Agenda 10/25 and 10/26 Intro to ecology lecture Constructing food webs activity Nutrient acquisition practice Turn in: WB and video notes Homework 1. WB 122, 123, 124 2. Nutrient Acquisition Worksheet

Abiotic vs. Biotic Factors Sort the cards with your group into categories that make sense Be prepared to explain your rationale behind your groups

Abiotic vs. Biotic Factors Sort the cards with your group into categories that make sense Be prepared to explain your rationale behind your groups Discussion questions: Can non living things affect living? Do plants and animals have similar or different roles in an ecosystem? Can biotic factors affect other biotic factors? During the video, list as many abiotic and biotic interactions as you can find https://www.youtube.com/watch?v=GibiNy4d4gc

Levels of Organization in an Ecosystem Species- a group of organisms that can potentially interbreed to produce fertile offspring Ex: Zebras Population- A group of species that are reproductively isolated from others Ex: Zebras living in a specific grassland Community- populations of different species living together and interaction with each other Ex: Zebras, lions, tigers, hyenas living together Ecosystem- communities interacting with abiotic and biotic factors Ex: zebras, lions, tigers, hyenas living together in the climate, temperature, precipitation, near rocks, drinking water

Ecological Roles Autotrophs- create their own food using sunlight and photosynthesis Also called producers Obtain nutrients from an abiotic source Heterotrophs- consume something else for food Also called consumers Obtain nutrients from a biotic source The sun allows an ecosystem to be sustainable as there is always energy going into the system

Autotrophs vs. Heterotrophs

Food Webs The arrow points in the direction of energy flow Example: The grass gives it energy to the bunny DO NOT REVERSE THE ARROWS! Explain two potential effects of removing the deer from the ecosystem

Roles within a food web Autotrophs- obtain inorganic nutrients from abiotic environment (sun, photosynthesis) Consumers- heterotrophs that feed on other living organisms by ingestion Saprotrophs- heterotrophs that obtain organic nutrients from dead organisms by external digestion Ex: bacteria, fungi Detritivores- heterotrophs that obtain organic nutrients from detritus by internal digestion Ex: Earth worms

What are some interactions that occur in an ecosystem?