1. FOOD
CHAINS
TROPHIC
LEVELS
ECOLOGICAL
PYRAMIDS

2. Keep in mind that the arrow tip always points towards the “eater”.
FOOD CHAINS
Food Chain:
is a sequence of feeding relationships describing ______
___________________.
which
organism eats another
The ____ is the ______________ for food chains.
Sun
source of energy
eagle
Keep in mind that the arrow tip always points towards the “eater”.
snake
eater
frog
grass-
hopper
grass
food

3. FOOD CHAINS Label and write descriptions on your food chain diagram.
There are different levels of consumers…..
eagle
Since they _______ make their own food,
cannot
they must
eat or “________” other organisms.
snake
consume
frog
They form the _____ of all ________ food chains.
basis
grass-
hopper
terrestrial
They use the energy in
_______ to make their
own food
sunlight
grass
through a process called _____________.
photosynthesis

4. FOOD CHAINS Top carnivore:
any organism that is __________ by any other.
not hunted
It’s at the ___ of its food chain.
top
There are different levels of consumers…..
eagle
quaternary consumer
The ___ consumer in a food chain. It eats ________________.
4th
tertiary consumers
snake
tertiary consumer
The ___ consumer in a food chain. It eats __________________.
3rd
secondary consumers
frog
secondary consumer
The ___ consumer in a food chain. It eats ________________.
2nd
primary consumers
grass-
hopper
primary consumer
The ___ consumer in a food chain. It eats _________.
1st
producers
grass

5. Let’s THINK

6. FOOD CHAINS All organisms eventually die and decompose. eagle
is the ___________ and _____________ of dead organisms.
Detritus:
waste matter
rotting remains
snake
Decomposers:
are organisms that ___
_______ and break it down into ________.
frog
detritus
eat
detritus
grass-
hopper
nutrients
decomposers
grass
are substances
needed for an organism’s
______ and _____.
Nutrients:
The cycle restarts.
nutrients
growth
repair

7. Let’s THINK

8. HUMANS AND FOOD CHAINS
Since humans are not hunted for food by any other animal,
and since humans eat almost anything,
(well maybe not this)
this makes us
____________.
top carnivores ?
Where are humans on any food chain?
Count how many of these animals you’ve eaten in your life.

9. What food chains did you participate in when you ate this?
HUMANS AND FOOD CHAINS
Have you ever eaten one of these?
What food chains did you participate in when you ate this?
What is it made of?
wheat
beef
tomato
cheese
onion
lettuce

10. HUMANS AND FOOD CHAINS human human human human human
Humans are mainly _______ consumers because we eat a lot of _____.
primary
cow
When we eat animals, they are usually _________ ,
plants
so this makes us also _________ consumers.
herbivores
secondary
wheat
lettuce
onion
tomato
grass

11. FOOD WEBS No ecosystem is only made up of only one food chain.
Members of one food chain usually also belong to another.
When you put all the _____________ food chains in an ecosystem together, you form a ________.
interconnecting
food web

12. TROPHIC LEVELS Trophic Level:
It is the _______ an organism occupies in a food chain.
position
Each ___ in the chain represents one trophic level.
link
grass
grass-
hopper
frog
snake
eagle
phytoplankton
zooplankton
small fish
larger fish
shark
On land, the first trophic level begins with ______.
plants
In the water, the first trophic level begins with _____________.
phytoplankton

13. TROPHIC LEVELS Trophic Level:
It is the _______ an organism occupies in a food chain.
position
Each ___ in the chain represents one trophic level.
link
grass
grass-
hopper
frog
snake
eagle
phytoplankton
zooplankton
small fish
larger fish
shark
5th trophic level
4th trophic level
3rd trophic level
2nd trophic level
1st trophic level

14. TROPHIC LEVELS
As organisms eat one another, ______ is transferred up the food chain.
energy
eagle
0.1 kcal
However, as energy is moved from one trophic level to the next, only ___ % of the energy makes it to the next level.
- 0.9 kcal 10
snake
1 kcal
- 9 kcal
This 10 % is used to build _______
biomass
frog
10 kcal
as well as to fuel ______________.
bodily functions
- 90 kcal
This means that ___% of the energy is lost, 90
grass-
hopper
100 kcal
mostly in the form of _______
detritus
heat
- 900 kcal
and as ____ from metabolic processes.
grass
1000 kcal

15. ECOLOGICAL PYRAMIDS Ecological Pyramids:
These are diagrams that represent each
trophic level according to its ______ , _______ or _________.
energy
biomass
population
Total energy, from the Producers,
present in tertiary
consumers.
1) Pyramid of Energy:
This pyramid indicates the amount of ______ that is present in each trophic level.
energy
Total energy,
from the producers,
in secondary consumers.
The amount of energy always _________ as you move up trophic levels.
Total energy, from the producers, present in primary consumers.
decreases
Total energy present in producers.

16. ECOLOGICAL PYRAMIDS Ecological Pyramids:
These are diagrams that represent each
trophic level according to its ______ , _______ or _________.
energy
biomass
population
1) Pyramid of Energy:
This pyramid indicates the amount of ______ that is present in each trophic level.
energy
The amount of energy always _________ as you move up trophic levels.
decreases

17. ECOLOGICAL PYRAMIDS Ecological Pyramids:
These are diagrams that represent each
trophic level according to its ______ , _______ or _________.
energy
biomass
population
2) Pyramid of Biomass:
Total biomass
present in
tertiary
consumers.
This pyramid indicates the amount of _______ that is present in each trophic level, in a given area.
biomass
Total biomass
present in
secondary consumers.
Biomass is the amount of
_________ (without water) within organisms.
dry matter
Total biomass present in primary consumers.
On land, the amount of biomass _________ as you move up trophic levels.
decreases
Total biomass present in producers.

18. The End!