Unit 1: Ecology. The flow of energy through an ecosystem is one of the most important factors that determines the system’s capacity to sustain life.

Unit 1: EcologyUnit 1: Ecology

The flow of energy through The flow of energy through an ecosystem is one of the an ecosystem is one of the most important factors that most important factors that determines the system’s determines the system’s capacity to sustain life.capacity to sustain life.

Adenosine Triphosphate (ATP)Adenosine Triphosphate (ATP)

ATP :ATP : AdenineAdenine Ribose Ribose 3 phosphate groups 3 phosphate groups

– the bonds between – the bonds between the phosphates are the phosphates are where the energy is where the energy is stored – bonds must stored – bonds must be broken to release be broken to release the energythe energy

Reminder: ATP/ADP CycleReminder: ATP/ADP Cycle

Interactions and InterdependenceInteractions and Interdependence

EcologyEcology The study of interactions and The study of interactions and

relationships between organisms relationships between organisms and their environment.and their environment.

Interactions and InterdependenceInteractions and Interdependence

What non-living things in their environment What non-living things in their environment do organisms interact with?do organisms interact with? Sunlight, air, water, soil, rocksSunlight, air, water, soil, rocks

In what ways are these nonliving things In what ways are these nonliving things essential to organisms?essential to organisms? Photosynthesis, Oxygen in air, bacteria live in Photosynthesis, Oxygen in air, bacteria live in

soil, mosses on rocks, etc.soil, mosses on rocks, etc.

BiosphereBiosphere

Contains the combined portions of the Contains the combined portions of the planet in which all of life exists, including planet in which all of life exists, including land, water, and air (atmosphere)land, water, and air (atmosphere)

Levels of OrganizationLevels of Organization

ProducersProducers

Sunlight is the main energy source for life Sunlight is the main energy source for life on Earth.on Earth.

ProducersProducers Producers are also known as Producers are also known as autotrophsautotrophs

– they make their own food – they make their own food Two types:Two types:

Photo-autotrophs: use sunlight in process of Photo-autotrophs: use sunlight in process of photosynthesisphotosynthesis

Chemo-autotrophs: use inorganic chemicalsChemo-autotrophs: use inorganic chemicals

Producers -- Energy from the SunProducers -- Energy from the Sun

PhotosynthesisPhotosynthesis Using light energy to power chemical Using light energy to power chemical

reactions to turn Carbon Dioxide (COreactions to turn Carbon Dioxide (CO22) and ) and

water into Oxygen(Owater into Oxygen(O22) and sugars.) and sugars.

6CO6CO22 + 6H + 6H22O 6OO 6O22 + C + C66HH1212OO66

Light energy

Producers -- Energy from the SunProducers -- Energy from the Sun

On land, plants are the main On land, plants are the main autotrophs.autotrophs.

In freshwater ecosystems, algae In freshwater ecosystems, algae are the main autotrophsare the main autotrophs

Cellular RespirationCellular Respiration

Cellular respiration: Both Cellular respiration: Both autotrophs & heterotrophs autotrophs & heterotrophs perform this to release energy perform this to release energy from food to do cellular work.from food to do cellular work.

6O6O22 + C + C66HH1212OO6 6 --> 6CO--> 6CO22 + 6H + 6H22O O

Biochemical pathwaysBiochemical pathways

ConsumersConsumers

HeterotrophsHeterotrophs Consumers that rely on other organisms for Consumers that rely on other organisms for

their energy and food supply.their energy and food supply. Indirect use of sun’s energyIndirect use of sun’s energy

Consumers -- Heterotrophs Consumers -- Heterotrophs

Herbivores Herbivores — eat plants (rabbit)— eat plants (rabbit)

Carnivores Carnivores — eat other animals— eat other animals OmnivoresOmnivores — eat both plants and animals — eat both plants and animals DetritivoresDetritivores — feed on plant and animal — feed on plant and animal

remains called detritus.remains called detritus. DecomposersDecomposers — break down organic — break down organic

matter (bacteria and fungi).matter (bacteria and fungi).

Feeding RelationshipsFeeding Relationships

Energy flows through an ecosystem in Energy flows through an ecosystem in oneone direction:direction:

SunlightSunlightProducers Producers ConsumersConsumers

Energy TransformationsEnergy Transformations Only 10% of the energy at each Only 10% of the energy at each trophic leveltrophic level

is passed on to the next:is passed on to the next: Primary – 1Primary – 1stst

Secondary – 2Secondary – 2ndnd

Tertiary – 3Tertiary – 3rdrd

Quaternary – 4Quaternary – 4thth

The other 90% is lost as heat when The other 90% is lost as heat when consumers burn food during cellular consumers burn food during cellular respiration (this is good because it helps us to respiration (this is good because it helps us to maintain our body temperature!)maintain our body temperature!)

Trophic LevelsTrophic Levels

Food ChainFood Chain A series of steps in which organisms A series of steps in which organisms

transfer energy by eating and being transfer energy by eating and being eaten; travels in one direction.eaten; travels in one direction.

Always begins with producers who store Always begins with producers who store energy in the chemical bonds of the energy in the chemical bonds of the foods they make.foods they make.

