Georgia Pest Control Practice Test

Which of the following is not a shared feature of humans, insects, and arthropods?

1. Central nervous system

2. Closed circulatory system

3. Striated muscles

4. Bilateral symmetry

The correct answer is: Closed circulatory system

The closed circulatory system is not a shared feature among humans, insects, and arthropods. Humans possess a closed circulatory system where blood circulates within vessels, allowing for efficient transport of nutrients and oxygen. In contrast, insects and many arthropods have an open circulatory system, meaning that blood, or hemolymph, freely flows through cavities and is not always contained within vessels. In addition to this, the other features mentioned are prevalent across the groups. Both humans and arthropods (including insects) exhibit bilateral symmetry, which is a characteristic body plan where the left and right sides are mirror images. Central nervous systems vary in complexity between these organisms, but they all have some form of a centralized nervous system that processes information and coordinates responses. Striated muscles are present in humans (for voluntary movement) and also can be found in some types of arthropods, contributing to their movement and functionality. Thus, the distinguishing factor here is the type of circulatory system, which is fundamentally different between these groups.