GENERAL HISTOLOGY

Detailed explanation-1: -This is by far the largest group in the animal kingdom: 97 percent of all animals are invertebrates. So far, 1.25 million species have been described, most of which are insects, and there are millions more to be discovered.

Detailed explanation-2: -The vast majority of animal species (95 percent) are invertebrates. Among all animal species, one particular group easily claims the highest number of species: the insects.

Detailed explanation-3: -Invertebrate or Vertebrate? Approximately 97% of animals on our planet are invertebrates, or animals with no backbone.

Detailed explanation-4: -More than 90 percent of all living animal species are invertebrates. Worldwide in distribution, they include animals as diverse as sea stars, sea urchins, earthworms, sponges, jellyfish, lobsters, crabs, insects, spiders, snails, clams, and squid.

Detailed explanation-5: -Kingdom Animalia is divided into two distinct groups: vertebrates and invertebrates. Invertebrates are organisms that do not possess a vertebral column, or backbone. Invertebrate phyla include Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Arthropoda, Mollusca, and Echinodermata.