Chapter 3: The Biosphere

Chapter 3: The Biosphere

Section 3-2: Energy Flow

Section 3-2: Energy Flow

Pass It AlongPass It Along• Energy flows in one direction through an

ecosystem, from the sun or inorganic compounds to producers (organisms that can make their own food) through various levels to consumers (organisms that rely on other organisms for food).

• Your body gets the energy and materials it needs for growth and repair from the foods you eat.

• Energy flows in one direction through an ecosystem, from the sun or inorganic compounds to producers (organisms that can make their own food) through various levels to consumers (organisms that rely on other organisms for food).

• Your body gets the energy and materials it needs for growth and repair from the foods you eat.

Section 3-2

Interest Grabber

The need for energy…The need for energy…

• Energy is needed to drive life processes

• Example: Ants can lift many times their mass - energy is needed!

• You need energy to wake up!• Ecosystems need energy to sustain

life.

• Energy is needed to drive life processes

• Example: Ants can lift many times their mass - energy is needed!

• You need energy to wake up!• Ecosystems need energy to sustain

life.

A. ProducersA. Producers

Sunlight is the main energy source for life

on Earth.

Sunlight is the main energy source for life

on Earth.

What were examples of producers associated with

the food web game?

What were examples of producers associated with

the food web game?

A.1:Energy From the Sun A.1:Energy From the Sun

• Photosynthesis: Plants harvesting energy from the sun

• Convert CO2 & H2O into Carbohydrates & water (Ch 8)

• Photosynthesis: Plants harvesting energy from the sun

• Convert CO2 & H2O into Carbohydrates & water (Ch 8)

Photosynthetic OrganismsPhotosynthetic Organisms

• Land– Plants are the

primary photosynthetic organisms

• Land– Plants are the

primary photosynthetic organisms

• Water– Algae or

phytoplankton are the main photosynthetic organisms

– Some photosynthetic bacteria as well

• Water– Algae or

phytoplankton are the main photosynthetic organisms

– Some photosynthetic bacteria as well

Photosynthetic Bacteria Photosynthetic Bacteria • Photosynthetic

bacteria like these are found in tidal flats and salt marshes

• They are called cynobacteria and contribute to the oxygen on the earth

• Photosynthetic bacteria like these are found in tidal flats and salt marshes

• They are called cynobacteria and contribute to the oxygen on the earth

A-2:Life Without Light: Chemosynthesis

A-2:Life Without Light: Chemosynthesis

• Chemosynthetic bacteria such as these use sulfur in hydrogen sulfide to produce energy rich carbohydrates

• Chemosynthetic bacteria such as these use sulfur in hydrogen sulfide to produce energy rich carbohydrates

Chemosynthetic BacteriaChemosynthetic Bacteria

• These bacteria live in remote places on the earth

• Yellowstone National Park’s hot springs is one such place

• Tidal marshes are another

• These bacteria live in remote places on the earth

• Yellowstone National Park’s hot springs is one such place

• Tidal marshes are another

Comparison of Photosynthesis & Chemosynthesis

Comparison of Photosynthesis & Chemosynthesis

B. ConsumersB. Consumers

Heterotrophs: Obtaining energy from

producers

Heterotrophs: Obtaining energy from

producers

HeterotrophsHeterotrophs

• Organisms that rely on other organisms for energy needs

• Also called consumers

• Organisms that rely on other organisms for energy needs

• Also called consumers

What were the heterotrophs associated

the food web game?

What were the heterotrophs associated

the food web game?

Types of HeterotrophsTypes of Heterotrophs

•1. Herbivores•2. Carnivores•3. Detritivores•4. Decomposers

•1. Herbivores•2. Carnivores•3. Detritivores•4. Decomposers

1. Herbivores1. Herbivores

• Eat plant material

• Examples?

• Eat plant material

• Examples?

2. Carnivores2. Carnivores

• Organisms that eat animals

• Examples?

• Organisms that eat animals

• Examples?

3. Omnivores3. Omnivores

• Organisms that eat both plants and animals

• Examples?

• Organisms that eat both plants and animals

• Examples?

4. Detritivores4. Detritivores

• Organisms that feed on plant & animal remains

• They eat dead matter - detritus!

• Examples?

• Organisms that feed on plant & animal remains

• They eat dead matter - detritus!

• Examples?

C. Feeding Relationships

C. Feeding Relationships

Movement of energy through

an ecosystem

Movement of energy through

an ecosystem

Energy FlowEnergy Flow

• Food - be it plant or animal food - contains energy

• Some food contains more energy than others

• Energy flows in one direction in an ecosystem

• Food - be it plant or animal food - contains energy

• Some food contains more energy than others

• Energy flows in one direction in an ecosystem

Energy FlowEnergy Flow

Energy flow…..!Energy flow…..!

C-1:Food Chains

C-1:Food Chains

• Energy is passed along in an ecosystem through food chains

• Food chain is a series of steps in which organisms pass energy in the form of food

• Energy is passed along in an ecosystem through food chains

• Food chain is a series of steps in which organisms pass energy in the form of food

Aquatic Food ChainsAquatic Food Chains

• Algae/phytoplankton are the basis for the aquatic systems.

• Algae/phytoplankton are the basis for the aquatic systems.

Pollution: Disruption in Aquatic Food Chains

Pollution: Disruption in Aquatic Food Chains

Biomagnification

C-2: Food WebsC-2: Food Webs

• Complex feeding relationships

• Feeding relationships can be quite confusing!

• This is a Great Lakes food web!

• Complex feeding relationships

• Feeding relationships can be quite confusing!

• This is a Great Lakes food web!

C-3: Trophic LevelsC-3: Trophic Levels

• Each step in a food chain is called a trophic level

• Produces make up the first level

• Consumers make up the 2nd, 3rd etc

• Each consumer depends on the trophic level below

• Each step in a food chain is called a trophic level

• Produces make up the first level

• Consumers make up the 2nd, 3rd etc

• Each consumer depends on the trophic level below

D. Ecological Pyramids

D. Ecological Pyramids

Representing Energy or the amount of

Matter or Numbers in an Ecosystem

3 Types of Pyramids

Representing Energy or the amount of

Matter or Numbers in an Ecosystem

3 Types of Pyramids

Pyramid of NumbersShows the relativenumber of individualorganisms 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.

Section 3-2

Ecological Pyramids

D-1: Energy PyramidD-1: Energy Pyramid• Energy is passed

between trophic levels

• Organisms use the energy for life functions

• Some of the energy is released as heat

• 10% is passed on to each successive trophic level

• Energy is passed between trophic levels

• Organisms use the energy for life functions

• Some of the energy is released as heat

• 10% is passed on to each successive trophic level

D-2: Biomass PyramidD-2: Biomass Pyramid

• Represents the amount of biomass at each trophic level

• Expressed in grams / unit area

• Represents the amount of biomass at each trophic level

• Expressed in grams / unit area

Biomass Pyramid EnlargedBiomass Pyramid Enlarged

Notice the change in grams @ each successive stage

D-3: Pyramid of Numbers

D-3: Pyramid of Numbers

• Represents the number of each organism at each trophic level

• May be the same or different than an energy of biomass pyramid

• Represents the number of each organism at each trophic level

• May be the same or different than an energy of biomass pyramid