Ontario Grade 9 Destreamed Science (SNC1W1) 2026 Practice Exam

The primary function of the digestive system is to break down food and absorb nutrients. This process involves several organs, including the mouth, stomach, and intestines, where food is mechanically and chemically processed to extract essential nutrients such as carbohydrates, proteins, fats, vitamins, and minerals. These nutrients are vital for energy, growth, and overall health. After food is consumed, it undergoes various stages of digestion. In the mouth, it is chewed and mixed with saliva, which begins the breakdown of carbohydrates. Once it reaches the stomach, acid and enzymes further digest the food into a semi-liquid form. Finally, in the small intestine, nutrients are absorbed into the bloodstream through tiny structures called villi, allowing them to be delivered to cells throughout the body for use. While other systems perform important functions, such as delivering oxygen or eliminating waste, these activities are not the primary role of the digestive system. Thus, the main focus of the digestive system is indeed to break down food and absorb nutrients essential for maintaining bodily functions.