Which of the following is NOT an example of a biological system?
a) A human eating a cheeseburger.
b) A coral reef where energy and mass both enter and exit.
c) The digestive system of an organism absorbing food energy and discarding food waste.
d) The universe where the amount of energy and mass is constant.

• A. A human eating a cheeseburger.
• B. A coral reef where energy and mass both enter and exit.
• C. The digestive system of an organism absorbing food energy and discarding food waste.
• D. The universe where the amount of energy and mass is constant.

Answer: (D)

Verified step by step guidance

1. Understand the concept of a biological system: A biological system is a complex network of biologically relevant entities. It typically involves the exchange of energy and matter with its surroundings.
2. Analyze option a: A human eating a cheeseburger involves the intake of energy and nutrients, which is a characteristic of a biological system.
3. Analyze option b: A coral reef is an ecosystem where energy and mass are exchanged with the environment, fitting the definition of a biological system.
4. Analyze option c: The digestive system processes food, absorbing energy and nutrients while discarding waste, which is a typical biological system function.
5. Analyze option d: The universe, where energy and mass are constant, does not exchange energy or matter with its surroundings, thus not fitting the definition of a biological system.