The animal world is diverse and amazing.They differ from each other in many biological characteristics. I would like to dwell on the relation of animals to the ambient temperature and find out: what are cold-blooded animals?
In biology, there are concepts of cold-blooded(poikilothermic) and warm-blooded (homoiothermal) organisms. It is believed that cold-blooded animals are those whose body temperature is not constant and depends on the environment. Warm-blooded animals do not have this dependence and are distinguished by the constancy of body temperature. So what animals are called cold-blooded?
In zoology, cold-blooded animals are examples.low-organized classes of the animal world. These include all invertebrates and part of the vertebrates: fish, amphibians, reptiles. The exception is crocodiles, which are also reptiles. At present, another type of mammal is also referred to this type - a naked excavator. Studying evolution, many scientists until recently attributed to cold-blooded and dinosaurs. However, at the present moment there is an opinion that they nevertheless were warm-blooded in inertial type of thermoregulation. This means that the ancient giants had the ability to accumulate and retain solar heat due to the enormous mass, which allowed them to maintain a constant temperature.
Cold-blooded animals are those thatpoorly developed nervous systems have an imperfect system of regulation of the main vital processes in the body. Consequently, the metabolism in cold-blooded animals also has a low level. Indeed, it proceeds much slower than that of warm-blooded animals (20–30 times). In this case, the body temperature is higher by 1-2 degrees of ambient temperature or equal to it. This dependence is limited in time and is associated with the ability to accumulate heat from objects and the sun, or to be warmed as a result of muscular work if approximately constant parameters are maintained outside. In the same case, when the external temperature falls below the optimum, all metabolic processes in cold-blooded ones slow down. Reactions of animals become inhibited, remember sleepy flies, butterflies and bees in the fall. When there is a decrease in temperature regime by two or more degrees in nature, these organisms fall into a stupor (anabiosis), experience stress, and sometimes die.
In the inanimate nature there is the concept of changetime of year. These phenomena are especially pronounced in the northern and temperate latitudes. Absolutely all organisms respond to these changes. Cold-blooded animals are examples of adaptations of living organisms to temperature changes in the environment.
Peak activity of cold-blooded and majorlife processes (mating, reproduction, breeding of offspring) occur in the warm period - spring and summer. At this time, we everywhere can see a lot of insects and observe their life cycles. In the near-water and water areas one can find a mass of amphibians (frogs) and fish at different stages of development.
In forests and meadows, reptiles (lizards, snakes, snakes) of different generations are quite common.
With the arrival of autumn or late summer animalsbegin to intensively prepare for the wintering, which most of them spend in suspended animation. In order not to die during the cold season, the preparatory processes for the supply of nutrients in their bodies occur in advance, throughout the summer. At this time, the cellular composition changes, it becomes less water and more dissolved components that will ensure the process of nutrition throughout the winter period. With a decrease in temperature, the level of metabolism also slows down, energy consumption decreases, which allows cold-blooded people to spend the whole winter in hibernation, not caring for food. Also an important stage of preparation for adverse temperature conditions is the construction of enclosed "rooms" for wintering (pits, burrows, houses, etc.). All these life phenomena are cyclical in nature and are repeated from year to year.
These processes are also unconditional.(congenital) reflexes inherited from generation to generation. Animals that undergo certain mutations in the genes responsible for the transmission of this information die during the first year of life, and their offspring may also inherit these disorders and be unhealthy.
The impetus for waking up from anabiosis is an increase in air temperature to the required level, which is characteristic of each class and sometimes of a species.
According to evolutionary theory, cold-blooded animals are inferior creatures, in which, due to the weak development of the nervous system, the mechanisms of thermoregulation are also not perfect.
