What are the characteristics of insects?

There are not only many species of insects, but also an astonishing number of individuals of the same species. The distribution of insects is so wide that there is no other class of animals that can be compared with it. There are almost all over the world and there are different species. Do you know the characteristics of them? Now let's take a look at the characteristics of insects.

The characteristics of insects

1. There is a shell-like structure outside the body, so it is usually hard.

2. Section by section can be identified clearly in appearance.

3. It can be divided into three parts: head, chest and abdomen.

4. The head usually has a pair of antennae, a pair of eyes (compound eyes) and a mouthpiece.

5. There are usually two pairs of wings above the chest and three pairs of feet (feet) below.

If all the conditions meet the above characteristics, we can say: it is an insect! However, this does not mean that all insects have these characteristics, and there are still many insects without some of these characteristics, for example, some insects have only one pair of wings or even no wings at all, some insects have no eyes, some insects have missing a pair of feet or no feet at all, some insects have soft bodies, and so on.

Structure of insects

The bodies of insects seem to be connected one by one, which is why they are called arthropods. Now let's take a closer look at the structure of insects. First of all, their bodies can be divided into three main parts: head, chest and abdomen.

1. Head

① antennae: a pair of antennae grow at the front and top of the head, and the shape varies greatly from insect to insect. Tentacles are like human noses, mainly for smelling; in addition, the antennae of some insects have the function of feeling air vibration.

② compound eyes: a pair of compound eyes grow on both sides of the head. It is made up of many small eyes. The function of the compound eye is the same as our eyes, used to see things. Its structure often varies with different insect species.

③ monocular: the monocular is a very obscure structure located between the two compound eyes. Although it is a kind of eye, insects do not use it to see things, but use it to help compound eyes distinguish between light and dark. In some insects, it even degenerated and disappeared.

④ mouthparts: mouthparts are the mouths of insects and are used to eat. There are two most common mouthparts, one is locust-like mouthparts, which have two large jaws for chopping food, and the other is needle-like mouthparts that can pierce the skin and suck blood. In addition, mouthparts may vary with different insect species.

2. Chest

The chest is the location of the main motor organs of insects. From the foreign officials, it can be divided into three sections, namely, the front chest, the middle chest and the back chest. There is a pair of feet on both sides below each sternal segment, so there are three pairs (six) feet in the three sternal nodes. In addition, the upper part of the middle chest and the back chest usually have a pair of wings, so insects usually have two pairs (four) of wings.

① wings: wings are the structures used by insects to fly; however, like other structures, wings vary significantly from insect species to insect species.

② feet: feet are used by insects to crawl; however, some insect feet have different functions, such as digging, grasping or catching.

3. Abdomen

Compared with the first two parts, the structure of the insect abdomen is relatively simple, there are not too many accessory structures, the more obvious structure should be the genitals at the end, the male's copulation or the female's oviposition.

Until the beginning of the 21st century, there are about 1 million species of insects known to mankind, but there are still many species to be discovered.