Transcript Ecology
Chapter 2 Section 2-1 Organisms and Their Environment Ecology The branch of Biology that studies the interactions between organisms and their environment, (living and nonliving) Ecology How do you use Ecology in your life? Food- planting, hunting, fishing Pets- fleas/ticks, cleaning, food, range Survival- soccer team in Andes “life” Garbage- compose, leaves, recycling Energy- solar, hybrid, water Ecological Questions??? • • • • Why do birds migrate? Why does a lizard camouflage itself? Why might a forest fire be beneficial? What are some affects of acid rain? Ecology Ecology as a science was developed in the 1960’s as man began to realize the profound effect of his actions on the living world. Tropical Rainforest Example Why is it important to us? – ½ world’s species (loss of species) – Deforestation for logging • Lower O2 production, Increase CO2 production • Global Warming caused by Greenhouse Effect – Why don’t they just stop? • Poor countries / Poor individuals Ecology Biotic vs. Abiotic Factors Biotic – living factors in the environment Abiotic – nonliving factors in the environment 7 abiotic factors- can you name them? Seven abiotic factors 1. 2. 3. 4. 5. 6. 7. Soil Temperature Moisture/ Water Light Wind Air Composition (O2) Natural Disasters Abiotic vs. Biotic Factors Ground Mole Biotic Abiotic Other moles Roots Grubs Predators Humans Soil type Moisture Temperature Try these: Bird, Deer, Street Person Ecology • Bird, Deer, Street Person Ecology Ecosystems Area where organisms interact with one another and the living and nonliving environment Ecology Population vs. Community Population – a group of organisms of the same species living in an ecosystem Community – all the populations in a given area Ecology Levels of Organization Page 40 Biosphere (all ecosystems) Ecosystem (living and non-living) Community (all species) Population (one species) Organism (individual) Ecology • • • • • Track a deer for one year Role of a deer and interaction with its herd The affects of vegetation on deer movement Affects of a harsh winter on deer Global population of deer Ecology Habitat vs. Niche Habitat – the place where an organism lives Niche – the role of an organism in a community “total way of life” Ecology • Habitat- where it lives – Birds- forest tree nest – Dead Log Habitat • Niche- role in the community – Food, space, conditions • Temperature, time of feeding, type of food • Two organisms cannot share a niche Quiz 1. Give one biotic factor, abiotic factor, the habitat and niche of a Lion. 2. Give the habitat and niche of a shark. 3. List the 5 levels of organization, beginning with organism. 4. How many of the 7 abiotic factors can you list? 5. What are the 2 main reasons for saving the rainforests? Symbiosis- “Living Together” A close and permanent association between organisms of different species 1. Mutualism 2. Commensalism 3. Parasitism Types of Symbiosis Mutualism – both species benefit Examples • Legume plants and nitrogen-fixing bacteria • Ants and acacia trees (pg.44) • Bacteria and cow • Bird and crocodile • Bees and flowers Types of Symbiosis Commensalism – one species benefits and the other is neither harmed or benefited Examples - Remora and shark - Bird and cattle - Orchids, mosses and ferns on a tree Types of Symbiosis Parasitism – one organism benefits and the other is harmed, but usually not killed Examples 12345 - Australian Rabbits - Virus, bacteria, flukes, tapeworms - Ticks, mosquitoes, leech, lamprey * Vaccinations (prevention) smallpox and polio Chapter 2 Section 2-2 Pages 46-57 Autotrophs vs. Heterotrophs Autotrophs – organisms that make their food (self-feeder) Photosynthesis and Chemosynthesis (50% efficient) Autotrophs vs. Heterotrophs Heterotrophs – organisms that depend on others for nutrients (other-feeder) They cannot make their own food, they must consume it. (10% efficient) Autotrophs vs. Heterotrophs • Why do you think autotrophs are more efficient than heterotrophs? Ecology Roles of Organisms in an Ecosystem Producers – autotroph’s that change the sun’s energy into chemical energy in organic molecules during photosynthesis Examples – green plants and algae Ecology Consumers- heterotrophs Herbivore – “plant-eaters” feed only on producers Carnivore – “meat-eaters” feed only on consumers Omnivores – eat both plants and animals - feed on producers and consumers - advantage or disadvantage? Ecology Roles of Organisms in an Ecosystem Scavengers – animals that feed on other dead animals Examples – vulture, buzzard, maggots Ecology Roles of Organisms in an Ecosystem Decomposers – organisms that break down dead organic material Examples – fungi and bacteria Trophic Level- Feeding step Producers First Order Consumers – herbivores (mouse) Second Order Consumers – carnivores (raccoon) Third Order Consumers – larger carnivores (large cats, wolf) Food Chains Model showing how matter and energy move through an ecosystem. Shows only one organism feeding on another. Food Chain Sun Producers 1st order consumer 2nd order consumer 3rd order consumer Decomposers Each arrow (→) represents energy flow Each step represents a trophic level Food Chain Food Web - Model showing all possible feeding relationships at each trophic level in a community. - Network of interconnected food chains - Many options for food Food Web Water Cycle Evaporation/Transpiration → Condensation → Precipitation (4 Types) → Runoff/Groundwater Water Cycle Carbon Cycle Carbon is found in the environment as carbon dioxide gas (CO2) How does carbon get into the environment? - Burning fossil fuels, forests and organic material - Respiration Carbon Cycle - CO2 is used by producers for photosynthesis carbon dioxide + water = simple sugars. - Sugars passed to consumers eating them. Nitrogen Cycle Nitrogen-fixing bacteria convert atmospheric nitrogen into useful compounds (legume plants- bean) Legumes convert nitrogen into nitrates. Nitrogen Cycle - Herbivores convert plant proteins into animal proteins. - Animal proteins are then passed to consumers - Organisms return nitrogen to the environment when they die or defecate Phosphorus Cycle Phosphorus is a mineral that come from the breakdown of rocks. Plants use phosphorous from the soil in their body tissues and it passes to each consumer. How long is this cycle? Stranded on an island! A small group of people are stranded on a barren island. They have 500 bushels of wheat and one cow. What should they do to survive for the greatest length of time? Stranded on an island! a. Eat the cow and then the wheat b. Drink the cow’s milk, eat the cow, then eat the wheat c. Don’t feed the cow but drink the cow’s milk, eat the cow when milk production ceases, then eat the wheat d. Feed the wheat to the cow and drink the milk e. Feed the wheat to the cow, drink the milk, then eat the cow f. Eat the wheat and then eat the cow