DENDROLOGY

Detailed explanation-1: -Fish are aquatic vertebrate animals that have gills but lack limbs with digits, like fingers or toes. Recall that vertebrates are animals with internal backbones. Most fish are streamlined in their general body form. The word fish is the same whether it is singular or plural-you can talk about one fish or ten fish.

Detailed explanation-2: -The phylum chordata (animals with backbones) is divided into five common classes: fish, amphibians, reptiles, mammals and birds.

Detailed explanation-3: -“Vertebrate” means that a fish has a skeleton with a spine. Most fish have a skeleton made from bone, just like amphibians, reptiles, birds, and mammals.

Detailed explanation-4: -A fish is any of approximately 34, 000 species of vertebrate animals. The term fish is applied to a variety of vertebrates of several evolutionary lines.