KRISTINE JOAN DA. BARREDO
Learning Area Elementary Science
Level Grade 6, Intermediate
Learning Objectives Identify the kinds of relationship among living
Expected Outcomes * Classify the kind of relationship exists.
* Identify the relationship among living things based
on the given situation.
Science Process Skills observing, communicating, inferring, identifying
Keywords parasite, consumers, host. Predator, prey, mutualism,
commensalism, predation, parasitism
Author Kristine Joan DA. Barredo, Teacher II,
Tunasan Elementary School
Date June, 2011
Symbiosis- A close relationship between two
organisms where at least one organism
Types of symbiotic relationships
◦ Mutualism (both benefit)
◦ Commensalism (one benefits and one not affected
◦ Parasitism (one benefits and one is harmed)
Mutualism occurs when species interact in a mutually
The oxpecker gets food (ticks and insects disturbed in the grass) and a safe haven
from the rhinoceros, and the rhinoceros has parasites (ticks) removed.
Example of mutualism: cleaner shrimp and a grouper fish
Cleaner shrimp picks off parasites from the grouper’s mouth and
gills. Both benefit.
Mycorrhizal fungi (threads) covering aspen roots: fungi aid in water
and nutrient absorption by the aspen and the aspen provides sugars
and other food molecules to the fungi.
The remora attaches to a shark and rides to where the
shark makes a kill. The remora eats the left over
scraps of meat.
Commensalism: Barnacles and Grey Whales
Barnacles attach to the head of the whale and feed on plankton
where ever the whale swims. The barnacles don’t harm the
Vampire bats feed on the blood of
mammals without killing their host.
Parasites feed off other organisms called
Parasites usually don’t kill their host.
Ectoparasites- Live outside the host
◦ Example: ticks and humans
•ecological relationships in which
one organism (population, species)
benefits and the other is harmed
A predator is an animal that hunts
other animals for food. The animals
that are eaten are the prey.
Classify the following pictures
as to what type of
interrelationship exist among
◦Write PREDATION, MUTUALISM,
COMMENSALISM, or PARASITISM
In your worksheet.
ACTIVITY CARD #1
_____1. Eagles build their nests on treetops. The eagle are
protected by the thick foliage. The trees are not harmed or
benefited by the eagles.
_____2. Many other birds find food and shelter in the trees in
the forests. The birds help disperse the seeds of the seeds.
_____3. Monkeys climb or swing among the branches of trees.
The trees provide shelter to the monkeys. Hunters have a
difficult time catching them.
_____4. Bacteria and fungi feed on dead plants and animals.
They break the dead organisms into simple nutrients the
plants can use.
_____5. Cats are hunting mice in the corners of the house.
ACTIVITY CARD #2
Analyze the following
pictures. Identify what
exists in the living
Choose the letter of the correct answer
Read the questions carefully then choose the best
answer on the choices given below.
a. Aphids produce honeydew needed by
ants. In return, ants protect aphids from
b. The ants eat the aphids.
c. The aphids produces honeydew but the
ants do not give any help nor harm the
d. The aphids live on the ants habitat.
a. Mutualism mean that both members of a species
benefit from living together. Parasitism means that one
member of a species benefits without harming or
benefiting the member of another species.
b. Mutualism means that one member of a species
benefits without harming or benefiting the member of
another species. Parasitism means that both species'
members benefit from the relationship.
c. Mutualism means that one member of a species thrives
at the expense of the member of the species. Parasitism
means that one member of a species thrives at the
expense of the member of the species.
d. Mutualism means both members of a species benefit
from living together. Parasitism means that one
member of a species thrives at the expense of the
member of the species.
We Are Not Immune!
When it rains, most of
the chemicals sprayed
onto crops get washed
into rivers, and
eventually the sea.
Click to move on
Once a poisonous
chemical is in the
food chain, there is
a good chance that
humans will be
As a student, how will you decrease
the harmful contaminants in the
Jovero, Natividad V. (2009) Developing
Science Power, St. Mary’s Publishing
Corporation, Manila p. 35