Chapter 3 “Biosphere”Chapter 3

“Biosphere”

3-1 What is Ecology?3-1 What is Ecology?

Ecology - study of how the living and nonliving world interacts.

Organisms and their environment

Biosphere – portions of the planet where all life exists

(land, water, and air)

Biological OrganizationBiological Organization

Individual – a single organism of a species

Population – group of individuals of the same species living together in a specific area

Biological OrganizationBiological Organization

Community – different populations living together in a specific area

Ecosystem - collection of all nonliving and living organisms living in a specific place

Biological OrganizationBiological OrganizationBiome – group of ecosystems that have similar climates and communities

Biosphere - portions of the planet where all life exists

(land, water, and air)

Methods of studyMethods of studyObservation – using the 5 senses and recording our findings

Experimentation testing the hypothesis; done in natural or unnatural (labs) environments

Modeling – done when the event or object being studies is too large or too far from us.

Section 3-1 AssessmentSection 3-1 Assessment1. List the six

different levels of organization ecologists use to study the environment.

2. Describe the three basic methods of ecological research

3-2 Energy Flow3-2 Energy FlowThe main energy source for life on Earth is the sun. How do you and I use the sun’s energy?

Those organisms that directly use the sun’s light to produce their own food are called Autotrophs.

Producers – another name for autotrophs on Earth

Energy FlowEnergy FlowNot all autotrophs

use the sun’s energy. Some rely on other inorganic chemical compounds.

Those organisms that do get their energy from the sun carry out a common process to use light energy to carry out chemical rxns.

These are called “chemoautotrophs”

PhotosynthesisPhotosynthesisChemical rxn that converts carbon dioxide and water into oxygen and sugars

6CO2 + 6H2O C6H12O6 + 6O2

carbon water light sugar oxygen

dioxide energy

ChemosynthesisChemosynthesis

Process used by some autotrophs, they use chemical energy to produce carbohydratesSimilar to photosynthesis

ConsumersConsumersCannot harness energy directly from the environment as autotrophs do, instead they acquire energy from other organisms.

Heterotrophs – organisms that rely on other organisms for their energy and food supply

Types of ConsumersTypes of ConsumersHerbivores – obtain energy by eating only plants (cattle)

Omnivores – obtain energy by eating both plant and animals (humans)

Carnivores – obtain energy by eating other animals / meat (wolves)

Types of ConsumersTypes of Consumers

Detritivores – feed on plant and animal remains and other dead matter (earthworms)

Decomposers – break down organic matter (bacteria)

Levels of ConsumersLevels of ConsumersTrophic Level: A step in a food chain or food web

Tertiary: These individuals feed on secondary consumers; carnivores

Primary Consumer: These individuals feed on producers; herbivores

Secondary Consumer: These individuals feed on primary consumers; carnivores

Feeding RelationshipsFeeding RelationshipsEnergy flows through an ecosystem in one direction, it is not a cycle. It begins with the sun, then producers, and on to the consumers.

A diagram showing a single pathway of how energy travels through the ecosystem is called a food chain.

A diagram showing multiple pathways of how energy travels through the ecosystem is called a food web.

Ecological PyramidsEcological PyramidsShows the relative amounts of matter in each trophic level in the food chain / web

Energy Pyramid – only 10% of the energy stored in one trophic level is passed on to the next level; the remaining 90% is used or lost as heat.

Ecological PyramidsEcological PyramidsBiomass Pyramid – shows the total amount of living tissue

within a given trophic level; represents the amount of potential food available for each trophic level.

Numbers Pyramid – based on the number of individual organisms at each trophic level; shape is not always a pyramid

3-2 Section Review3-2 Section Review1. What is the main form of energy that

powers living things?

2. Briefly describe the flow of energy among organisms in an ecosystem.

3. What proportion of energy is transferred from one trophic level to the next?

3-3 Cycles3-3 CyclesUnlike energy, matter is recycled within the ecosystem

Biogeochemical cycles – show how elements, chemicals, and other forms of matter are passed from from one organism to another in the ecosystem.Connects biological, geological, and chemical aspects of the biosphere

Water cycleWater cycleEvaporation – process by which water changes from liquid to gas form

Transpiration – process by water evaporates from the leaves of plants

Condensation – process by which water changes from gas to liquid form

Water cycleWater cycleWhen it rains, snows, etc. (precipitation) the water will…Runoff to ponds/lakesSoak in and become

GroundwaterTaken up by roots and transpire

Evaporate

Nutrient cyclesNutrient cyclesCarbon

Nitrogen

Nutrient LimitationNutrient Limitation

Primary productivity

Limiting agent