List

Explain through examples the interactions between living organism

Justify the importance of interaction between living organism and the environment

Explain through examples the advantages and disadvantages of biological control in regulating the number of pests in certain area.

Learning outcomes

INTERACTION BETWEEN ORGANISM

COMPETITIONCOMPETITION SYMBIOSISSYMBIOSIS

COMMENSALISMCOMMENSALISM MUTUALISMMUTUALISM PARASITISMPARASITISM

A prey is the organism that is eaten.

A predator is an organism that kills eat and eat another organism.

Prey-predator is a relationship where an animal capture and eats other animal.

PREY-PREDATOR

Characteristics of Predator = sharp claws and fang

or sharp beak Prey = has ability to run away

Example: owl is predator, rat is its prey.

PREDATOR PREY

Competition occurs when organism compete for basic resources.

Plants compete to obtain water, minerals, sunlight and living place.

Animals compete to obtain water, food, living space and mate for reproduction.

COMPETITION

COMPETITION

INTER-SPECIFIC COMPETITION

INTRA-SPECIFIC COMPETITION

Two or more different species which live close together and interact with each other.

There are 3 type of symbiosis

1. Commensalism

2. Parasitism

3. Mutualism

SYMBIOSIS

A relationship between 2 organisms in which one organism (the commensal) benefit while the other(the host) does not receive any benefit or harm.

COMMENSALISM

COMMENSAL HOST

Example: a remora fish often found attach under a shark, get free transport and feeds on food scraps left by the shark.

An interaction between 2 different species of organism which benefits both organism.

MUTUALISM

This relationship helps both organism survive in harsh condition. Neither organism will be able to survive on its own.

They obtain nutrition and shelter from each other.

•Lichen consist of fungi and algae living together•The algae produce food and the fungi provide shelter

EXAMPLE OF MUTUALSIM

A sea anemone protect the clown fish from predators and provides it with food scraps

The clown fish draws larger fish into the tentacle of the sea anemone.

Parasite benefit by living in or outside the host.

The host is harmed or maybe killed by the parasites.

PARASITISM

PARASITE HOST

EXAMPLE:1.Mosquitoes (parasite) live on the skin of mammals (host) and suck the blood of the host.2.Tapeworm (parasite) lives in human intestine (host). Tapeworm obtains food and shelter. The host losing nutrient to the parasite and lose weight, become weaker.

RAFFLESIA

In any ecosystem, when a population grows too large , organism of the same species will compete with each other for their basic needs.

Some will die and this reduce the size of population.

The importance of interaction between organisms

A method in which a predator is used to control the population of the pest in an area.

Usually used in agriculture to control population of pest without the used of pesticides.

BIOLOGICAL CONTROL

Example

1. It does not pollute the environment

2. It does not kill other organisms other than the pests because natural enemies of the pests are used.

3. It is cheap and safe to use.

Advantages of biological control

In malaysia, an increase number of crow has posed a problem to people in Klang.

Crows used to control the hawk moth. With food scraps available in Klang, the crow population increased.

Disadvantages of biological control

EXERCISES

QUESTION 1

The following are interactions between living things except

A competitionB parasitismC prey - predatorD photosynthesis

Owls and snakes are reared in oil palm plantations to

A help produce carbon dioxide

for the photosynthesis of the oil palm plants

B control the population of pestsC reduce grass and weedsD help pollination

QUESTION 2

3. What is relationship in which

a) one organism has benefited and the other is harmed? PARASITISM

b) both organisms have benefited?

MUTUALISM

c) one organism has benefited and the other is unharmed?

COMMENSALISM

LET’S DO EXERCISE

SCIENCE PROCESS SKILL’S BOOK

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