Have you ever wondered what an insect looks like inside? Or whether an insect has a heart or a brain?
The insect body is a lesson in simplicity. A three-part gut breaks down food and absorbs all the nutrients the insect needs. A single vessel pumps and directs the flow of blood. Nerves join together in various ganglia to control movement, vision, eating, and organ function.
This diagram represents a generic insect, and shows the essential internal organs and structures that allow an insect to live and adapt to its environment. Like all insects, this pseudo bug has three distinct body regions, the head, thorax, and abdomen, marked by the letters A, B, and C respectively.
In this article, you'll learn about each of the insect's body systems: nervous, digestive, circulatory, respiratory, reproductive, and excretory. As you read about each system, use the diagram to identify the organs and structures discussed.
This original diagram of the internal anatomy of an insect was created by Piotr Jaworski, and licensed through Creative Commons. You can see more of his excellent graphics work on his Wikimedia Commons user page. On the following pages, I have modified his diagram to highlight only the organs and structures of the body system discussed on that page.