Final answer:
Figures with radial symmetry like echinoderms, jellyfish, and sea anemones have point symmetry, allowing them to maintain their appearance when rotated around a central point, unlike bilaterally symmetrical figures such as humans and butterflies.
Step-by-step explanation:
Understanding Point Symmetry in Biological Figures
Point symmetry, also known as rotational symmetry, occurs when every part of a figure or organism is arranged around a central point so that the structure can be rotated at some angle and still appear the same as it did before the rotation. In the context of biology, radial symmetry is a type of point symmetry that we can see in certain organisms. For instance, the echinoderms which exhibit a five-part radial symmetry showing point symmetry, can rotate around the central axis and still maintain the same appearance from multiple angles. Similarly, organisms such as jellyfish or sea anemones also have radial symmetry, allowing rotation around their central axis without changing their appearance.
On the other hand, the human body and a butterfly exhibit bilateral symmetry, which is different from point symmetry as they can only be divided into two equal halves by a single plane. Animals that have asymmetry, such as sponges, do not have any kind of symmetry, point included. When considering animals that have point symmetry, the jellyfish, anemones, and certain echinoderms would be included, whereas humans, butterflies, and sponges would not. In summary, figures with radial symmetry, such as those of some echinoderms, jellyfish, and anemones, have point symmetry while those with bilateral symmetry, like humans and butterflies, do not.