1. The Biosphere

2. Ecology
the scientific study of interactions among organisms and between organisms and their environment
Plant Biome Ecosystem Community Population Species
Biome: a group of ecosystems that share similar climates and typical organisms
Ecosystem: All organisms that live in a place together within their environment
- abiotic factors interacting with biotic factors
Community: Different populations that live together in a defined area
- forest plants, animals, and fungus interacting
Population: individuals that belong to the same species and live in the same area
- a group of Bison living in the same area
Species: similar organisms that can breed and produce fertile offspring

3. Environmental Factors
biotic factors: any living part of the ecosystem in which organisms can interact
Example: Bullfrog
tadpole→ eats algae
bullfrog→ insects
Other species competing with the bullfrog for food
abiotic factors: physical components of an ecosystem (environment)
Examples: sunlight, tornados, wind

4. Energy Consumption: Producers
Organisms need energy to carry out daily functions→ metabolism, reproduction, growth
They cannot produce energy; they need to get it from other sources
Autotrophs (producers): organisms that can convert energy from the sun into useable energy
Example: bacteria, algae, plants
Primary producers are essential to life on Earth because they produce the essential energy for other living organisms

5. Photosynthesis: capturing light energy to transform carbon dioxide and water into oxygen energy-rich carbohydrates (sugars)
Equation: light + CO2 + H2O → C6H12O6 +O2
Without photosynthesis, there would not be enough oxygen to breathe
Chemosynthesis: taking in carbon dioxide, hydrogen sulfide, and oxygen to produce carbohydrates (sugars) and sulfur
Chemosynthetic organisms live in harsh environments
deepest part of the ocean
deep-sea volcanic vents
hot springs

6. Energy Consumption: Consumers
Heterotrophs (consumers): organisms that have to aquire energy from other organisms through ingestion
Example: birds, cheetah, snakes
6 Types of Consumers
Carnivores: kill and eat other animals
Examples: tiger, alligator,
Scavengers: animals who eat other dead animals that have already been killed
Example: vulture
Decomposers: feed by chemically breaking down organic matter
Examples: bacteria, fungi

7. Energy Consumption: Consumers
4. Herbivores: organisms that obtain energy through eating plants
Examples: cows, caterpillars
5. Omnivores: organisms who eat both animals and plants
Examples: Humans, pigs
6. Detritivores: feed on detritus (waste or debris) material
Examples: snails, shrimp
The categories are in place but they do not always remain 100% -- extrenuating circumstances may push an organism to obtain energy any way they can

8. Energy Flow: Food Chains/Webs
Energy flow through an ecosystem is one-way
food chain: series of steps in wihch organisms transfer energy
Food Chain

9. Energy Flow: Food Chains/Webs
food web: a network of feeding interactions
Food webs are more complicated than a simple food chain
Food chains are found within food webs
Are decomposers important?
YES! They recycle nutrients to feed the primary producers.
Food Web

10. Trophic Levels/Ecological Pyramids
trophic level: each step in a food chain or food web
ecological pyramids: shows the relative amount of energy or matter in each trophic level
Any energy that is passed on to the next level is stored in the organisms
Not all energy moves to the next trophic level→ it is released as heat
About 10% moves on to the next level→ divide by 10

11. Trophic Levels/Ecological Pyramids

12. Biomass/Numbers Pyramids
A pyramid of biomass illustrates the relative amount of living organic matter available at each trophic level
A pyramid of numbers shows the relative number of individual organisms at each trophic level
As you increase through the pyramid, the biomass and the numbers decrease
Biomass decreases because there are less numbers as you travel through the pyramid

13. Cycles of Matter: The Water Cycle
Water continuously moves between the oceans, atmosphere, and land
The Water Cycle
Water becomes vapor in the process of evaporation
transpiration: water evaporating from the leaves of plants
As water cools and condenses (condensation), it falls to the Earth in the form of precipitation
Groundwater: precipitaiton that is soaked into the ground and taken up by plants
Runoff: Precipitation that enters a stream, river, or lakes

14. Water Cycle

15. Cycles of Matter: Carbon Cycle
Carbon is a major component in all organic compunds, such as carbohydrates, lipids, and proteins
Coal, oil, and natural gas are referred to as fossil fuels because they are fossilized carbon
The Cycle
Plants take in CO2 during photosynthesis and convert it to carbohydrates
Animals eat the plants and absorb the carbohydrates
Animals exhail CO2 back into the atmosphere
When animals die, they are decomposed and the carbohydrates become rocks or fossil fuels

16. Carbon Cycle

17. Cycles of Matter: Nitrogen Cycle
All organisms required nitrogen to make amino acids→ building blocks of protein
Forms of Nitrogen
N2→ nitrogen gas makes up 78% of the atmosphere
NH3→ ammonia
Only certain bacteria can use nitrogen directly (nitrogen fixation)
primary producers consume the ammonia, nitrates, or nitrites

18. The Nitrogen Cycle
Bacteria turns nitrogen into ammonia, nitrites, or nitrates
Primary producers consume the nitrogen and make proteins
Consumers eat the plants, which makes nitrogen compounds
Decomposers break down the nitrogen in dead consumers
Humans add nitrogen to the atmosphere through fertilizers
Small amounts of nitrogen are converted into usable forms by lightning

19. Nitrogen Cycle

20. Cycles of Matter: Phosphorus Cycle
Phosphorous is essential because it is a part of DNA and RNA
It is NOT abundant in the atmosphere
The Phosphorous Cycle
Phosphates are released when rocks and sediments are worn down
Plants bind the phosphates when they take it up through the roots
It moves through the food web from producers to consumers
Other phosphates wash into the river where it dissolves

21. Phosphorous Cycle