Instead of nostrils near the nooe,what do cetaceans have through which to breathe air? a nose a blow hole gills

## Step 1<br />The question is asking about the respiratory system of cetaceans, which include species such as dolphins, whales, and porpoises. These marine mammals have a unique adaptation that allows them to breathe air while underwater.<br />## Step 2<br />Cetaceans do not have nostrils near their nose, as in humans. Instead, they have a blowhole, which is a specialized opening on the top of their head.<br />## Step 3<br />The blowhole is used for breathing. When a cetacean needs to breathe, it surfaces and opens its blowhole to take in air. The air then travels down the respiratory tract and into the lungs.<br />## Step 4<br />The blowhole is not used for smelling or other sensory functions. It is solely for breathing.<br />## Step 5<br />The options "a nose" and "gills" are incorrect. Cetaceans do not have nostrils near their nose, and they are not fish, so they do not have gills.