Use this inviting crossword puzzle to introduce and review important vocabulary words for a unit on photosynthesis, plant respiration, and the carbon cycle. Puzzles make great no prep activities for early finishers, bell ringers, morning work, handouts, homework, lesson plan supplements, sponge activities, introductions to new topics, and sub files.The vocabulary words covered are the following: Animals, Carbon dioxide, Chlorophyll, Chloroplast, Cytoplasm, Energy, Glucose, Green, Mitochondria,