How Your Body Rebuilds Food
Aligned to MS-LS1-7 — Next Generation Science Standards.
What this lesson teaches
When an organism eats, chemical reactions break food molecules apart and rearrange the atoms into new molecules. Some of these new molecules build and repair the body, while others are broken down further to release stored energy.
Worked example
The starch in a slice of bread is broken into sugar during digestion; inside your cells, that sugar reacts with oxygen and its atoms are rearranged, releasing energy to move your muscles and giving off carbon dioxide you breathe out.
Practice questions
- Chew a plain cracker slowly and notice how it starts to taste sweet as starch breaks into sugar.
- Draw a model showing how atoms from food are rearranged into new molecules for building the body and releasing energy.
- Explain, using the idea of rearranged atoms, why you breathe out carbon dioxide after using energy from food.
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
Cómo tu cuerpo reconstruye el alimento
Cuando un organismo come, las reacciones químicas separan las moléculas del alimento y reorganizan los átomos en nuevas moléculas. Algunas de estas nuevas moléculas construyen y reparan el cuerpo, mientras que otras se descomponen aún más para liberar energía almacenada.
Ejemplo: El almidón de una rebanada de pan se descompone en azúcar durante la digestión; dentro de tus células, ese azúcar reacciona con el oxígeno y sus átomos se reorganizan, liberando energía para mover tus músculos y desprendiendo dióxido de carbono que exhalas.
More From Molecules to Organisms: Structures & Processes lessons
Teach this lesson today
An AI tutor that guides with questions instead of just giving answers — all K–12 core subjects, every child in the family.
Start free — no card required