How many parts of the body do insects have? It consists of clearly delineated segments, which include the abdomen, head and chest. These parts include numerous appendages. Let’s take a closer look at how many departments the body of insects consists of. What specific organs and elements are part of individual segments?
External skeleton
Insects are classified as invertebrate creatures. Based on this, their skeleton is fundamentally different from the skeleton of mammals. The integrity of the animal body is maintained by the bone apparatus. The base of the latter is the spine, from which the ribs, bones of the limbs, pelvis and neck depart. The movement is facilitated by the presence of muscles. The situation is different with insects.
Invertebrates possess not an internal but an external skeleton. Primitive muscle joints provide its mobility from the inside. The body of insects is formed by the so-called cuticle - a dense chitinous membrane. The joints are connected by numerous lamellar segments. Despite its light weight, the skeleton of insects is strong enough. It is impervious to moisture and air. A specific feature of such a shell is that it does not grow together with soft tissues. It is for this reason that insects are forced to periodically drop protective shells and form new shells.
How many parts of the body are insects that have not yet reached maturity? Usually, larvae differ in structure from adult individuals. They have no external skeleton. The cuticle during ripening is particularly flexible. This is due to the fact that during development, the body of the larva extremely rapidly increases in volume. Therefore, he needs free space for stretching. Some caterpillars, before reaching maturity, drop the outer cover several tens of times. Over time, a constant, dense shell forms.
Head
How many departments does the body of insects have? As we found out, among the main parts there are three segments. The front section is the head. In most species, it is presented in the form of a capsule. On the surface of the cuticle that covers the head, there are so-called sclerites. They are separate particles of a dense shell, interconnected by seams.
A typical insect head is represented by the facial, ventral, lateral and dorsal segments. In this part of the body, the parietal and frontal zone, cheeks, clypeus, upper lip are distinguished. Here there are simple or complex faceted eyes, as well as adnexa in the form of antennae and oral apparatus.
Chest
Answering the question of how many parts of the body are in insects, let's talk about the thoracic segment. It is located between the head and the abdomen. In most cases, the department has a shape similar to a cylindrical one. Appendages adjoining to a breast in the form of paired paws and wings. Their number in individual insects can vary.
The chest is divided into several segments: mesothorax, prothorax and posterior chest. These segments are formed by half rings. The latter are interconnected by membrane structures. Such elements of the breast are not evenly developed in individual insects. It all depends on the method of movement and lifestyle.
Abdomen
Considering the external structure of the body in insects, how many departments they have, it is necessary to talk about the abdominal segment. This part contains internal organs. Like the chest, the abdomen of various insects may differ according to the specific structure. On the outer surface there is a significant number of appendages. In particular, there are so-called spiracles. These appendages act as trachea inlets through which the insect absorbs oxygen from the environment. In the posterior segments of the abdomen are the reproductive organs and the anus.
So we found out how many parts of the body have insects. Photos of these segments can be seen in our article. Next, I would like to talk about the main appendages that are adjacent to these departments.
Eyes
Considering what structure and how many parts of the body of insects, it is necessary to say a few words about the organs of vision of such creatures. Some representatives of such invertebrate eyes may consist of tens of thousands of special cells, each of which is responsible for the perception of a narrow beam of light rays. This vision is called facet. In other words, the image is formed into a single picture from a whole mass of individual points. Despite the fact that the insect perceives objects rather vaguely, the eye gets the opportunity to capture the surrounding space in a wide field of view. Such a feature of the receptor helps to capture any movement both from the side of the enemies and potential prey.
In fact, not all insects have facet eyes. Some members of the class of such invertebrates have simple eyes. The latter are formed from a layer of receptor cells, a photosensitive lens and pigment.
Oral apparatus
The appendage of the head of the insect is the oral apparatus. Based on the preferred food, the segment may have its own unique structure. Nevertheless, it distinguishes structural elements common to all insects. The oral apparatus includes several pairs of maxillas or mandibles, the function of which is the capture of food. It also contains the so-called sub-pharynx, which allows the insect to push particles of prey into the oral cavity.
Antennae
Having found out how many departments the body of insects has, it’s worth talking about such an important external organ of these creatures as antennae or antennae. They are presented as a series of segments of a separate shape and size. The antennae are responsible for the smell of the insect, allow individual species to determine the temperature of the surrounding space, the level of humidity, perceive ultrasonic waves.
Legs
The legs act as an appendage of the thoracic region of the body. How many insects have limbs? Of these, most representatives of creatures of this class have three pairs. A standard insect leg consists of the following parts:
- Basin.
- Hips.
- Lower legs.
- Swivel.
In most cases, the legs contain suction cups or claws to grip surfaces. Some insects have legs with all kinds of combs, hairs, spikes, and ribs. The limbs are able to slightly change depending on the habitat of the invertebrate, the method of movement, lifestyle. Individual legs are responsible for capturing prey, moving, etc.
In larvae, the legs do not differ in different specializations. The structure of the legs in immature individuals is homogeneous and simplified. They can be located along the entire body both in the region of the thoracic and abdominal segment.
Wings
The wings of insects act as appendages of the thoracic region. Invertebrates, as a rule, have several pairs. These appendages can have a very different form, structure, shade and structure. Be that as it may, the wings necessarily include the basal part, which connects to the skeleton and is responsible for mobility, as well as the membranous apical segment.
