CHAPTER 2 ECOSYSTEM a biological community of interacting organisms and their physical environment.
CONTENT STANDARD • 2.1 Energy Flow In Ecosystem • 2.2 Nutrient Cycle In The Ecosystem • 2.3 Interdependence And Interaction Among Organisms And, Between Organisms And The Environment. • 2.4 The Role Of Human In Maintaining A Balanced Nature
2.1 ENERGY FLOW IN ECOSYSTEM
Example : mushroom, bacteria, fungi
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FOOD CHAIN
Rat Snake Hawk Bacteria and fungi (decomposers) Paddy plants (producer) (primary consumer) (secondary consumer) (tertiary consumer) FOOD CHAIN A food chain can be used to show the feeding relationship between organisms.
WHAT IS A FOOD WEB? grass beatle grasshopper caterpillar bird eagle chicken A food web consists of several food chain that are interlinked.
FOOD WEB
USE THE LIST OF ORGANISMS BELOW TO FORM A FOOD WEB Paddy plant Grasshopper Bacteria and Rat Frog fungi Snake Bird Caterpillar Bacteria and fungi Paddy plant Rat Grasshopper Caterpillar Frog Bird Snake
ENERGY FLOW IN A FOOD WEB • as seen in the food chain, energy is also transferred from one organism to another organism in the food web. • some of energy is lost because it is used by the organism to move and carry out life process of respiration. • energy is also lost in the form of heat.
WATER CYCLE • The water cycle is the journey water takes as it moves from the land to the sky and back again. It follows a cycle of evaporation, condensation and precipitation. raining
CARBON CYCLE AND OXYGEN CYCLE • The process by which oxygen released into the atmosphere while the carbon dioxide released as a product of respiration is taken up for photosynthesis.
CARBON CYCLE
Role of organism in carbon and oxygen cycle • Decomposers, such as microbes and fungi, play an important role in the carbon cycle. • They break down the remains of dead plants and animals, release carbon dioxide through respiration. • During photosynthesis, plants give off oxygen and absorbs carbon dioxide.
STEPS TO SOLVE PROBLEMS WHEN THERE IS AN INTERFERENCE TO THE NUTRIENT CYCLE. Human activities that disrupt the nutrient cycle Steps to solve interferences to the nutrient cycle
2.3 INTERDEPENDENCE AMONG LIVING ORGANISMS
a species of water plant a species of fish A SPECIES OF FROG 1. Species is a group of organisms that have the same shape & structure （common characteristecs） and breed together. 2. In the figure above, fish, frog and water plant are three different species.
1. A population is a number or group of organisms of the same species that live together in a habitat. of fishes ApopulationApopulation of water plants Apopulation of frogs
1. A community is made up of many populations living together in a particular place. All the fishes, frogs, tadpoles, water plants, snails, grass and butterflies made up the pond community.
1. A habitat is a natural living place of certain plants and animals. 2. A habitat provides the needs of organisms to survive, such as :
It is a habitat for water lily.
It is a habitat for frog.
It is a habitat for water snail.
It is a habitat for water plant.
1.An ecosystem : interdependence (saling bersandaran) between community of organisms, with the non-living component/factor in the same habitat. 2. non-living component/factor such as water, light, soil and air. light air water soil
The interdependence between living components and non-living component creates a BALANCE ECOSYSTEM. HARMONY !! Without any external interference (gangguan）.
The distribution (pembahagian) of living things are affected by • Temperature • Humidity • Light
Adaptation of Living Things to the Environment All organisms need to adapt (menyesuaikan diri) to their habitat to be able to survive. Adaptation is a modification or change in the organism's body or behaviour that helps it to survive. 1. Tropical : rainfall and sunlight all year long. (Hot & humid) Eg : Elephant and hippopotamus Have less fur and stay in water to cool down their bodies.
1. Tropical : rainfall and sunlight all year long. Hot & humid) *Elephant : Have less fur to release heat easily. *Hippopotamus: stay in water to cool down their bodies. 2. Desert : ( Extreme hot & dry) *Camel : The hump stores food in the form of fat which is oxidised to produce water . *Cactus : Leaves are adapted into spikes to reduce water loss and the long roots grow deep into the soil to absorb water. Its stems have chlorophyll and are able to store water . 3. Tundra : Long winter short summer. (Very cold) *Polar bear : Has thick fur as heat insulator. *Seal: Has a layer of thick fat as heat insulator.
INTERACTION BETWEEN LIVING ORGANISMS
1. Prey-predator is a relationship where an animal captures and eat other animals. 2. A predator is an organism that kill and eats another organism. 3. A prey is the organism that is eaten.
4.FOR EXAMPLE, SNAKE IS A PREDATOR, RAT IS ITS PREY. PREDATOR PREY
5. OTHER EXAMPLES, Predator Prey
1. Symbiosis happen between two or more different species which live close together and interact with each other. There are three types of symbiosis: • Commensalism • Mutualism • Parasitism
A. Commensalism is a relationship between two organisms which only benefits one organism without harming the other.
-Remora fish is the commensal, it feeds on the scraps of food left by the shark. The shark is unharmed.
-The staghorn fern grows on a tree. This helps it easily obtain sunlight to process photosyntesis. -Examples of plants that live on tress to obtain sunlight are: (i) the money plant (ii) the pigeon orchid (iii) the bird’s nest fern