Animal body circulation 50, animal blood circulation

Systemic circulation. macrocirculation) and pulmonary circulation (small circulation) processes:

Systemic circulation (macrocirculation): When the ventricles contract, fresh blood containing oxygen and nutrients (arterial blood) flows from the left ventricle into the aorta.

It then branches along the arteries at all levels to the capillaries of all parts of the body. Here the blood exchanges substances with the surrounding cells and tissues, and the nutrients and oxygen in the blood are absorbed by the cells and tissues, their metabolites and carbon dioxide.

and so on into the bloodstream. The blood changes from bright red arterial blood to dark red venous blood. It then passes through all levels of veins and finally flows back to the right atrium through the superior and inferior vena cava.

The main characteristics of systemic circulation are: long distance, wide flow range, arterial blood nourishes all parts of the body, and its metabolites are transported back to the heart.

Pulmonary circulation (small circulation): Venous blood that circulates back to the heart from the body and enters the right ventricle from the right atrium. When the ventricles contract, blood ejects from the right ventricle, travels through the pulmonary arteries into the lungs, and then branches through the pulmonary arteries into the alveoli.

around the capillary network. Through the capillary wall and the very thin alveolar wall, the blood exchanges gas with the air in the alveoli, excretes carbon dioxide, inhales fresh oxygen, and turns the venous blood into oxygen-rich arterial blood, which is then discharged through the pulmonary veins and injected into the left atrium. Blood flows from the left atrium into the left ventricle.

The pulmonary circulation is characterized by a short distance, passing only through the lungs, and its main function is to convert venous blood into oxygen-rich arterial blood.

The reason why animals can promote the material cycle of the ecosystem is that animals are generally consumers, and animals are maintaining ecological balance, mainly by realizing the carbon cycle and the relationship between eating and being eaten.

The role of animals in ecological balance: Animals are important components of the food chain and food web, and play a very important role in maintaining ecological balance.

In the process of long-term survival and development, animals and plants in nature form a relationship of mutual adaptation and interdependence. Animals are able to help pollinate plants so that these plants can reproduce smoothly, such as bees collecting nectar, and the symbiosis of figs and pollinators. Animals can help plants disperse their seeds, which is conducive to expanding the distribution range of plants, such as hooked thorns hanging on the surface of the fruit of the egg.

When there are too many animals in certain rental heights, it can also cause damage to plants, such as locust plagues.

The relationship between animal disadvantages and human life.

Animals and bioreactors: The use of animals as a "production workshop" to produce certain substances needed by human beings is a bioreactor. Imitating certain structures and functions of animals to invent and create various instruments and devices is biomimicry.

For example, airplanes, submarines, Exocet missiles, fluorescent lights, and cameras are all masterpieces of bionics. Animals can also provide humans with fur and meat, and some animals can also take care of homes for humans.

Generally speaking, there is no diaphragm in the middle of the heart of animals, that is, there are only two chambers of the atrium and ventricle, and there is no distinction between the left atrium and the right atrium. The first is that the efficiency of transporting oxygen is reduced, which makes the metabolism relatively slow, which is not conducive to providing energy and maintaining body temperature. The blood circulation of ectotherms is basically in this state, so their distribution is very limited by geography.

The transport efficiency is low, which limits the range and range of movement of the animals.

The biological cycle refers to the material cycle in the ecosystem, that is, the process of the flow of substances between the biotic and non-biotic components in the ecosystem. Nutrients from the atmosphere, water and soil and other natural environment through the absorption of green plants, into the ecosystem, flow among various organisms in the ecosystem, and finally return to the environment, complete a cycle, the whole process continues, the returned substances are absorbed by plants into the ecosystem again, and the cycle continues, the repeated transmission and transformation process of this substance is called the material cycle.

At the heart of the biological cycle is photosynthesis in plants.

The circulation of matter in the ecosystem, energy is not recyclable, and energy is dependent on matter.

To take the example of the C cycle, isn't it advocating a low-C life now?

Sunlight (energy) shines on producers, who use inorganic substances and their ability to synthesize organic substances (sugars, etc.).

Organic matter is used by consumers at the first level, c is also transmitted with the consumer level, and finally, the organism dies, the decomposer decomposes the organic matter, c becomes CO2 and returns to the inorganic environment, and then is used by the producer...

1.Annelid. Annelids are lower than mollusks and appear early. Neuromorphs develop the circulatory system earlier than annelids.

However, because it is too simple, it is generally ignored and it is believed that the circulatory system originated from annelids.

2.Both open-tube and closed-tube cycles exist. Most of them are open-tube; A few are closed-tube cycles, such as cephalopod squid.

Circulatory system in animals: A general term for a set of closed tubes that transport blood and lymph to humans and animals. The circulatory organs of humans and mammals generally include the heart, arteries, capillaries, veins, and lymphatic vessels.

There are two circulatory pathways, namely systemic circulation and pulmonary circulation. The systemic circulation, also known as the "large circulation", blood pours from the left ventricle into the aorta, then through the middle and small arteries, to the capillaries of the whole body for material exchange, and finally from the small vein, large vein, superior and inferior vena cava back to the right atrium, into the pulmonary circulation. The pulmonary circulation, also known as the "small circulation", involves blood flowing from the right ventricle down the pulmonary artery, through the pulmonary capillaries, for gas exchange, and then through the pulmonary veins back to the left atrium.

The lymphatic system consists of small lymphatic vessels that merge into large lymphatic vessels, which finally merge into a thoracic duct and a right lymphatic duct, which open into a large vein at the base of the neck and inject lymph into the vein to participate in the blood circulation. This circulating phenomenon in which blood transports nutrients and oxygen repeatedly in a closed tube is also known as a closed tube circulation. The blood of mussels, insects and other animals flows from the heart through the arteries into the sinuses or blood cavities, directly infiltrates various tissues and organs, and finally returns to the ventricles through the veins or blood sinuses.

This circulating phenomenon in which blood is not completely enclosed in the blood vessels is called open-tube circulation. The circulatory system has the functions of transporting substances, regulating body temperature and internal environment, and resisting diseases.

Animals, as consumers, contribute to the material cycle of the biosphere, such as helping plants pollinate and disperse seeds; Substances such as carbon dioxide and urine are produced for use by producers; It can also control pests, etc. Why animals are a promoter, is because animals for the biosphere, dispensable, with animals make the biosphere material cycle more diverse, more rapid, play a positive role, of course, if there are no animals, the biosphere material cycle will not stop, will continue. Think of it, if there were no animals, plants would survive through photosynthesis and synthesize organic matter, and after death the body would be decomposed by the decomposer, and the organic matter would become inorganic.

Inorganic matter is used by the plant body, and the cycle continues.

Bacteria and fungi are an integral part of the biosphere's material cycle, and if there were no decomposers on the earth, how would the remains of living beings be stacked over the years? There are living things everywhere, and oxygen and so on will be depleted. So how can life on Earth survive?

The decomposer is to decompose the remains of living things, and decompose the organic matter into inorganic matter, so that the inorganic matter will be used by plants, so that the material cycle can be carried out smoothly.