BIOL 1103 1st Edition Lecture 3 **Finished up LECTURE 2:Community Interactions**Started and Finished: ENERGY FLOW and NUTRIENT CYCLING in ECOSYSTEMS- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - **Finished up LECTURE 2:Community InteractionsPARASITISM and MUTUALISM- Parasites and Hostso Parasites: live IN or ON their prey, Aslso called HOSTSo Hosts: harm and weaken, however do not always kill right away. - Parasite-Host relationships:o Act as agents of NATURAL SELECTION on one another. (Good and Bad) Ex of ‘GOOD’: people can live with HIV for 30+ years and pass on to future hosts  Ex of ‘BAD’: Ebola: kills host really fast, so it can spread fasto Symbiotic: long-term physical relationship Ex: Whale/Certain ants- Mutualism: interaction between species which BOTH species benfit. o Many MUTUALISTIC relationships are SYMBIOTIC: long-term relationship Ex: Lichen: looks like one species but is actually two: - Fungus and plant living together: fungus feeds plant part and plant part feeds off the fungus part. How Community Interactions Cause Change Over Time- Succession: is a Process/Order1. Early organisms modify the environment in ways that favor later organisms2. End-stage organisms suppress earlier organisms but tolerate one another, producing a stable community3. There is a general trend toward more species and longer-lived speciesThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- SUCCESSION: Begins with an Ecological disturbance  Starts with PIONEERS: hardy plants, which change the ecosystem in ways that FAVOR competing plants, which eventually DISPLACE the PIONEERS.  If continued, Succession progresses to a diverse and stable CLIMAX COMMUNITY- Two Forms of SUCESSION:1. PRIMARY: community GRADUALLY forms in a location where there are no remnants of a previous communitya. EX: Volcano/ Asteroid Hitsb. TIME SPAN: 1,000 years, pretty LONG time2. SECONDARY: new community develops after an EXISTING ecosystem is disturbed in a way that leaves significant remnants of the previous community behind, such as soil and seeds. a. Ex: Yellowstone National Park/ Forest Fireb. TIME SPAN: 100 years, SHORTER time span. - Succession CLIMAX COMMUNITY: populations that can coexist without replacing one anothero CLIMAX COMMUNITIES: have more species and more types of community interactions than do earlier stages of succession**Started and Finished: ENERGY FLOW and NUTRIENT CYCLING in ECOSYSTEMSLECTURE 4: ENERGY FLOW and NUTRIENT CYCLING in ECOSYSTEMS*ECOSYSTEMS have 2 Components1) BIOTIC  LIVING organisms2) ABIOTIC  NON-living physical or chemical aspects of the environment. NUTRIENTS: atoms and molecules that are NECESSARY for life. - Nutrients are CYCLICAL tansported around earth, but don’t leaveo Ex: Humans: food  energyo Ex: Plants: glucose  energy- ENERGY is UNIdirectional  Passed from one TROPHIC level to the NEXTo Energy Heat  given off to environmento Energy (sun)  producers  energy is lost in form of HEAT and the creation of Energy (making bark for example)o * Nutrients are never really lost- Energy cycle:- photosynthetic organisms- passes through levels of NONphotosynthetic organisms- Each category of organisms is called a trophic level - TROPHIC LEVELS- Producers (or autotrophs)  make their own food using inorganic nutrients and solar energy from the environment- Ex: Photosynthesis - Consumers (or heterotrophs)  Organisms that cannot photosynthesize - Ex: Humans Levels of CONSUMERS: - Primary consumerso Herbivores include animals such as: Grasshoppers mice zebras, o and FORM the second trophic level- Secondary consumerso Carnivores: feed off primary consumers:  Ex: Hawk who eats the rabbit- Tertiary (etc.) consumers- Net Primary Production in Ecosystems: Energy is lost at EACH Trophic level = never 100% in the end- Why? Because not all energy can be digested:- Ex: hawk eats rabbit, Bones are waste- 10% Law: Each Trophic level loses 10% each time used- Energy flows through Ecosystems by:1. Food Chains:a. Simple Terrestrial food chainb. Simple Marine Food Chaini. Ex: Producer: PLANT: PHYTOPLANKTON (First Trophic level) ii. Primary Consumer: WORM: ZOOPLANKTON, SHRIMP (Secondary Trophic Level)  iii. Secondary Consumer: BIRD: SMALL FISH (Thirst Trophic Level) iv. Tertiary Consumer: HAWK: BIGGER FISH (Fourth Trophic Level) v. Quaternary Consumer: SHARK: (Fifth Trophic Level)2. Food Webs: (Simplified Grassland Foodweb)a. Buffalo: Primary Consumerb. Energy source Consumer: Pack of wolves can eat Buffaloc. Decomposers: microorganisms/bacteria/etc… degrades the remains  replenishes the energy into the system *LOW energy contribution* Energy loses efficiency as it moves down the Trophic levels. ▫ The average net energy transfer between trophic levels is roughly 10% efficient and is known as the “10% law” Energy pyramid:▫ Lower Trophic  less you need to eat to achieve Nutrients requirements▫ Ex: Eat and apple Primary consumer: easier to break down and faster energy▫ Ex: Eat Turkey  secondary Consumer: takes longer to break down and metabolize - Nutrient Cycling: o MACROnutrients: needed in Large amounts Water – Carbon Hydrogen – Oxygen Nitrogen – Phosphorous Sulfur – Calciumo MICROnutrients: needed in small amounts Zinc – Molybdenum Iron – Selenium Iodine- Nutrient Cycles:o Hydrologic Cycle Reserviors Water vapor in Atmosphere/ Lakes/ Rivers/ Ocean/Underground Water Processes Precipitation/ Rain/ Evaporation/ Run off from Rivers/ Seepage through soil into groundo *Carbon Cycle:  Reservoir CO2 in Air/ CO2 dissolved in ocean/ Fossil fuels in ground- nutrient in ABUNDANCE: CO2  Processes Burning fossil fuels/ Fire/ Photosynthesis/ Respiration/ Decomposition- Plants photosythesis Glucose made into energy- Animals cellular respiration  Trophic Levels  - 1) Producers- 2) Consumers- 3) Detritivores and Decomposerso Carbon Cycle: much of earths carbon is on Limestone Rock.  Fossil Fuels: coal, oil, and natural gas, are additional long-term reservoirs for carbonHUMAN DISRUPTION OF EARTH- Ancient People: had relatively little impact on nutrient cycles  HOWEVER, as population grew and technology