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Animals | Activity 5.3

Activity 5.3: Explaining How Cows Grow: Digestion and Biosynthesis (40 min)

Students use the Explanations Tools to explain cow digestion and biosynthesis.

Note: This lesson should be taught, regardless of it you taught only Activity 5.1 or both Activity 5.1 and 5.2. However, the language you use and the responses you should expect from your students will be different. Students who did 5.2, molecular modeling, should use the terms “polymers” and “monomers” in their explanations of digestion and biosynthesis, including the names of specific polymers (e.g., proteins, fats and carbohydrates) and monomers (e.g., amino acids, fatty acids, glycerol). Students only did 5.1 should use the terms "large organic molecules" and "small organic molecules" rather than polymers and monomers and use the names of specific large organic molecules (e.g., proteins, fats and carbohydrates) only. Throughout the PPT, you will find both sets of vocabulary.

Resources Provided


Print one copy of the 5.3 Explanations Tool for Cow Digestion and 5.3 Explanations Tool for Cow Biosynthesis for each student. Prepare a computer and a projector to display the PPT. Print and hang the Digestion and Biosynthesis 11 x 17 Posters.


1. Use the instructional model to show students where they are in the course of the unit.


Use 5.3 Grading the Explanations Tools for Cow Digestion and 5.3 Grading the Explanations Tools for Cow Biosynthesis to grade student responses. This worksheet has “grading” in the title (instead of “assessing”) because at this point, students can be held accountable for correct answers. If students are still struggling with these concepts, you may want to revisit parts of the activity they are finding difficult.