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Unit: Circulatory & Respiratory

Aligned to Science TEKS with clear Learning Outcomes, this unit covers instructional content including Function of Circulatory System, Components of Blood, Types of Blood Vessels, Structure of Heart, Function of Respiratory System, Anatomy of Respiratory System, and Interactions of Circulatory and Respiratory Systems in Homeostasis.


  • 4B  Investigate and explain cellular processes, including homeostasis, energy conversions, transport of molecules, and synthesis of new molecules
  • 5B  Examine specialized cells, including roots, stems, and leaves of plants; and animal cells such as blood, muscle, and epithelium
  • 10A  Describe the interactions that occur among systems that perform the functions of regulation, nutrient absorption, reproduction, and defense from injury or illness in animals
  • 10C  Analyze the levels of organization in biological systems and relate the levels to each other and to the whole system