A Level Biology Practice Exam

What is an organ in biological terms?

1. A structure made of cells with no specific function

2. A collection of tissues working together to perform a function

3. A group of organs that form an organ system

4. A tissue type that has a specific role

The correct answer is: A collection of tissues working together to perform a function

In biological terms, an organ is defined as a collection of tissues that work together to perform a specific function within an organism. This organization allows for more complex processes than what individual tissues could achieve alone. For example, the heart is an organ made up of muscle tissue, connective tissue, and epithelial tissue, all working together to pump blood throughout the body. The correct choice highlights the importance of the collaboration of different tissue types in forming an organ, illustrating the hierarchical structure of biological organization: from cells to tissues to organs and finally to organ systems. This structure is essential for maintaining the overall function and health of an organism.