Food Webs

Energy flows through an ecosystem as one animal eats another animal or plant. This is a food chain and shows who eats who in an ecosystem. For example: A hawk -- eats a mouse who...(Read more...)
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National Science Standards for Food Webs

K-LS1-1. Use observations to describe patterns of what plants and animals (including humans) need to survive. [Clarification Statement: Examples of patterns could include that animals need to take in food but plants do not; the different kinds of food needed by different types of animals; the requirement of plants to have light; and, that all living things need water.]

Patterns
• Patterns in the natural and human designed world can be observed and used as evidence. (K-LS1-1)

 LS1.C: Organization for Matter and Energy Flow in Organisms
• All animals need food in order to live and grow. They obtain their food from plants or from other animals. Plants need water and light to live and grow. (K-LS1-1)

5-LS1 From Molecules to Organisms: Structures and Processes

5-LS1-1. Support an argument that plants get the materials they need for growth chiefly from air and water. [Clarification Statement: Emphasis is on the idea that plant matter comes mostly from air and water, not from the soil.]

LS1.C: Organization for Matter and Energy Flow in Organisms
• Plants acquire their material for growth chiefly from air and water. (5-LS1-1)

Energy and Matter
• Matter is transported into, out of, and within systems. (5-LS1-1)

5-LS2 Ecosystems: Interactions, Energy, and Dynamics

5-LS2-1.    Develop a model to describe the movement of matter among plants, animals, decomposers, and the environment. [Clarifcation Statement: Emphasis is on the idea that matter that is not food (air, water, decomposed materials in soil) is changed by plants into matter that is food. Examples of systems could include organisms, ecosystems, and the Earth.] [Assessment Boundary: Assessment does not include molecular explanations.]

LS2.A: Interdependent Relationships in Ecosystems
•The food of almost any kind of animal can be traced back to plants. Organisms are related in food webs in which some animals eat plants for food and other animals eat the animals that eat plants. Some organisms, such as fungi and bacteria, break down dead organisms (both plants or plants parts and animals) and therefore operate as “decomposers.” Decomposition eventually restores (recycles) some materials back to the soil. Organisms can survive only in environments in which their particular needs are met. A healthy ecosystem is one in which multiple species of different types are each able to meet their needs in a relatively stable web of life. Newly introduced species can damage the balance of an ecosystem. (5-LS2-1)

LS2.B: Cycles of Matter and Energy Transfer in Ecosystems
• Matter cycles between the air and soil and among plants, animals, and microbes as these organisms live and die. Organisms obtain gases, and water, from the environment, and release waste matter (gas, liquid, or solid) back into the environment. (5-LS2-1)