Presentation on theme: "Interactions of Living Things Guided Notes Food Chains, Food Webs, and the Transfer of Energy."— Presentation transcript:
Interactions of Living Things Guided Notes Food Chains, Food Webs, and the Transfer of Energy
GPS: S7L4 Students will examine the dependence of organisms on one another and their environments.
Ecology Ecology is the study of the interactions of living organisms with one another and their environment. An organisms environment consists of all the things that affect the organism. Biotic describes living factors in the environment. Abiotic describes the nonliving part of the environment, including water, rocks, light, and temperature.
5 Levels of Environmental Organization 1 st level – Individual organism any living thing 2 nd level – Population a group of organisms of the same species that live in a specific geographical area 3 rd level – Community all the populations of species that live in the same habitat and interact with each other
5 Levels of Environmental Organization 4 th level – Ecosystem a community of organisms and their abiotic environment, such as the rain forest or desert 5 th level – Biosphere the part of the Earth where life exists Includes any organism found in the air, land and water
Autotrophs A group of organisms that can make their own food by using energy from their surroundings Autotrophs are also called producers because they produce all of the food that heterotrophs use Without autotrophs, there would be no life on this planet Ex. Plants and Algae
Autotrophs Chemotrophs Autotrophs that get their energy from inorganic substances, such as salt Live deep down in the ocean where there is no sunlight Ex. Bacteria and Deep Sea Worms
Heterotrophs Organisms that cannot make their own food Another term for heterotroph is consumer because they need to consume other organisms to obtain energy and nutrients Ex. Rabbits, Deer, Mushrooms
Heterotrophs Consumers 1. Scavengers/Detritivores – feed on the tissue of dead organisms (both plants and animals) Ex. – Vultures, Crows, and Shrimp
Heterotrophs Consumers 4. Omnivores – eat BOTH plants and animals Ex. – Bears and Humans
Heterotrophs Consumers 5. Decomposers – absorb any dead material and break it down into simple nutrients or fertilizers Ex. – Bacteria and Mushrooms
GPS: S7L4b Students will explain that in a food web, sunlight is the source of energy and that this energy moves from organism to organism.
Transfer of Energy The energy in an organism that is eaten goes into the body of the organism that eats it No organism ever receives ALL of the energy from the organism it just ate. For example: When a zebra eats the grass, it does not obtain all of the energy the grass has (much of it is not eaten) When a lion eats a zebra, it does not get all of the energy from the zebra (much of it is lost as heat)
Trophic Levels Each step in this transfer of energy is known as a trophic level The main trophic levels are producers, consumers, and decomposers Only 10% of the energy from one trophic level is transferred to the next – this is called the 10% law
GPS: S7L4a Students will demonstrate that in a food web matter is transferred from one organism to another and can recycle between organisms and their environments.
Food Chains The energy flow from one trophic level to the next is known as a food chain A food chain is simple and direct It involves one organism at each trophic level Primary Consumers – eat autotrophs (producers) Secondary Consumers – eat the primary consumers Tertiary Consumers – eat the secondary consumers Decomposers – bacteria and fungi that break down dead organisms and recycle the material back into the environment
Food Web In most ecosystems, organisms eat more than one thing When more organisms are involved, it is known as a FOOD WEB – a system of many connected food chains in an ecosystem Food webs are more complex than food chains and involve lots of organisms
Food Web Notice the direction that the arrow points, the arrow points in the direction of the energy transfer, NOT what ate what
Ecological Pyramid (Energy Pyramid) An ecological pyramid shows the relationship between consumers and producers at different trophic levels in an ecosystem Shows the relative amounts of energy or matter contained at each trophic level The pyramid shows which level has the most energy and the highest number of organisms
GPS: S7L4d Students will categorize relationships between organisms that are competitive or mutually beneficial.
Types of Interactions There are four main ways that individuals and populations affect one another in an ecosystem: Competition Predator and prey Symbiosis Coevolution
Types of Interactions Competition happens when more than one individual or population tries to use the same resources, such as food, water, shelter, or sunlight Predator-prey interactions occur when one organism eats another to get energy The organism that is eaten is called the prey, and the organism that eats the prey is called the predator
Types of Interactions Symbiosis is a close and permanent association between organisms of different species Commensalism – a relationship in which one organism benefits and the other is not affected Example: Barnacles on a whale Mutualism – a relationship in which both organisms benefit from each other Example: Birds eating pest off a rhinos back Parasitism – A relationship in which one organism benefits and the other is harmed Example: Ticks on a dog
Types of Interactions Coevolution occurs when a long-term change happens in two species because of their close relationship Ex: The relationship between some flowers and the organisms that pollinate them. Flowers need to attract pollinators to help them reproduce. Different flowers have evolved different ways to attract pollinators; some use color or odors, while others use nectar as a food reward.
GPS: S7L4c Students will recognize that changes in environmental conditions can affect the survival of both individuals and entire species.
Ecological Succession A change in the community in which new populations of organisms gradually replace existing ones 1. Primary Succession – occurs in an area where there are no existing communities and for some reason (s) a new community of organisms move into the area
Ecological Succession A change in the community in which new populations of organisms gradually replace existing ones 2. Secondary Succession – occurs in an area where an existing community is partially damaged
Ecological Succession A change in the community in which new populations of organisms gradually replace existing ones 3. Climax Community – a community that is stable and has a great diversity of organisms
Guided Notes Review 1. Differentiate between autotrophs and heterotrophs. Identify the different types of heterotrophs. 2. Differentiate between a food chain and a food web. Describe how energy travels through a food chain/food web. 3. Describe the structure and organization of an ecological pyramid. 4. Identify and describe the 3 symbiotic relationships.