Stored energy is passed on to Stored energy is passed on to consumers when they eat producers or consumers when they eat producers or other consumers.other consumers.

Feeding RelationshipsFeeding Relationships

Food WebFood Web A A networknetwork of feeding of feeding

relationships in an relationships in an ecosystemecosystem

Aquatic Food WebAquatic Food Web

Ecological PyramidsEcological Pyramids

A diagram that shows the relative amounts A diagram that shows the relative amounts of energy or matter contained within each of energy or matter contained within each trophic level in a food chain.trophic level in a food chain.

Energy PyramidEnergy Pyramid Biomass PyramidBiomass Pyramid Pyramid of NumbersPyramid of Numbers

Ecological PyramidsEcological Pyramids

Pyramid of NumbersShows the relative number of Individual organisms at eachtrophic level.

Biomass PyramidRepresents the amount ofliving organic matter at each trophic level. Typically, thegreatest biomass is at the base of the pyramid.

Energy PyramidShows the relative amount of energy available at each trophic level. Organisms use about 10 percent of this energy for life processes. The rest is lost as heat.

Recycling in the BiosphereRecycling in the Biosphere

Matter and energy move differently Matter and energy move differently through the ecosystem.through the ecosystem. Energy flows one way – some is lost as heat, Energy flows one way – some is lost as heat,

only 10% of energy is used directly by only 10% of energy is used directly by organisms at each trophic levelorganisms at each trophic level

Matter is RECYCLED through the ecosystemMatter is RECYCLED through the ecosystem• Law of Conservation of MatterLaw of Conservation of Matter• Matter can be transformed Matter can be transformed

Ecosystems, Communities, & Ecosystems, Communities, & Population Growth Population Growth

Factors in an EcosystemFactors in an Ecosystem

Biotic factors: living organisms with Biotic factors: living organisms with which an organism might interact.which an organism might interact.

Ex: insects, plants, etc. Ex: insects, plants, etc. Abiotic Factors: physical or nonliving Abiotic Factors: physical or nonliving

factors with which an organism might factors with which an organism might interact.interact.

Ex: sunlight, wind, soil, etc. Ex: sunlight, wind, soil, etc.

List the Biotic Factors in the pictureList the Biotic Factors in the picture

List the Abiotic factors in the pictureList the Abiotic factors in the picture

Community InteractionsCommunity Interactions

Competition occurs when organisms Competition occurs when organisms attempt to use an ecological resource in attempt to use an ecological resource in the the same place and at the same timesame place and at the same time..

Resource = any necessity of lifeResource = any necessity of life Examples: water, nutrients, light, food, Examples: water, nutrients, light, food,

spacespace

Community InteractionsCommunity Interactions

PredationPredation occurs occurs when one when one organism organism captures & feeds captures & feeds on another on another organismorganism

Ex: lions hunt Ex: lions hunt deerdeer

Community InteractionsCommunity Interactions

Symbiosis: 3 main typesSymbiosis: 3 main types MutualismMutualism = both organisms benefit from = both organisms benefit from

the relationshipthe relationship CommensalismCommensalism = one organism benefits = one organism benefits

while the other organism is neither helped while the other organism is neither helped nor harmednor harmed

ParasitismParasitism = one organism benefits at the = one organism benefits at the expense of the other organismexpense of the other organism

MutualismMutualism

Butterflies and flowers

CommensalismCommensalism

Barnacles on a Whale

ParasitismParasitism

HEARTWORMS

Ecological SuccessionEcological Succession Predictable changes that occur in a Predictable changes that occur in a

community over timecommunity over time Primary succession: occurs on surfaces Primary succession: occurs on surfaces

where no soil existswhere no soil exists Examples: after a volcanic explosion Examples: after a volcanic explosion

where the land is covered with lava or where the land is covered with lava or ashes or on bare rock exposed by glacier ashes or on bare rock exposed by glacier meltmelt

Pioneer species: first species to populate Pioneer species: first species to populate the area (often lichens)the area (often lichens)

Primary SuccessionPrimary Succession

Ecological SuccessionEcological Succession

Secondary succession: follows a Secondary succession: follows a disturbance that changes an disturbance that changes an existing community without existing community without removing the soilremoving the soil

Example: wildfires, plowing, Example: wildfires, plowing, logging industrylogging industry

Population GrowthPopulation Growth

Affected by 3 factors:Affected by 3 factors: # of births# of births # of deaths# of deaths # of organisms arriving or leaving: # of organisms arriving or leaving:

Immigration and emigrationImmigration and emigration

Exponential GrowthExponential Growth Exponential growth occurs when Exponential growth occurs when

organisms in a population reproduce at a organisms in a population reproduce at a constant rateconstant rate

Tends to happen when resources are Tends to happen when resources are unlimitedunlimited

Example – bacteriaExample – bacteria 2 split to become 42 split to become 4 4 split to become 84 split to become 8 8 split to become 16 and so it grows 8 split to become 16 and so it grows

on & onon & on

Exponential GrowthExponential Growth

Logistic GrowthLogistic Growth Happens when resources become less Happens when resources become less

available so growth will slow or stopavailable so growth will slow or stop Notice the patternNotice the pattern When does theWhen does the

growth slow & when growth slow & when

does it level out?does it level out?