(5-8) B5

Science Curriculum Preview Committee Clarification of Learning Results

Revised 04/08/04

5-8

B5: Describe various mechanisms found in the natural world for transporting living and nonliving matter and the results of such movements.

Curriculum Organizing Questions

Where does the water in our drinking fountain come from?

What would the earth be like without decomposers?

How does the statement "you are what you eat" relate to ecosystems?

Where do the parts that made this organism come from?

How are coal and oil formed?

Elaboration
This standard encompasses the water cycle, rock cycle, and carbon cycles and the idea of global food webs. The water cycle should be simplified and students should not be expected to understand how clouds form or the details of precipitation. Knowledge of the rock cycle in its entirety is not necessary to meet this standard, but students need to understand that rock (e.g., limestone, coal) and oil are important carbon sinks. Students should also understand the importance of photosynthesis and respiration as material cycling processes. An understanding of nitrogen fixation is not necessary at this point, but a clear understanding of the role of decay is.

Specific Ideas

Water evaporates from the surface of the earth, rises and cools, condenses into rain or snow, and falls again to the surface.Benchmarks 4B7

The water falling on land collects in rivers and lakes, soil and porous layers of rock, and much of it flows back into the ocean.Benchmarks 4B7

Plants alter the earth's atmosphere by removing carbon dioxide from it, using the carbon to make sugars, and releasing oxygen. This process is responsible for the oxygen content of the air.SFAA p. 46

All organisms are part of and depend on two main interconnected global food webs. One includes microscopic ocean plants, the animals that feed on them, and finally the animals that feed on those animals. The other web includes land plants, the animals that feed on them, and so forth. The cycles continue indefinitely because organisms decompose after death to return food material to the environment. Benchmarks 5A5

Over a long time, matter is transferred from one organism to another repeatedly, and between organisms and their physical environment. As in all material systems, the total amount of matter remains constant, even though its form and location change.Benchmarks 5E2

Food provides molecules that serve as fuel and building material for all organisms.Benchmarks 5E1

Plants use the energy in light to make sugars out of carbon dioxide and water.Benchmarks 5E1

Organisms that eat plants break down the plant structures to produce the materials and energy they need to survive. Then they are consumed by other organisms.Benchmarks 5E1

Developmental & Instructional Implications
Some middle school students think dead organisms rot away. They do not realize that the matter from the dead organism is converted into other materials in the environment. Some students think that environmental processes involve destruction and creation of matter, rather than the transformation of one substance to another. Other students may recognize one form of recycling through soil materials but fail to incorporate water, oxygen, and carbon dioxide into matter cycles. Even after specially designed instruction students cling to their misinterpretations. Instruction that traces matter through the ecosystem as a basic pattern of thinking may help correct these difficulties.Benchmarks p.343

The school science definition of food, as organic compounds which organisms can use as a source of energy for metabolic processes, is not consistently used even by science educators. Moreover, the word "food" , when used in science lessons, is used in a variety of ways both by teachers and in textbooks. Students appear to consider food as anything useful taken into an organism's body, including water, minerals and , in the case of plants, carbon dioxide or even sunlight. After learning science ideas, pupils appear to revert to their naive concepts. Driver's book has an extensive section on the misconceptions regarding plant nutrition and gas exchange on pages 30-34 and on reproduction on pages 48-53.

This learning result needs to be broken down into many parts in order to be assessed. It hits pieces of many important ideas that are complex and interrelated.

Some of the mechanisms that underlie these processes depend on concepts that students will not be exposed to until they enter high school.

The idea of global systems hinges on these ideas and is a critical one and should be assessed.

Examples

Back to Big Ideas Grid B Back to Standard B Back to Index

Curriculum Organizing Questions	Where does the water in our drinking fountain come from? What would the earth be like without decomposers? How does the statement "you are what you eat" relate to ecosystems? Where do the parts that made this organism come from? How are coal and oil formed?
Elaboration	This standard encompasses the water cycle, rock cycle, and carbon cycles and the idea of global food webs. The water cycle should be simplified and students should not be expected to understand how clouds form or the details of precipitation. Knowledge of the rock cycle in its entirety is not necessary to meet this standard, but students need to understand that rock (e.g., limestone, coal) and oil are important carbon sinks. Students should also understand the importance of photosynthesis and respiration as material cycling processes. An understanding of nitrogen fixation is not necessary at this point, but a clear understanding of the role of decay is.
Specific Ideas	Water evaporates from the surface of the earth, rises and cools, condenses into rain or snow, and falls again to the surface.Benchmarks 4B7 The water falling on land collects in rivers and lakes, soil and porous layers of rock, and much of it flows back into the ocean.Benchmarks 4B7 Plants alter the earth's atmosphere by removing carbon dioxide from it, using the carbon to make sugars, and releasing oxygen. This process is responsible for the oxygen content of the air.SFAA p. 46 All organisms are part of and depend on two main interconnected global food webs. One includes microscopic ocean plants, the animals that feed on them, and finally the animals that feed on those animals. The other web includes land plants, the animals that feed on them, and so forth. The cycles continue indefinitely because organisms decompose after death to return food material to the environment. Benchmarks 5A5 Over a long time, matter is transferred from one organism to another repeatedly, and between organisms and their physical environment. As in all material systems, the total amount of matter remains constant, even though its form and location change.Benchmarks 5E2 Food provides molecules that serve as fuel and building material for all organisms.Benchmarks 5E1 Plants use the energy in light to make sugars out of carbon dioxide and water.Benchmarks 5E1 Organisms that eat plants break down the plant structures to produce the materials and energy they need to survive. Then they are consumed by other organisms.Benchmarks 5E1
Developmental & Instructional Implications	Some middle school students think dead organisms rot away. They do not realize that the matter from the dead organism is converted into other materials in the environment. Some students think that environmental processes involve destruction and creation of matter, rather than the transformation of one substance to another. Other students may recognize one form of recycling through soil materials but fail to incorporate water, oxygen, and carbon dioxide into matter cycles. Even after specially designed instruction students cling to their misinterpretations. Instruction that traces matter through the ecosystem as a basic pattern of thinking may help correct these difficulties.Benchmarks p.343 The school science definition of food, as organic compounds which organisms can use as a source of energy for metabolic processes, is not consistently used even by science educators. Moreover, the word "food" , when used in science lessons, is used in a variety of ways both by teachers and in textbooks. Students appear to consider food as anything useful taken into an organism's body, including water, minerals and , in the case of plants, carbon dioxide or even sunlight. After learning science ideas, pupils appear to revert to their naive concepts. Driver's book has an extensive section on the misconceptions regarding plant nutrition and gas exchange on pages 30-34 and on reproduction on pages 48-53. This learning result needs to be broken down into many parts in order to be assessed. It hits pieces of many important ideas that are complex and interrelated. Some of the mechanisms that underlie these processes depend on concepts that students will not be exposed to until they enter high school. The idea of global systems hinges on these ideas and is a critical one and should be assessed.
Examples