How does a spider differ from insects: structural features
Nature is full of all sorts of amazing representatives. The Arthropod type boasts the largest number, the two most prominent representatives are insects and arachnids. They are very similar, but also very different.
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Arthropods: who are they
Arthropods.
The name speaks for itself. Arthropods are a series of invertebrates with articulated appendages and a segmented body. The body consists of two sections and an exoskeleton.
Among them there are two types:
- arachnids, which include spiders, scorpions and ticks;
- insects, of which there are a lot - butterflies, midges, flies, bugs, ants, etc.
Who are insects
representatives of insects.
Insects are small invertebrates, often with wings. Sizes vary, from a few mm to 7 inches. The exoskeleton is made of chitin, and the body consists of a head, chest and abdomen.
Some individuals have wings, an antenna, and complex organs of vision. The life cycle of insects is a complete transformation, from eggs to adults.
Arachnids
Representatives of arachnids do not have wings, and the body is divided into two parts - the belly and cephalothorax. The eyes are simple and the life cycle begins with an egg, but no metamorphosis occurs.
Similarities and differences between insects and arachnids
These two families have a number of similarities. Both families:
- arthropods;
- invertebrates;
- segmented body;
- most are terrestrial;
- articular legs;
- there are eyes and antennae;
- open circulatory system;
- digestive system;
- cold-blooded;
- dioecious.
Differences between insects and arachnids
| Definition | Insects | Arachnids |
| Appendages | Three couples | Four pairs |
| Wings | Most | No |
| Mouth | Jaws | chelicerae |
| Body | Head, chest and belly | Head, abdomen |
| Antennas | A pair | No |
| Eyes | Complex | Plain, 2-8 pieces |
| Breath | Trachea | Trachea and lungs |
| Blood | Colorless | Blue |
The role of animals
Both those and those representatives of the animal world have a certain role in nature. They take their place in the food chain and are directly related to people.
Yes, a row insects are domesticated by man and his assistants.
Arachnids are ubiquitous and each has its own role. They can be helpful to people or cause a lot of damage.
Conclusion
Often spiders are called insects and these representatives of the animal world are confused. However, in addition to the general type, Arthropods, they have more differences in internal and external structure.
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