1. Biogeochemical Cycles
Day 23
Biogeochemical Cycles

2. THE GENERAL NUTRIENT CYCLE
Source: Coronel et. al. (2006). Exploring and Protecting Our World 6.
Quezon City: Vibal Publishing House, Inc. p. 107.

3. What do plants need to make food?
Where do plants get water? carbon dioxide? sunlight?
Water and carbon dioxide are examples of inorganic nutrients.

4. NUTRIENTS THAT PRODUCERS NEED
Plants make food using nutrients from soil, water, and air. Examples of these nutrients are minerals such as phosphorus and nitrogen (in the form of nitrates, a nitrogen compound) that come from soil, and carbon dioxide which comes from air. These nutrients are called inorganic nutrients because they come from nonliving things.

5. Some of the foods produced by plants are carbohydrates which contain carbon, hydrogen and oxygen; and proteins which contain nitrogen, carbon, hydrogen and oxygen. Carbohydrates and proteins are examples of organic compounds. Organic compounds come from living things.
Nutrients alternate between their inorganic form in the environment and their organic form in living things.

6. What do decomposers do to the remains of dead organisms?

7. Decomposers
Eventually, people and animals die. Bacteria, fungi and worms feed on the remains of dead organisms. As they do so, they break down the organic compounds and release the nutrients back to the air and soil.

8. THE CARBON DIOXIDE-OXYGEN CYCLE

9. Through the process called photosynthesis, plants make food by absorbing carbon dioxide (CO2) in air. Oxygen gas (O2) is released in air as a by-product of photosynthesis.
CHEMICAL REACTION:
6CO2 + 12H2O glucose + 6O2 + 6H2O
Sunlight energy

10. glucose + 6O2 + 6H2O 6 CO2 + 12H2O + energy
Through the process called cellular respiration, animals (and also plants) use O2 and produce energy and release CO2 in air.
CHEMICAL REACTION:
glucose + 6O2 + 6H2O CO2 + 12H2O + energy

11. THE CARBON CYCLE
Source:

13. Carbon moves from the air to plants. during photosynthesis
“Carbon is part of the ocean, air, rocks, soil and all living things. Carbon doesn’t stay in one place. It is always on the move!” Can you explain again how each movement of carbon happens?
Carbon moves from the air to plants.
during photosynthesis
Carbon moves from plants to animals.
when the animals eat the plants
Carbon moves from plants and animals to the ground.
when plants and animals die and lay to the ground

14. Carbon moves from living things to the atmosphere.
when the living things exhale/respire
Carbon moves from fossil fuels to the atmosphere.
when fossil fuels are burned
Carbon moves from the atmosphere to the oceans.
when the carbon soaks into the oceans

15. Watch these videos of carbon cycle.

16. THE NITROGEN CYCLE

17. Source: http://www.physicalgeography.net/fundamentals/9s.html

18. What are the four basic processes involved in the Nitrogen Cycle?
1. Nitrogen fixation – nitrogen gas in the air is fixed by the lightning or nitrogen-fixing bacteria in plants into ammonia then organic nitrogen. 2. Mineralization - the organic nitrogen turns into ammonia then ammonium. 3. Nitrification – when nitrifying bacteria or nitrifiers oxidize ammonium into nitrites then into nitrates. 4. Denitrification – when denitrifying bacteria break down nitrates into nitrites then into nitrogen gas back into the atmosphere.

19. Watch these videos of nitrogen cycle.0
nd=0

20. CINCH Lesson page
Read ‘Cycles of Matter’ lesson page about the Biogeochemical Cycles Refer to CINCH Life Science 6-8 lesson page

21. ASSIGNMENT:
Depending on your class number, research of a credible news (online) article in or about the Philippines that tackles on how certain events and activities disturb the interrelationship in an ecosystem/biosphere.
CNs  climate change
CNs  muro-ami fishing
CNs  overpopulation
CNs  illegal logging
CNs  kaingin system
CNs  quarrying
CNs  natural calamities
Read, save that article and take note of the link to your reference.

22. Adapted from the modules prepared by Ms. Tolosa and Ms. Pe Benito
References:
Coronel et. al. (2006). Exploring and Protecting Our World 6.
The Carbon Cycle
Nitrogen Basics – The Nitrogen Cycle
ACKNOWLEDGEMENT
Adapted from the modules prepared by Ms. Tolosa and Ms. Pe Benito