Why Do Skates and Rays Have Flattened Bodies, While Sharks

question 22

Multiple Choice

Why do skates and rays have flattened bodies, while sharks are torpedo shaped?

• A) Sharks are more closely related to the tube-like lampreys than are skates and rays.
• B) Skates and rays need enlarged pectoral fins to help them stay level in turbulent water, while sharks do not.
• C) Skates and rays exchange gases across their skin and thus require a high surface-area-to-volume ratio, while sharks use gills to respire.
• D) Sharks are streamlined for active swimming at mid-depths, while skates move about mostly on the ocean bed.