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Unit: Nervous & Endocrine

Aligned to Science TEKS with clear Learning Outcomes, this unit covers instructional content including, Levels of Organization of Nervous System, Senses, Responses to Stimuli, Levels of Organization of Endocrine System, and Maintaining Homeostasis.


  • 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
  • 11A  Describe the role of internal feedback mechanisms in the maintenance of homeostasis
  • 11B  Investigate and analyze how organisms, populations, and communities respond to external factors