Timss 2011 Science Framework Chapter 2

 
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Biology: Ecosystems
1.
Describe the flow of energy in an ecosystem; identify 
different organisms as producers, consumers, and 
decomposers; draw or interpret food pyramids or food web 
diagrams.
2.
Describe the role of living things in the cycling of elements 
and compounds (e.g., oxygen, carbon, water) through 
Earth’s surface and the environment.
3.
Explain the interdependence of populations of organisms 
in an ecosystem in terms of the effects of competition and 
predation. 
4.
Identify factors that can limit population size (e.g., disease, 
predators, food resources, drought); predict effects of 
changes in an ecosystem (e.g., climate, water supply, 
population changes, migration) on the available resources 
and the balance among populations. 
5.
Recognize that the world’s human population is growing 
and identify reasons why (e.g., advances in medicine, 
sanitation); discuss the effects of population growth on the 
environment.
Biology: Human Health
1.
Describe causes of common diseases (e.g., influenza, 
measles, strep throat, malaria, HIV), methods of infection
or transmission, prevention, and the importance of the 
body’s resistance (immunity) and healing capabilities.
2.
Explain the importance of diet, exercise, and lifestyle 
in maintaining health and preventing illness (e.g., heart 
disease, high blood pressure, diabetes, skin cancer, 
lung cancer); identify the dietary sources and role of 
nutrients in a healthy diet (vitamins, minerals, proteins, 
carbohydrates, fats).

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TIMSS 2011 SCIenCe FraMework 
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Chemistry
In the area of chemistry, students will be assessed on their 
understanding of concepts related to the following topic areas:
• Classification and composition of matter
• Properties of matter
• Chemical change
At the eighth grade, students should be able to classify substances 
on the basis of characteristic physical properties and recognize 
that substances can be grouped according to similar chemical and 
physical properties. They are expected to differentiate between 
elements, compounds, and mixtures in terms of their composition. 
They also are expected to have a beginning understanding of the