- "Ecology Principles and Organism Interactions" -

1. Principles of Ecology • AL COS • 3, 6, 23, 24, 25, 38, 39, 41 • AHSGE • Standard I Objective 1 • Analyze the methods of science used to identify and solve problems. • Standard II Objective 1 • Trace the transfer of matter and energy through biological systems. • Standard VI Objective 1 • Demonstrate an understanding of factors that affect the dynamic equilibrium of populations and ecosystems.

2. Organisms and their environment a. Ecology 1. Scientific fields 2. Methods used b. Abiotic factors c. Biotic factors Levels of organization in ecology a. Organisms b. Populations c. Communities d. Ecosystems e. Biosphere Three major types of ecosystems a. Terrestrial b. Fresh water c. Salt water Additional notes Three main types of symbiosis a. Commensalism b. Mutualism c. Parasitism Nutrition and energy flow a. The sun b. Autotrophs c. Heterotrophs d. Decomposers Food chain and trophic level Food web Ecological pyramid Water cycle, Carbon cycle, Nitrogen cycle, Phosphorus cycle Teacher resources Principles of Ecology Outline

3. Organisms and Their Environment • Ecology is the scientific study of interactions among organisms and their environment. • The study of how living things relate to each other and to their environment • The biosphere is the portion of Earth that supports life • An ecosystems biotic and abiotic factors • The nonliving parts of an organism’s environment are the abiotic factors • Ex. Air currents(wind), temperature, moisture, light, soil, humidity, and rocks • All the living organisms that inhabit an environment are called biotic factors.

4. Levelsof Organization(Classification) in Ecology • Organisms • Populations • A group of organisms of one species that interbreed and live in the same place at the same time. • Competition may occur if resources(food, water, etc) are in short supply. • Communities • Made up of several interacting populations. • Ecosystems • Made of the interactions among the populations in a community and the abiotic factors • Ecosystems are studied by ecologists • Ecosystems are made up of organisms, populations, and communities • Biosphere • Includes from high in the atmosphere to the bottom of the ocean.

5. Three major kinds of ecosystems • Terrestrial- on land • Ex. Forests, meadows, and desert scrub • Fresh water • Ex. Ponds, lakes, streams • Salt water (Marine) • 75% of the Earth’s surface

6. A habitat is the place where an organism lives out its life. • A niche is the role and position a species has in its environment---how it meets its need, how it reproduces, and how it survives. • Predators area animals that kill and eat other animals. • The animals that are eaten are called prey • Predator-prey relationships • The relationship in which there is a close and permanent association among organisms of different species is called symbiosis.

7. 3 Main types of symbiosis • Commensalism- one species benefits and the other species is neither harmed nor benefited. • Ex. Spanish moss • Mutualism- two species of organisms benefit • Ex. Ants and an acacia tree • Parasitism- one organism benefits at the expense of another, but usually does not kill the host. • Ex. Ticks

8. Nutrition and energy flow • The ultimate source of energy is the sun. • Producers(Autotrophs)- make their own food.(use energy from the sun or energy stored in chemical compounds to manufacture their own nutrients • Ex. Plants, some unicellular organisms • Consumers(Heterotrophs)- consume other organisms for their energy • Obtain energy and nutrients from autotrophs • Omnivores, carnivores, herbivores, scavengers, and decomposers are all consumers • Ex. Animals, humans

9. Three types of heterotrophs • Carnivores- kill and eat other animals • Ex. Lions • Scavengers- animals that eat animals that have already died • Ex. Black vultures • Omnivores- eat both plant material and animals • Ex. Humans, raccoons, opossums, bears • Decomposers- organisms that break down and absorb nutrients form dead organisms. • Before plants can reuse many organic materials, the materials must be broken down by decomposers • Ex. Most fungi, some protozoans, many bacteria

10. Food chain- a simple model that scientists use to show how matter and energy move through an ecosystem. • Only shows one route for the transfer of matter and energy. • Usually has three links but no more that five. • At each link a portion of energy is lost as heat, therefore, the amount of energy remaining in the 5th link is low. • Trophic level- a feeding step in the passage of energy and materials. • Pg 50-51

11. Food web- expresses all the possible feeding relationships at each trophic level in a community. • Network of interconnected food chains • Trophic level and food chain are parts of a food web • A more realistic model because most organisms depend on more than one other species for food. Food chain and food web movie

12. Ecological pyramid- shows how energy flows through an ecosystem. • The base of the pyramid, or 1st trophic level are the autotrophs. • The total transfer from one level to the next is only about 10% because energy is lost due to heat. • A pyramid of biomass expresses the weight of living material at each trophic level. • How to calculate biomass: • Find the average weight of each species at that trophic level and multiply by the estimated number of organisms in each population.

13. The Water Cycle • In the water cycle, water is constantly moving between the atmosphere and Earth. • Pg 55 • Water is lost to the abiotic parts of the biosphere from the biotic parts by the process of transpiration • Water, carbon, and nitrogen are released back into the atmosphere during decomposition Water cycle movie

14. The Carbon Cycle • Carbon cycle begins with autotrophs. • During photosynthesis carbon is converted from carbon dioxide gas. • Heterotrophs eat the autotrophs and then release carbon dioxide gas.

15. The Nitrogen Cycle • Plants use nitrogen to make proteins. • Herbivores eat the plants and convert the proteins into human proteins. • Nitrogen is released to the abiotic parts of the biosphere from the process of death and decay by bacteria. • Lightning and certain bacteria convert the nitrogen in the air into more usable forms.

16. The Phosphorus Cycle • The phosphorus cycle is different from other cycle because phosphorus is found in sedimentary rock, not the atmosphere. • Two cycles: • Short term: phosphorus is in the soil and plant life • Long term: phosphorus is washed into the sea

17. Teacher Activities/Labs • Food web activity-Gar Gar Gator • SIM Lab: Owl pellet(SIM lab disc required) • SIM Lab: BioAssessment (SIM lab disc required) • SIM Lab: Water Quality (SIM lab disc required) • SIM Lab: Stream in a Bucket (SIM lab disc required) • SIM Lab Soil Testing: (SIM lab disc required) • AHSGE Pathways Lab: Grabbing for Grub(Teacher) • AHSGE Pathways Lab: Gone Fishing(Teacher) • AHSGE Pathways Lab: Producers-Consumers-Decomposers (Teacher) • AHSGE Pathways Lab: Pass The Energy Please(Teacher) • AHSGE Pathways Lab: Cycles of Nature(Teacher) • Food Webs in the Bay