Flow of Energy & Cycling of Matter

Review7th Grade Science

To compost, or not to compost??• Compost CAN include: – Leaves– Left-over veggies– Left-over fruit– Egg shells

• You WOULDN’T PUT THIS IN YOUR COMPOST BIN:– Charcoal ash– Left-over chicken– A soda can– Plastic candy wrappers

Compost can do WHAT????

• Compost can: – Add nutrients to the soil– Decrease waste in landfills – Add organic matter back to soil

• In a compost bin, you see the process of DECOMPOSITION. During this process, FUNGI and BACTERIA obtain energy by breaking down the WASTE and REMAINS of other living organisms.

Let’s see about that NITROGEN

• Nitrogen makes up 78% of the Earth’s atmosphere.

• Before nitrogen can become useful, it most go through the NITROGEN CYCLE.

• Nitrogen compounds are turned back into atmospheric nitrogen through denitrification.

Remember this!!!!• Energy cannot be CREATED or DESTROYED.

• BIOMASS is matter formed using BOTH PLANTS and ANIMALS that contain stored energy.

• Plants get their CHEMICAL energy by transforming RADIANT energy from the sun.

THE WONDERFUL WATER CYCLE!!

• During TRANSPIRATION, water vapor goes back into the air from a plant’s leaves. This is another example of how water is EVAPORATED.

• When liquid water heats up from the sun’s energy and changes into invisible water, this is called EVAPORATION.

THE WONDERFUL WATER CYCLE!!

• When water falls back to Earth it is called PRECIPITATION. Examples: – Rain– Sleet– Snow– Hail

• During CONDENSATION clouds cool and water vapor changes back into LIQUID WATER.

Everybody loves ECOSYSTEMS

• In an ecosystem, an organism lives in their specific HABITAT. Within this, the organism has a its job or NICHE.

• An organism that makes its own food is a PRODUCER or AUTOTROPH. Examples: – Trees– Flowers– Grasses

WHAT eats WHATWhat Food Example

Carnivores Other animals Lion

Herbivores Plants Deer

Omnivores Other animals and plants

People

Scavengers Bodies of dead animals

Vultures

Did you know????• Organisms that go through the process of

photosynthesis include PLANTS, certain microorganisms, and ALGAE.

• The first organism in a food chain/web/energy pyramid is always a PRODUCER. This has the MOST energy.

• Many overlapping food chains are a FOOD WEB.

Vocab, Vocab, VocabContinental drift Slow movement of a continent

Biogeography Study of where organisms live

Climate Typical weather pattern in an area over a long period of time

Biome Group of ecosystems with similar climates and organisms

Tundra Biome that is extremely cold and dry

Biotic factor All of the living or once-living factors in an ecosystem

Abiotic factor All of the non-living factors within an ecosystem

Neritic zone Biome found below the low-tide line and above the continental shelf

You will need to know…• Within a food web, the amount of energy

transferred to the next level is 10%. When energy is transferred , the arrow points TOWARDS the direction that the ENERGY will go.

• CONSUMERS are called HETEROTROPHS, meaning they rely on other organisms for food.

Dispersal = Travel—plane, train or automobile?

• Examples of dispersal include:– An insect being carried down a river on a floating leaf– A dog brining home sticky plants burs on its fur– Wind carrying dandelion seeds to another field

The facts of ecosystems• If an organism is brought by a human from one

part of the world to another, it is considered an EXOTIC species.

• Limiting factors include COMPETITION and PHYSICAL BARRIES (ocean).

• Different continents can have similar climates. For example, the antelope in AFRICA occupies the same NICHE as the kangaroo in AUSTRALIA.

More facts of ecosystems

• The DESERT receives less that 25 centimeters of rain each year.

• Ponds and rivers are two types of FRESHWATER biomes, while the OCEAN would be a marine biome.

Rainforests & Estuaries….• Rainforests ROCK! They boast: – Canopy– Understory– High number of plant and animal species

• Estuaries are EXCITING! – Large supply of nutrients– Mix of freshwater and saltwater– Calm waters, good for breeding