Huwebes, Setyembre 26, 2013

SCIENCE AND HEALTH 6 (Mrs. Jonabel Quintana)



SCIENCE AND HEALTH 6
Course Outline (2nd Grading)
            1. Ecology and Energy Transfer
                        Ecosystem
                        Food Chain, Food Web, Energy Pyramid
                        Balance of Nature
                        Relationships that Exist in Ecosystem
            2. Nutrient Cycles in Ecosystem
                        Carbon dioxide – Oxygen Cycle   
                        Carbon Cycle
                        Nitrogen Cycle

Lesson 1
Relationships That Exist in Ecosystem
1. Mutualism – In this kind of relationship, both organisms benefit from each other.
            Ex. flagellates and termites, plants and animals, flower and bee
2. Commensalism – In this kind of relationship, one organism benefits from the relationship while the second organism is unaffected by it.
            Ex. sea anemone and clown fish, coral and fish, orchid and tree
3. Amensalism – In this kind of relationship, the growth of one organism is inhibited while the other is unaffected.
            Ex. shading effect of the tree on small plants
4. Parasitism – This is a relationship between two organisms wherein one organism (the parasite) benefits for growth and reproduction while the other organism (the host) is harmed.
            Ex. dog and ticks, child and intestinal worm, plants and aphids
5. Predation - In this type of relationship, an organism (prey) is hunted and eaten by a stronger organism (the predator)
            Ex. snake and frog, tiger and squirrel, eagle and rabbit
6. Competition – This relationship exists when an ecosystem has reached its carrying capacity. Thus, the organisms compete for food, space, and resources.
            Ex. pechay plants and weeds, fish in an aquarium

Lesson 2
            Nutrient Cycles in Ecosystem

            No material is lost in a balanced or stable ecosystem. This is because materials are continually taken from the nonliving environment and used by living things. Then they are released into the nonliving environment to be used again by living things. The use and reuse of materials in an ecosystem is called recycling. This process ensures that an ecosystem does not run out of materials. Recycling makes an ecosystem self-sustaining.

            Carbon dioxide and Oxygen Cycle

http://www.webquest.hawaii.edu/kahihi/sciencedictionary/images/symbiosis.png
            In the carbon dioxide-oxygen cycle, plants take in carbon dioxide released by humans and animals. They use this in the food-making process called photosynthesis.  In return, plants produce oxygen that humans, animals, and plants use in respiration.

           

Carbon Cycle

http://eo.ucar.edu/kids/green/images/carboncycle_sm.jpg

All living things are made of carbon. Carbon is also a part of the ocean, air, and even rocks. Because the Earth is a dynamic place, carbon does not stay still. It is on the move!
In the atmosphere, carbon is attached to some oxygen in a gas called carbon dioxide.
Plants use carbon dioxide and sunlight to make their own food and grow. The carbon becomes part of the plant. Plants that die and are buried may turn into fossil fuels made of carbon like coal and oil over millions of years. When humans burn fossil fuels, most of the carbon quickly enters the atmosphere as carbon dioxide.
Carbon dioxide is a greenhouse gas and traps heat in the atmosphere. Without it and other greenhouse gases, Earth would be a frozen world. But humans have burned so much fuel that there is about 30% more carbon dioxide in the air today than there was about 150 years ago, and Earth is becoming a warmer place. In fact, ice cores show us that there is now more carbon dioxide in the atmosphere than there has been in the last 420,000 years.

Nitrogen Cycle

http://www.h2ou.com/h2images/NitrogenCycle-lgr-F.jpg


            Plants absorb nitrogen in the form of nitrates, which are very soluble salts. Nitrates are formed through the processes of nitrogen fixation, nitrification, and decay. Nitrates are absorbed by plants from the soil or water. These nitrates are then incorporated by plants to form proteins and other compounds, which can be spread through the food chain. When animals eat plants, they get the nitrogen in nitrate form. When organisms die, their bodies are decomposed by bacteria and fungi. The decomposition process produces ammonium compounds which dissolve in the soil and water. By the action of denitrifying bacteria, the nitrates in the water and soil are converted into gaseous nitrogen and are released into the atmosphere.




                                                                    

Walang komento:

Mag-post ng isang Komento