Warm-Up #33

• Complete 3-1 Section Assessment #1-3 on page 65.

• Complete 3-2 Sections Assessment #1-5 on page 73.

The Biosphere

What is Ecology?

Objectives

• Identify the levels of organization that ecologists study.

• Describe the methods used to study ecology.

Ecology

• Ecology is the scientific study of interactions among organisms and between organisms and their environment.

• German biologist Ernst Haeckel based this term on the Greek work oikos, meaning house.

• Haeckel saw the living world as a household with an economy in which each organism plays a role.

Levels of Organization

Ecosystem

Community

Population

Individual

Biome

Biosphere

Organisms and Species

• the different forms of life on earth, can be classified into different species based on certain characteristics.

Fig. 3-3, p. 52

Insects751,000

Other animals281,000

Fungi69,000

Prokaryotes4,800

Plants248,400

Protists57,700

Known species1,412,000

Ecosystems

• Ecosystems are made up of not only the living organisms (biotic) but the non-living, or abiotic components as well.

• The biotic would be the plants, insects, birds, andhumans.

• The abiotic would be the soil, air, sunlight and water.

Ecological Methods

• Observing• Experimenting• Modeling—ecologists make models to gain

insight into complex phenomena such as the effects of global warming on ecosystems. – Many ecological models consist of mathematical

formulas based on data collected through observation and experimentation.

Summary

• What are the levels of organization that ecologists study?

• What methods do ecologists use?

The Biosphere

Energy Flow

Objectives

• Identify the source of energy for life processes.

• Trace the flow of energy through living systems.

• Evaluate the efficiency of energy transfer among organisms in an ecosystem.

Autotrophs

Organisms that use energy from the sun orenergy stored in chemical compounds to

manufacture their own nutrients

Producers

Heterotrophs

• Organisms that obtain nutrients from other organisms

Consumers

Heterotrophsthat onlyfeed onAutotrophs

Carnivores

Heterotrophs that only feed on other Heterotrophs

Scavengers

Omnivores

Heterotrophs that feed on both Autotrophs and Heterotrophs

Decomposers

Feeding Relationships

• Energy moves along a one-way path from sun or inorganic compounds to autotrophs (producers) and then to various heterotrophs (consumers).

• This flow of energy can be described using – Food chains—simple descriptions, not the most

accurate– Food Webs—more realistic description of energy

interactions.

Food Chains

Food chains simple track ofenergy flow throughecosystem

Grass

Pronghorn

Coyote

Producer

Autotroph Heterotroph

1st Order (Level) Consumer

2nd Order (Level) Consumer

Herbivore Carnivore

Heterotroph

3rd Order (Level)Consumer

Heterotroph

Carnivore

Food Webs

Food Webs offer a more realistic track of energy

flow through an ecosystem

Fig. 3-18, p. 65

HumansBlue whale Sperm whale

Crabeater seal Elephant seal

Killer whale

Leopard seal

Adelie penguins Emperor

penguin

Petrel FishSquid

Carnivorous plankton

Krill Herbivorous plankton

Phytoplankton

CheetahImpala Dung Beetle Vulture

Giraffe

Trees&

Grass Fungi

Wildebeest

Zebra

Hunting Dog

TermitesLion

Hyena

Identify the:

1. Producers

2. Primary (1st Level) Consumers

3. Secondary (2nd level) Consumers

4. Tertiary (3rd level) consumers

5. Herbivores

6. Carnivores

7. Omnivores

8. What elements are missing from this food web?

9. What is one food chain of the food web?

10. How would a toxin sprayed on the producers in which they can’t break it down and it stays in their tissues influence the other trophic levels?

Ecological Pyramids

• There are 3 basic types of ecological pyramids– Energy– Numbers– Biomass

Energy Pyramid Notice the change in the amount of energy that is available as you move up a trophic level

What pattern do you see?

It is referred to as the 10% rule

What happened to all the energy?

Again notice the pattern we saw earlier

Pyramid of Biomass

Size of boxes indicates the amount of biomass

Pyramid ofNumbers

• Shows relative number of individuals ateach trophiclevel.

Summary

• What is the source of energy for all life processes?

• How does energy flow through living systems?• What two ways to we use to describe this

energy flow?• What are the three types of energy pyramids?• How much energy is conserved from level to

level?

Homework

• Read Text 74-84• Complete Study Guide 104-105