Michigan Test for Teacher Certification (MTTC) Secondary Integrated Science Practice test

Which of the following is NOT a characteristic of living things?

1. Made of cells

2. Capable of reproduction

3. Inability to respond to stimuli

4. Carry on metabolic processes

The correct answer is: Inability to respond to stimuli

The correct answer highlights a fundamental concept in biology: living things possess the ability to respond to stimuli, which is essential for their survival and adaptation. This characteristic allows organisms to interact with their environment, ensuring they can detect changes and react accordingly. Whether it's plants bending toward sunlight or animals fleeing from predators, responsiveness to environmental cues is a hallmark of life. Conversely, the other characteristics listed are essential traits that define living organisms. All living beings are made up of cells, which are the basic units of life. They also have the capability of reproduction, whether through sexual or asexual methods, allowing for the continuation of their species. Additionally, all living organisms carry on metabolic processes, which include the biochemical reactions necessary for maintaining life, such as energy production and waste elimination. Therefore, the inability to respond to stimuli is not a characteristic of living things, making it the accurate answer in this context.