Definitions [4]
A series of organisms where one is eaten by the next and energy flows from producers to consumers is called a food chain.
A network of interconnected food chains showing how various organisms are related through feeding relationships is called a food web.
Define the following term:
Photolysis of water
Releasing electrons and dividing the water molecule (H2O) into its two components (Hydrogen and Oxygen). Photolysis is the term used to describe this reaction, which is characterised by the fracturing of molecules by light (photo = light, lysis = breaking).
Photosynthesis is the process by which living plant cells, containing chlorophyll, produce food substances (glucose and starch) from carbon dioxide and water by using light energy. Plants release oxygen as a byproduct during photosynthesis.
Key Points
- A food chain is a linear sequence of organisms in which food energy is transferred from producers to consumers.
- Every food chain begins with producers (green plants) and usually ends with top consumers that are not preyed upon.
- Energy decreases at each trophic level, so food chains are usually short (not more than five levels).
- Shorter food chains are more stable and efficient, as less energy is lost at each step.
- A food web is a network of interconnected food chains operating within an ecosystem.
- It shows multiple feeding relationships, as organisms may have more than one food source.
- Food webs represent the flow of energy and nutrients among producers and consumers.
- The complexity of a food web depends on the diversity of organisms and the number of alternative food choices.
