The document discusses food chains, food webs, and food pyramids. It explains that in a food chain, energy passes from producers to consumers as herbivores eat plants, carnivores eat herbivores, and omnivores eat plants and other animals. A food web shows the interconnected food chains in an ecosystem. A food pyramid depicts the transfer of biomass and energy between trophic levels, with higher levels containing less biomass since most energy is lost as it moves up the chain.

1. FOOD WEB
AND FOOD
PYRAMID
SCIENCE 8

2. SIMPLE RECALL……..
What are the difference
between the food chain and
the food web?

3. Source: Google Images

4. Source: Google Images

5. Source: Google Images

7. ACTIVITY………..
Source: Google Images

8. -In order to live an animals it needs energy.
-Some animals get the energy they need to
live from eating plants and other
vegetation.
-Some animals get their energy from eating
other animals.
-Some animals eat both plants and other
animals.

9. Animals that eat plants are called Herbivores.
Herbivores have evolved to eat plants.
They have specialized teeth and stomachs to
enable them to get the energy they need from
plants.
Source: Google Images

10. Animals that eat meat are called Carnivores.
Carnivores have evolved to eat meat.
They have specialized teeth and stomachs to
enable them to get the energy they need from the
bodies of other animals.
Source: Google Images

11. Animals that eat plants and meat are called
Omnivores.
Humans are omnivores.
Omnivores have teeth and stomachs that enable
them to eat and digest both plants and meat.
Source: Google Images

12. Animals that are eaten by other animals are
called prey.
Some prey animals are herbivores.
Some omnivores and carnivores are also
prey to other animals.
Source: Google Images

13. Food webs show what eats what in order to
gain the energy it needs to live.
Food webs use arrows to show what eats
what.
Source: Google Images

14. Animals that eat other animals are called
predators.
Some animals are predators and prey.
This means they eat some animals but are
eaten by others.
The top predator that is prey to no other
animal is called an apex predator.

15. FOOD PYRAMID
When an organism eat, they take
in matter as well as the energy
into their bodies. The transfer of
matter expressed as biomass
and energy in food from one
trophic level to another are not
one hundred percent to use.

16. PYRAMID OF BIOMASS
- Food chains, pyramid of numbers and
pyramids of biomass are all ways
showing how energy is passed on from
one organism to another.
- Biomass, is the food available for the
next trophic level(feeding level) in the
food chain, it is also the source of
renewable energy to reduce our
dependence on fossil fuels.

17. PYRAMID OF BIOMASS
- More accurate indication of how much energy is passed
on at each trophic level
- Accordingly, biomass is the mass of living material in
each organism multiplied by the total number of
organisms in that trophic level
Source: Google Images

18. Biomass is the total mass
organisms in a food chain or
food web and the relationship
between the producers and
consumers can be best
illustrated through a biomass
pyramid and an energy pyramid

19. Source: Google Images

20. EXAMPLE……
Energy flow
The table below shows that for each 100kJ of energy
consumed by a cow, 63kJ is not absorbed into the cow and
only 4kJ is converted into new tissue.
Energy consumption by a cow
How much energy is used in respiration and given out as
heat?
Type Eaten Tissues Feces,
urine/
gas
Respiration
Amount 100kJ 4kJ 63kJ ?kJ

21. THINK/PAIR AND
SHARE

22. MINUTE QUIZ
In a ¼ sheet of paper. Answer the question
below.
Which is efficient in converting biomass of
producers to biomass of consumers- a
meat eater or a plant eater? Why?

23. ASSIGNMENT
In a one half crosswise kindly answer the
question.
Construct your own food pyramid. Kindly
label the components and the biomass you
want to include.

24. FOOD FOR INSPIRATION
“ Learning is a painful
process. We must cope
and accept the
challenge.”

25. THANK YOU FOR
LISTENING(: