A model shows a fish repairing a torn fin. In the before panel, small molecules are shown inside the fish near the tear. Arrows show them being assembled into larger structures that fill the torn area. In the after panel, the fin is whole again. The model states: "Rearranged molecules support growth and repair."
Which claim about the model is incorrect?
- Repair happens when small molecules are rearranged and built into larger structures that become fin tissue.
- The arrows suggest that molecules are connected into larger structures during repair.
- The fin repairs because the fish creates brand-new matter, so the small molecules do not need to come from anywhere. (correct answer)
- The before-and-after panels show a change in the fin that can be explained by building new tissue from molecules already in the body.
Explanation: The core concept in middle school life science is that molecules support the growth and repair of living organisms by providing the building blocks for new tissues. Small molecules, such as those from food, are rearranged inside the body to form the complex structures needed for healing processes like repairing a torn fin in a fish. Models demonstrate this by using arrows to illustrate how small molecule pieces are connected into longer chains and stacked layers that fill in damaged areas and create new tissue. To check your understanding, count the small molecules in the before panel and ensure they match the components in the larger structures of the after panel, confirming no matter is created or destroyed. A common misconception is that repair involves creating brand-new matter, but in reality, all new tissue comes from rearranging existing molecules. Conserved matter ensures that organisms can repair themselves efficiently without needing to produce matter anew. This principle of matter conservation supports both growth and repair across all living things, allowing for sustainable development and recovery.