- When animals and plants die, decomposers break them down and release nitrogen back into the soil.
- Some nitrogen also returns to the air through denitrifying bacteria.
Simple Example:
You know how we need protein to grow strong? Well, plants use nitrogen to make proteins, and animals eat plants for those proteins. When animals and plants die, nitrogen returns to the soil to help new plants grow.
The Water Cycle
The water cycle shows how water moves around the Earth, from the air to the ground, and back again.
- Evaporation: Water from oceans, rivers, and lakes turns into vapour and rises into the air.
- Condensation: The water vapour cools down and forms clouds.
- Precipitation: Water falls back to Earth as rain, snow, or hail.
- Infiltration: Some water soaks into the ground, replenishing the water in the soil.
- Transpiration: Plants take up water from the soil and release it into the air through their leaves.
Simple Example:
The water we see in rivers, lakes, and oceans moves in a cycle. It evaporates into the sky, forms clouds, then falls as rain to water the earth, and the cycle continues!
Summary
- Nutrient cycles are important for recycling essential nutrients like carbon, nitrogen, and water in nature.
- The carbon cycle shows how carbon moves from the air to plants and animals and back to the environment.
- The nitrogen cycle involves the movement of nitrogen from the air to the soil and to plants and animals.
- The water cycle shows how water moves through the environment in a continuous loop.
Evaluation
- What are nutrient cycles?
- Explain the carbon cycle in simple terms.
- Why is nitrogen important for plants and animals?
- Describe the water cycle and its stages.
- How do nutrient cycles help maintain a healthy environment?
Every new lesson you learn adds more strength to your foundation. Keep going, because you’re on the right path to achieving amazing things. Afrilearn is so proud of you, and we’re here cheering you on every step of the way!