Information about animal manuscripts, the contents of animal manuscripts.

1. Animals are a large group of multicellular eukaryotes, but they are different from microorganisms.

Animals can't synthesize inorganic matter into organic matter. They can only take organic matter as food, which they can eat and rely on. They are made up of cells, with nuclei, no cell walls, no movement and no substrate.

3. Therefore, animals have different morphological structures and physiological functions from plants from feeding, digestion, absorption, breathing, circulation, excretion, feeling, exercise to reproductive life activities.

4. Zoology classifies animals with the same or similar characteristics into the same category according to their morphology, internal structure, embryonic development characteristics, physiological habits and geographical environment.

5. They are mainly divided into two categories: chordates and animals without chordates; According to aquatic or terrestrial animals, it can be divided into aquatic animals and terrestrial animals; According to whether there are feathers, it can be divided into feathered animals and featherless animals; According to whether there is a spine in the body, we can divide all animals into vertebrates and invertebrates.

6. After the appearance of primitive life, with the change of living environment, millions of species have appeared and become extinct, and only those species that can adapt to environmental changes have survived and multiplied to this day. The process of continuous evolution of this species is biologically called evolution.

7. Animals are a big category of living things, called the animal kingdom.