1. Food Chains By
Mrs. Mercado

2. What is a food chain?
A food chain is a model that shows how is passed, in the form of food, from one organism to another. The arrows between the organisms show the direction of energy flow. Every organism needs energy in order to live.
A food chain is the sequence of who eats whom in an ecosystem.
energy

3. The model can be represented in different ways with the arrows always pointing to the organism receiving the energy.

4. Models without pictures

5. Primary source of energy
Energy Source
The primary source of energy is the sun.
Plants get their energy from the sun.
sun
hawk
grass
grasshopper
snake
Primary source of energy
Producer
Primary Consumer
Tertiary Consumer
Secondary Consumer

6. Primary source of energy
Producers
Green plants are called producers because they make their own food inside themselves, using water and sunlight, in a process known as photosynthesis.
The primary source of food in a food chain are green plants. They provide energy to the primary consumers known as herbivores.
grass
hawk
sun
grasshopper
snake
Primary source of energy
Producer
Primary Consumer
Secondary Consumer
Tertiary Consumer

7. Primary source of energy
Primary Consumers
The next link in the chain are the herbivores. Herbivores are the primary consumers which only eat producers (plants).
Consume means “eat.” Animals are consumers because they get their energy by eating (consuming) food provided by plants or other animals. Consumers do not make their own food. There are different levels of consumers.
grasshopper
hawk
sun
grass
snake
Primary source of energy
Producer
Secondary Consumer
Primary Consumer
Secondary Consumer

8. Levels of Consumers Herbivores: eat only plants (producers).
Carnivores: eat meat, in other words, they eat other consumers (herbivores or carnivores).
Omnivores: eat both plants (producers) and meat (consumers).

9. Primary source of energy
Secondary Consumers
Carnivores are consumers who eat herbivores or other carnivores.
These consumers are also called predators because they eat other animals. The animals eaten by predators are called prey.
snake
hawk
sun
grass
grasshopper
Primary source of energy
Producer
Primary Consumer
Secondary Consumer
Tertiary Consumer

10. Primary source of energy
Tertiary Consumers
The predator eats the prey therefore, the prey gets eaten by the ___________.
Here, the grasshopper is the prey of the snake, and the snake is the prey of the____________.
predator
hawk
sun
grass
grasshopper
snake
Primary source of energy
Producer
Tertiary Consumer
Primary Consumer
Secondary Consumer
hawk

11. Importance of the balance in a food chain
All the organisms in the food chain depend on each other. This relationship is called interdependence.
When one part of the food chain is altered, it affects all the parts in some way and for a long time.
When the producer is ,all the consumers are . Click to see an example of this chain reaction.
reduced
reduced

12. Food Web vs. Food Chain
While food chains follow just one path of energy, food webs follow more than one, showing multiple relationships between organisms.

13. Food Web
FOOD WEBS show how plants and animals are connected in many ways to help them
all survive.

14. Answer the following questions or complete the sentences.
Every organism needs _____________ to live.
Where do plants get their energy from? 
The arrows point to the ______________ receiving the energy.
What is the primary source of energy?
Why are green plants called producers?
What is the primary source of food in a food chain?
What are the three levels of consumers mentioned in this presentation?
Why are the primary consumers called herbivores? 
Why are the secondary and tertiary consumers called carnivores?
What do omnivores eat?
What do producers use to make their own food?
The process in which plants make their own food is known as _______________.
The secondary and tertiary consumers are also known as predators because they _______________ other _______________. 
The _______________ gets eaten by the predator.
Mention the missing link in this food chain: Producer > _____________ > Carnivore
The relationship that all organisms in a food chain have is called _________________.
Food webs show ________________ relationships between __________________.

15. Activities Food web activity
Watch a movie about food chain.
Follow the activity instructions.
Select a habitat and complete the food chain.
Create a food chain
Food puzzle

16. Resources