ECOSYSTEMS: COMPONENTS, ENERGY FLOW & MATTER CYCLING CHAPTER 4
ECOLOGY Study of the relationships between organisms and their environment How organisms interact with their nonliving environment such as sunlight, temperature, moisture, nutrients, etc. KEY WORK IS: INTERACT - Connections in Nature
What is an organism? What make up organisms? Cell - basic unit of life of all organisms
Organisms are either: EUCARYOTIC - PROCARYOTIC - SURROUNDED BY A MEMBRANE HAVE A DISTINCT NUCLEUS HAVE INTERNAL ORGANELLES All organisms except bacteria. PROCARYOTIC - SURROUNDED BY A MEMBRANE NO DISTINCT NUCLEUS NO INTERNAL PARTS SURROUNDED BY MEMBRANES Bacteria
What is the difference between sexual and asexual reproduction? What is a SPECIES? How do species differ? What is the difference between sexual and asexual reproduction? Number of species on earth is not known 5 million to 100 million maybe Wild species - found in natural habitat Domestic species - have been taken and therefore play a smaller role. Species - group of organisms that interbreed and produce fertile offspring Asexual reproduction - cell divides to produce two new cells, etc Sexual - combine sex cells or gametes (egg and sperm) and organism gets genetic material from both parents.
Population A group of organisms of the same species in a given area at a given time Can vary with: Season Time of day Time of year Density = number of organisms/area What is genetic diversity?
What is habitat? Where an organism lives
What is a Community? Populations of all species in a particular place at a particular time.
What is an Ecosystem? Community of different species interacting with one another and with their nonliving environments. Ecosystems can be small or large. What is the Biosphere?
lithosphere Atmosphere hydrosphere Make up the Biosphere
What makes up the Atmosphere? Troposphere - 0-11 miles up - contains our air. What are the major gases that make up the air we breathe? Stratosphere - 11-30 miles up - lowest portion contains the ozone layer What is the purpose of the ozone layer?
What is the Hydrosphere? Liquid water - surface and underground Ice Water vapor in the atmosphere
Interior of earth: Core - mostly iron, some nickel Center solid surrounded by a liquid core of molten material Mantle - mainly iron with some Si, O,& Mg Mostly solid rock except for asthenosphere which flows like plastic. Crust - thinnest zone - 98% of it is only 8 elements
Life is sustained by: One -way flow of energy - from sun through plants to animals - then back into space Cycling of matter or nutrients Gravity - allows planet to hold its atmosphere. Earth is a closed system - receives energy from sun but loses no matter into space Nutrients are recycled
Organisms are open systems - exchange matter and energy between the system and the environment. Take in matter and energy - use it to stay alive and put waste back into the environment.
How does the sun sustain life? Lights & warms the planet Supplies energy for photosynthesis Powers cycling of matter Drives the climate and weather systems
Facts about the sun Middle- aged star Takes 8 minutes for light to get to the earth Most of light to earth is ultraviolet About 28% of its light is reflected back into space by clouds, dust, and land 72% warms air and land, evaporates water, generates winds, Only about .023% is used by plants for photosynthesis
Nutrient cycles Nutrient - any atom, ion or molecule an organism needs to live Macronutrients are needed in large amounts - CHONPS and a few others Micronutrients - needed in small or trace amounts. Also called Biogeochemical cycles. - life - earth - chemical cycles. Driven by the sun Main ones are hydrologic, nitrogen,carbon, phosphorus, and sulfur.
Ecosystem Concepts Biomes - large regions characterized by climate and life-forms - especially vegetation Climate - long term weather - mainly temperature and precipitation. Aquatic life zones - freshwater & marine Lakes & streams Estuaries, coastlines, coral reefs, & deep ocean.
Ecosystem concepts Ecotone - a region where two ecosystems meet. Has more species diversity than either adjacent ecosystem. Biotic - living components - plants and animals Abiotic - nonliving components - water, nutrients, air, solar energy, etc.
Range of Tolerance Ability to survive within variations of a physical or chemical environment Individuals within a population may have differing ranges of tolerance Tolerance limits - beyond which no member of a species is able to survive
Abundance of organisms Range of Tolerance Population Size Low High Temperature Zone of intolerance physiological stress Optimum range No organisms Few Lower limit of tolerance Abundance of organisms Upper limit
Limiting Factors Any one factor that is responsible for regulating population growth Light, water In aquatic ecosystems D.O. Sunlight Temperature
What is photosynthesis? The producers (plants) also called autotrophs take carbon dioxide, water, and sunlight and produce glucose and oxygen. Chemosynthesis in the ocean uses heat energy from the thermal vents to convert dissolved hydrogen sulfide and carbon dioxide into organic nutrient molecules.
What is trophic level? The feeding level of the organism.
Plants are __________________ They are the __________________in an ecosystem. They occupy the _______________ Trophic level.
Cows are __________________ which are ________________ Consumers. They occupy the ______________ Trophic level.
Lions are __________________ They are _____________ Consumers. They occupy the ___________trophic level.
Pigs are _______ Which means they eat ______and ______;
Sharks are ______ Which means they eat __________
What are DETRITIVORES? What are decomposers? What are detritus feeders?
What is AEROBIC RESPIRATION? Uses _____ + ______ and release _____ ,_______ ______, and _______
What is AEROBIC RESPIRATION? Uses glucose + oxygen and release carbon dioxide, water, and energy. All organisms carry on respiration!!!
What is Anaerobic Respiration? Also called fermentation. Does not use free oxygen The end produces are compounds such as methane gas, ethyl alcohol, acetic acid, and hydrogen sulfide.