Sophie tackles the question of why there are so many different breeds of dogs. She briefly discusses the history of dogs and discusses how genetics makes dogs different and why some breeds are better suited for certain functions.
Sophie illustrates the six basic simple machines that exist and explains how they are useful in our everyday lives. She defines force and work and mentions that simple machines reduce the amount of work required for a task.
Sophie explains why we eat food: to ingest chemicals such as nutrients. She dissects a salad to illustrate the different types of nutrients our body needs: carbohydrates, proteins, and fats. She provides an example of each type of nutrient.