Your Body as Teamwork of Systems
Aligned to MS-LS1-3 — Next Generation Science Standards.
What this lesson teaches
Your body is made of subsystems that interact so you can survive. Groups of similar cells form tissues, tissues form organs, and organs work together as systems that depend on each other — the digestive system releases nutrients, the circulatory system delivers them, and the respiratory system supplies oxygen the cells need.
Worked examples
Example 1
When you run, your respiratory system takes in more oxygen, your circulatory system pumps blood faster to carry it, and your muscular system uses it to move — evidence that the systems are not separate but constantly signaling and supporting one another.
Example 2
Your digestive system breaks food into molecules small enough for the circulatory system to carry — neither one works without the other.
Example 3
A single system failing takes others with it. Kidney failure changes blood chemistry, which affects the heart and the nervous system.
Practice questions
- Feel your pulse before and right after 20 jumping jacks and record what changed.
- Draw arrows on a body outline showing how the digestive, circulatory, and respiratory systems pass materials to each other.
- Argue with evidence why a problem in one body system, like blocked lungs, quickly affects the others.
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Tu cuerpo como trabajo en equipo de sistemas
Tu cuerpo está formado por subsistemas que interactúan para que puedas sobrevivir. Los grupos de células parecidas forman tejidos, los tejidos forman órganos, y los órganos trabajan juntos como sistemas que dependen unos de otros — el sistema digestivo libera nutrientes, el sistema circulatorio los reparte, y el sistema respiratorio suministra el oxígeno que las células necesitan.
Ejemplo 1: Cuando corres, tu sistema respiratorio toma más oxígeno, tu sistema circulatorio bombea la sangre más rápido para transportarlo, y tu sistema muscular lo usa para moverse — evidencia de que los sistemas no están separados, sino que se comunican y se apoyan constantemente.
Ejemplo 2: Tu sistema digestivo descompone la comida en moléculas lo bastante pequeñas para que el circulatorio las transporte — ninguno funciona sin el otro.
Ejemplo 3: Si un sistema falla, arrastra a otros. La falla renal cambia la química de la sangre, lo que afecta al corazón y al sistema nervioso.
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