1. Chapter 3: The Biosphere
Section 1: What is Ecology

2. Ecosystems
Ecology - the study of interactions between organisms and the living and nonliving components of their environment.

3. Studying Out Living Planet
Biosphere – the area on and around Earth where life exists
includes anywhere that life exists
Population: All the members of one species that live in a particular area
Community: All of the different species that live in a particular area
Ecosystem: includes all of the organisms and the nonliving environment found in a particular place
includes living and nonliving things
example: everything living and nonliving in a pond
Changes within in organisms(predators, prey, etc) can impact the whole ecosystem

4. Biotic Factors – living things that affect an organism
examples: plants, animals, bacteria, fungi
Abiotic Factors – nonliving things that affect an organism
examples: temperature, humidity, pH, oxygen concentration
The mix of biotic and abiotic factors is what shapes every environment

5. Chapter 3: The Biosphere
Section 2: Energy, Producers, and Consumers

6. Primary Producers Autotroph: Organisms that make their own food
Ex: thorough photosynthesis using sunlight
Plants & Algae
Ex: through chemosynthesis using chemicals
Bacteria
Autotrophs do more than make food for themselves, they also store energy for the organisms that consume them.
Autotrophs are the initial food source for all food chains & webs.
This is why autotrophs are called primary producers.
Primary Producer: the first producers of energy-rich compounds that are later used by other organisms
Primary producers are essential to the flow of energy through the biosphere

7. Consumers
Consumer: Organism that relies on other organisms for energy and nutrients
Animals, Fungi, & some Bacteria
Heterotroph: Must acquire energy from other organisms by ingesting (eating) them in one way or another.

8. Chapter 3: The Biosphere
Section 3: Energy Flow in Ecosystems

9. Food Chains & Food Webs
Food Chain – a single pathway showing the feeding relationships among organisms
Series of steps that show the transfer of energy by eating and being eaten

10. Food Web – a complex diagram showing many food chains put together.
There interconnected food chains within food webs
Food webs star with producers and end with top predators, decomposers, or detritivores

11. Types of Consumers Carnivore: kill and eat other animals
EX: Snakes, Dogs, Cats
Scavenger: consume the carcasses of other animals that have been killed by predators or have dies of other causes
EX: Vulture
Decomposer: chemically break down organic matter
EX: Bacteria & Fungi
Herbivore: consume plant leaves, roots, seeds, or fruits
EX: Cows, Deer, & Caterpillars
Omnivore: consume a variety of food including both plants and animals
EX: Humans, Bears, & Pigs
Detritivore: consume detritus particles (decomposed matter) and decomposers
EX: Snails, Shrimp, Mites, & Earthworms

13. When there is a change in the number of predators or prey, the entire ecosystem can change
Many organisms at the top of the food chain do not have predators in nature
Ex: Killer Whale

14. Trophic Levels & Ecological Pyramids
Trophic Level: Each step in a food chain or food web
Primary producers always make up the first trophic level & various consumers occupy every other level
Ecological Pyramids: show the relative amount of energy or matter contained within each trophic level in a given food chain or food web
Pyramids of Energy: Shows the relative amount of energy available at each trophic level or a food chain or food web.
Only 10% of the energy from the lower step of the pyramid is passed on to the next step of the pyramid.

15. Chapter 3: The Biosphere
Section 4: Cycles of Matter

16. Recycling in the Biosphere
Unlike the one-way flow of energy, matter is recycled within and between the ecosystem
Biogeochemical Cycles: elements pass from one organism to another and among parts of the biosphere through closed loops that are powered by the flow of energy
Consists of biological processes, geological processes, and chemical processes.
Human activity also plays a large roll.

17. Biological Processes: includes any and all activities performed by living organisms
Ex: breathing, “burning” food energy, & eliminating water products
Geological Processes: include volcanic eruptions, the formation and breakdown of rock, & major movements of matter within and below the surface of the earth
Chemical & Physical Processes: includes the formation of clouds and precipitation, the flow of running water, & the action of lightning
Human Activity: include the mining and burning of fossil fuels, the clearing of land for building and farming, the burning of forests, & the manufacture and use of fertilizers

18. Water Cycle
Water cycle continuously moves water between the atmosphere, the land, & the oceans
Water vapor condenses & falls to earth’s surface: precipitation
Some water percolates into the soil & becomes groundwater
Water is heated by the sun & reenters the atmosphere by evaporation
Water also evaporates from trees & plants by transpiration
Transpiration is the process where water travels through a plant and evaporates from the leaves as water vapor

20. Nutrient Cycles
Every organism needs nutrients to build tissues and carry out life functions. Like water, nutrients pass through organisms and the environment through biogeochemical cycles. The three pathways, or cycles that move carbon, nitrogen, and phosphorus through the biosphere are especially critical for life.

21. Carbon & Oxygen Cycles
All organisms are made of carbon(organic matter)
Animals, plants, & other photosynthesizing organisms play an important role in cycling carbon & oxygen through an ecosystem
Plants use CO2 in air to build organic molecules during photosynthesis
Also in photosynthesis O2 is released
Many animals use O2 to help break down organic molecules which releases energy & CO2
Plants again take in the CO2
Respiration: The process of exchanging of O2 & CO2 between organisms & their surroundings

23. Carbon & Oxygen Cycles
Combustion: burning of substance; releases carbon into the atmosphere
All living things have carbon in them; burning living things release CO2
Decomposing of living things also releases CO2
Fossil fuels(oil & coal) are made of remains of dead animals & plants; therefore the burning of fossil fuels releases CO2

25. Nitrogen Cycle Nitrogen gas (N2) makes up 78% of the atmosphere.
Bacteria in the soil convert N2 into ammonia through the process of nitrogen fixation.
Plants use the ammonia to make proteins and DNA/RNA.
Animals eat the plants and digest the proteins and DNA/RNA.
Animals return the nitrogen to the soil through urine and feces.
Bacteria obtain energy by converting nitrates into nitrogen gas, which is released into the atmosphere in a process called denitrification.

27. Phosphorus Cycle Phosphorus forms the molecules in DNA & RNA
Phosphorus is found in inorganic remains, phosphate rock and soil minerals, & in dissolved phosphate and phosphate sediments in the ocean
Phosphate cycles between organisms and the soil on land
Organic phosphate cycles through the food web from producers to consumers and to the rest of the ecosystem
Some phosphate is washed into the water and eventually makes it to the ocean where marine organisms process and incorporate it into biological compounds

29. Nutrient Limitation
If ample sunlight and water are available, the primary productivity of an ecosystem may be limited by the availability of nutrients
Limiting Nutrient: the nutrient whose supply limits the productivity of an ecosystem
We supplement the nutrient limitation in soil by using products like fertilizers to supplement nutrients that would limit productivity
In the oceans when there are large amounts of run off that come from land after a heavy rain or storm there is suddenly an increase in nutrients which can spike growth & productivity