Final answer:
Seeds dispersed by animals have specific adaptations like hooks or fleshy fruits, while wind and water dispersed seeds are lightweight and have structures like wing-like appendages.
Step-by-step explanation:
Comparison of Seed Structures
Seeds dispersed by animals and those dispersed by wind and water have different structures.
Seeds dispersed by animals:
1. These seeds often have a hard outer covering that protects them during animal digestion.
2. Some seeds have hooks, spines, or barbs that attach to an animal's fur, feathers, or skin, allowing them to be transported.
3. Others have fleshy or tasty fruits that animals eat, and the seeds are later dispersed through animal droppings.
Seeds dispersed by wind and water:
1. These seeds are lightweight, with structures that aid in dispersal.
2. Some seeds have wing-like appendages that allow them to be carried by the wind, like dandelion seeds.
3. Other seeds have structures that keep them afloat in water, like coconut seeds.
Example:
An acorn is an example of a seed dispersed by animals. It has a hard outer covering and is commonly cached and forgotten by animals like squirrels, allowing it to sprout in a new location. On the other hand, a dandelion seed is an example of a seed dispersed by wind. It has a lightweight structure with feather-like appendages that help it travel long distances in the wind.