ECOSYSTEMS: COMPONENTS, ENERGY FLOW & MATTER CYCLING CHAPTER 4

ECOLOGY 4 Study of the relationships between organisms and their environment –How organisms interact with their nonliving environment such as sunlight, temperature, moisture, nutrients, etc. 4 KEY WORK IS: INTERACT - Connections in Nature

4 What is an organism? 4 What make up organisms?

Organisms are either: 4 EUCARYOTIC - –SURROUNDED BY A MEMBRANE –HAVE A DISTINCT NUCLEUS –HAVE INTERNAL ORGANELLES –All organisms except bacteria. 4 PROCARYOTIC - –SURROUNDED BY A MEMBRANE –NO DISTINCT NUCLEUS –NO INTERNAL PARTS SURROUNDED BY MEMBRANES –Bacteria

4 What is a SPECIES? 4 How do species differ? 4 What is the difference between sexual and asexual reproduction? 4 Number of species on earth is not known –5 million to 100 million maybe 4 Wild species - found in natural habitat 4 Domestic species - have been taken and therefore play a smaller role.

Population 4 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 4 Density = number of organisms/area 4 What is genetic diversity?

What is habitat? 4 Where an organism lives

What is a Community? 4 Populations of all species in a particular place at a particular time.

What is an Ecosystem? 4 Community of different species interacting with one another and with their nonliving environments. 4 Ecosystems can be small or large. 4 What is the Biosphere?

lithosphere hydrosphere Atmosphere Make up the Biosphere

What makes up the Atmosphere? 4 Troposphere miles up - contains our air. –What are the major gases that make up the air we breathe? 4 Stratosphere miles up - lowest portion contains the ozone layer –What is the purpose of the ozone layer?

What is the Hydrosphere? 4 Liquid water - surface and underground 4 Ice 4 Water vapor in the atmosphere

Interior of earth: 4 Core - mostly iron, some nickel –Center solid surrounded by a liquid core of molten material 4 Mantle - mainly iron with some Si, O,& Mg –Mostly solid rock except for asthenosphere which flows like plastic. 4 Crust - thinnest zone - 98% of it is only 8 elements

Life is sustained by: 4 One -way flow of energy - from sun through plants to animals - then back into space 4 Cycling of matter or nutrients 4 Gravity - allows planet to hold its atmosphere. 4 Earth is a closed system - receives energy from sun but loses no matter into space –Nutrients are recycled

4 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? 4 Lights & warms the planet 4 Supplies energy for photosynthesis 4 Powers cycling of matter 4 Drives the climate and weather systems

Facts about the sun 4 Middle- aged star 4 Takes 8 minutes for light to get to the earth 4 Most of light to earth is ultraviolet 4 About 28% of its light is reflected back into space by clouds, dust, and land 4 72% warms air and land, evaporates water, generates winds, 4 Only about.023% is used by plants for photosynthesis

Nutrient cycles 4 Nutrient - any atom, ion or molecule an organism needs to live 4 Macronutrients are needed in large amounts - CHONPS and a few others 4 Micronutrients - needed in small or trace amounts. 4 Also called Biogeochemical cycles. - life - earth - chemical cycles. –Driven by the sun –Main ones are hydrologic, nitrogen,carbon, phosphorus, and sulfur.

Ecosystem Concepts 4 Biomes - large regions characterized by climate and life-forms - especially vegetation 4 Climate - long term weather - mainly temperature and precipitation. 4 Aquatic life zones - freshwater & marine –Lakes & streams –Estuaries, coastlines, coral reefs, & deep ocean.

Ecosystem concepts 4 Ecotone - a region where two ecosystems meet. –Has more species diversity than either adjacent ecosystem. 4 Biotic - living components - plants and animals 4 Abiotic - nonliving components - water, nutrients, air, solar energy, etc.

Range of Tolerance 4 Ability to survive within variations of a physical or chemical environment –Individuals within a population may have differing ranges of tolerance 4 Tolerance limits - beyond which no member of a species is able to survive

Population Size LowHighTemperature Zone of intolerance Zone of physiological stress Optimum range Zone of physiological stress Zone of intolerance No organisms Few organisms Lower limit of tolerance Abundance of organisms Few organisms No organisms Upper limit of tolerance Range of Tolerance

Limiting Factors 4 Any one factor that is responsible for regulating population growth –Light, water –In aquatic ecosystems D.O. Sunlight Temperature

What is photosynthesis? 4 The producers (plants) also called autotrophs take carbon dioxide, water, and sunlight and produce glucose and oxygen. 4 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? 4 The feeding level of the organism.

4 Plants are 4 __________________ 4 They are the 4 __________________ in an ecosystem. 4 They occupy the 4 _______________ 4 Trophic level.

4 Cows are __________________ which are ________________ 4 Consumers. They occupy the ______________ 4 Trophic level.

4 Lions are 4 __________________ 4 They are 4 _____________ 4 Consumers. 4 They occupy the 4 ___________trophic level.

4 Pigs are _______ 4 Which means they eat 4 ______and ______;

4 Sharks are ______ 4 Which means they eat 4 __________

What are DETRITIVORES? 4 What are decomposers? 4 What are detritus feeders?

What is AEROBIC RESPIRATION? 4 Uses _____ + ______ and release _____,_______ ______, and _______

What is AEROBIC RESPIRATION? 4 Uses glucose + oxygen and release carbon dioxide, water, and energy. 4 All organisms carry on respiration!!!

What is Anaerobic Respiration? 4 Also called fermentation. 4 Does not use free oxygen 4 The end produces are compounds such as methane gas, ethyl alcohol, acetic acid, and hydrogen sulfide.