1. Autotrophs Vs Heterotrophs

2. Notes
Student Outcome
To understand the flow of energy between organisms and how nutrients are obtained by different systems.
Text correspondence
Chapter 6 & 7 Heinemann Biology 1, 4th Edition

3. Where does all the energy in an ecosystem come from?
Source of Energy
Where does all the energy in an ecosystem come from?

4. Source of Energy
SUNLIGHT is the major source of energy for life on Earth.
What about deep sea ecosystems? Where is their energy coming from?

5. Source of Energy
In a few ecosystems, energy is stored in inorganic compounds.
Organisms break down these compounds, releasing the energy from their chemical bonds.

6. Producers
PRODUCERS are organisms that can capture the energy from sunlight or chemicals and use that energy to produce food.
They convert inorganic compounds to organic compounds.

7. Producers Producers are AUTOTROPHS
Autotrophs are organisms that are able to make their own food using the energy in sunlight or chemicals.
They do via the process known as photosynthesis

8. Autotrophs Autotrophs make their food in one of two ways:
PHOTOSYNTHESIS: use solar energy to power chemical reactions that turn carbon dioxide and water into oxygen and carbohydrates

9. Autotrophs Autotrophs make their food in one of two ways:
CHEMOSYNTHESIS: the process of using chemical energy stored in inorganic compounds to make carbohydrates

10. Many producers adapt to their environment

11. Producers
Since producers/autotrophs are the only organisms that can make their own food, how can the rest of us get energy?

12. Heterotrophs
Organisms that cannot harness energy directly from the physical environment are called HETEROTROPHS.
Heterotrophs have to get their energy from other organisms.

13. Consumers
Because heterotrophs have to consume/eat other living things to get their energy, they are also called CONSUMERS.

14. Types of heterotrophs Heterotroph What it eats Herbivore Carnivore
Omnivore
Detrivore
Decomposer

15. Energy Flow
Energy flows through an ecosystem in ONE DIRECTION ONLY- from the sun or inorganic compounds to autotrophs (producers) and then to various heterotrophs (consumers)

16. Food Chains
We can use our knowledge of energy flow in an ecosystem to create food chains.
A food chain is a series of steps in which organisms transfer energy by eating and being eaten.