Organisms and Their Environment

2. Organisms and Their Environment

3. Ecology • Scientific study of interactions among organisms and their environment. • Reveals relationships among living and nonliving • Interdisciplinary (Math, chemistry, physics, geology)

4. Biosphere Portion of the Earth that supports life. High in atmosphere to bottom of oceans

5. Abiotic Factors • Non-living parts of an organisms environment. • Air currents, temperature, moisture, light and soil • Help determine if organism can survive

8. Levels of Organization

9. Levels of Organization • Population-Group of organisms of one species that interbreed and live in the same place at the same time. • Community—Collection of interaction populations.

10. Ecosystem—Interactions among populations in a community (physical surroundings, or abiotic factors) Terrestrial ecosystems forests, meadows, desert scrub Aquatic Freshwater (ponds, lakes, and streams) Saltwater/Marine (75% Earth’s surface)

11. Organisms in Ecosystems • Habitat—Place where an organism lives out its life. • Niche—Role and position a species has in its environment (food, shelter, survives, reproduces) Hummingbirds have long beak to get nectar deep in flowers, important niche, reduces competition.

12. Relationships • Symbiosis-Relationship in which there is a close and permanent association among organisms of different species.

13. Commensalism—One species benefits and other species is neither harmed nor benefits. Mutualism—Both species Benefit

14. Parasitism-One organism derives benefit at the expense of other.

15. Nutrition and Energy Flow

16. The producers:AUTOTROPHS • Organisms that use energy from the sun or energy stored in chemical compounds to manufacture their own food. • auto (Greek) self • trophe (Greek) nourishing • Plants, some uni-cellular organisms

17. The Consumers: Heterotrophs • Organism that can not make their own food and must feed on other organisms. • hetero (Greek) other • trophe (Greek) nourishing

18. Types of Heterotrophs • Herbivore-Heterotrophs that feed only on plants. • Herba (Latin) grass; vorare (Latin) devour • Rabbits, grasshoppers, squirrels, bees, elephants • Carnivore-Animals that kill and eat other animals • caro (Latin) flesh; vorare (Latin) devour • lions • Scavengers (Eat animals already dead; leftovers) vultures • Omnivore-Animals that eat both plants and other animals • omnis (Latin) all; vorare (Latin) to devour) • Humans, raccoons, opossums, bears

20. Decomposer

21. Matter and Energy Flow

23. Food Chain- Simple model used to show how matter and energy move through an ecosystem

24. Arrow indicates direction which energy is transferred from one organism to the next. • Always between 3 and 5 Links (4 shown) • Amount of energy remaining in fifth link is only a small portion of what is available at the first link (lost heat)

25. Trophic Levels– Feeding Steps Bacteria and Fungi decompose all links in food chain when organisms die.

26. Food Web Express all the possible feeding relationships at each trophic level in a community

27. Ecological Pyramid • Energy flow through an ecosystem • Base-autotrophs-first trophic level • Higher trophic levels are layered on top of one another. • Initial source of energy is the sun.

28. Energy/Population size/Biomass decrease as trophic levels increase

29. Each bar represents the population size within a trophic level.

30. Each bar represents the amount of biomass with in trophic level.

31. Pyramid of Energy Each bar represents the energy available within a trophic level

32. On average, each feeding level only contains 10% of the energy as the one below it • Loss as heat and organisms processes 10,000 units (calories) Producers  herbivores would receive 1000 units primary carnivores 100 units  secondary carnivores 10 units.

33. Humankind’s Worst Enemy Which mammal has killed more humans, destroyed more things, and spread more disease than any other? You might think the answer is humans, but it’s rats. Rats destroy a fifth of the world’s food supply. Most rat damage to the food occurs where there is little food to spare. The Indian rice destroyed by rats could feed 250 million people a year. Rats spread disease, including the bubonic plague, which killed a third of the people in medieval Europe. All the wars in history have not done as much damage as rats. Surely rats are peoples worst enemy. What are some things rats might be good for? This might take a while.

34. Cycles in Nature Water Cycle Carbon Cycle Nitrogen Cycle Phosphorus Cycle

36. Evaporation--A change from liquid to vapor form (lakes and oceans). Surface water to Atmosphere Precipitation--falling products of condensation in the atmosphere, as rain, snow, or hail. Transpiration--The process of giving off vapor (plants, skin) Water Cycle (Hydrologic Cycle)Water constantly moves between atmosphere and earth.

37. Water Cylce Condensation—Water Vapor to Liquid. Produces clouds and fog Run Off—water moves across land. As flows may infiltrate into the ground, evaporate into the air, become stored in reservoirs, or extracted for agricultural and human uses.

40. Human Impact on Water Cycle Agriculture Alteration of chemical composition of atmosphere Construction of dams\ Deforestation and afforestation Removal of groundwater from wells Water abstractions from rivers Urbanization

42. Carbon Cycle Exchange of carbon between biosphere, geosphere, hydrosphere and atmosphere. • Atmosphere provides Carbon Dioxide • Autotrophs use carbon dioxide to make carbon rich molecules (photosynthesis) • Autotrophs and heterotrophs break down high energy carbon molecules and release carbon dioxide as WASTE.

43. Carbon taken from atmosphere Plants bring in CO2 from atmosphere for photosynthesis Enters through water as oceans near poles cool and are able to dissolve more C02

44. Carbon released back into atmosphere Respiration- Endothermic Reaction; Breaks down glucose into CO2 and water. Decay of Animal and Plants ( Decomposers break down carbon molecules and convert into CO2) Combustion of organic materials- Burning fossil fuels (coal, petroleum, natural gas)

45. Limestone Reactions- (calcium carbonate) Breaks down into CO2 Warmer water releases CO2

46. Carbon Recap • Autotrophs use CO2 from air to make organic molecules • Carbon transferred to heterotrophs when eat plants; uptake by decomposers • Most carbon back into air through respiration • Dead organic matter incorporated into land.

50. Nitrogen CycleTransfers nitrogen and nitrogen-containing compounds • Earth atmosphere is 78% Nitrogen. • Essential for amino acids; nucleic acids; photosynthesis.