Respiratory organs in lower organisms

Respiration is an oxidation process that involves the decomposition of a complex organic substance, resulting in the production of carbon dioxide, water, and energy. The process of breathing can be separated into two stages:

External Respiration or Breathing

Animals take in oxygen and emit carbon dioxide throughout this process. Breathing is another name for it. There are primarily two parts to this.

• Inspiration is the process of delivering oxygen to the lungs.

• Expiration is the process through which carbon dioxide is released from the respiratory organs into the atmosphere.

Respiratory system

In living organisms, the mechanism that takes in oxygen and releases carbon dioxide to meet energy demands. The oxidation of carbon-containing compounds in a living body releases energy as well as carbon dioxide. Respiration is the exchange of respiratory gases (oxygen and carbon dioxide) between the organism and its environment, as well as between the cells of the body and the tissue fluid that bathes them.

Direct Diffusion

Diffusion via the outer membrane is adequate to supply the oxygen needs of tiny multicellular organisms. For organisms with a diameter of less than 1 mm, direct diffusion across surface membranes is an efficient method of gas exchange. Every cell in the bodies of simple creatures like cnidarians and flatworms is in close proximity to the outside world. Gases diffuse swiftly through direct diffusion because their cells are maintained wet. Flatworms are small, flat worms that ‘breathe’ by diffusing through their outer membrane. The flat shape of these organisms increases the accessible surface area for diffusion, ensuring that each cell within the body is close to the outer membrane surface and has access to oxygen. The cells in the core of the flatworm’s body would not be able to get oxygen if it had a cylindrical body.

Types of Respiratory system in animals

Skin, Gills, and Tracheal systems

Animals breathe through a number of organs, including their skin, gills, and tracheal systems.

Skin and Gills

Animals use a number of gas exchange systems. In mammals, air is taken in from the outside environment and delivered to the lungs. For example, earthworms and amphibians use their skin (integument) as a respiratory organ. A rich network of capillaries just beneath the epidermis allows gas exchange between the external world and the circulatory system. The respiratory surface must be kept wet to allow gases to dissolve and diffuse through the cell membrane.

Water-dwelling species, too, require a way to obtain oxygen. Water dissolved oxygen, but only in a little amount compared to the atmosphere, which contains roughly 21% oxygen. Fish and many other aquatic organisms have evolved gills to aid in the absorption of dissolved oxygen from the water. Gills are thin tissue filaments that are extremely branched and folded. When water flows over the gills, the dissolved oxygen in the water rapidly diffuses through them and into the bloodstream. The circulatory system subsequently transports the oxygenated blood to various regions of the body. In animals that have coelomic fluid instead of blood, oxygen diffuses over the gill surfaces into the coelomic fluid.           

Tracheal systems

Because an insect’s respiratory system is separate from its circulatory system, blood does not play a direct role in oxygen transfer. The tracheal system is a highly sophisticated type of respiratory system seen in insects, consisting of a network of small tubes that deliver oxygen throughout the body. The tracheal system, which is the most direct and effective breathing pathway in active animals, contains tubes made of a polymeric material called chitin.

Amphibian and Bird Respiratory systems

Birds and amphibians require different amounts of oxygen than mammals, which necessitates different respiratory systems.

Amphibian Respiration

Amphibians have developed a variety of breathing techniques. Young amphibians, such as tadpoles, breathe through their gills and do not leave the water. The gills dissolve as the tadpole matures, and the lungs expand (though some amphibians retain gills for life). These lungs are rudimentary and do not have the same level of evolution as mammalian lungs. Because adult amphibians lack or have a limited diaphragm, they must breathe through their lungs. Diffusion across the skin is another way for amphibians to breathe. Amphibian skin must be kept wet to assist dispersion. It has vascular tissues that allow for gaseous exchange. On land, this moist skin interaction can be a hindrance, but it works wonders underwater.

Through plasma Membrane

Gas exchange occurs through the cell surface in unicellular creatures like amoeba. They take in oxygen from the air or water around them and release carbon dioxide by diffusion through the plasma membrane.                            

Mammalian Respiratory system

When air enters the body through the nasal cavity, pulmonary ventilation occurs in mammals. As it passes through the nasal canal, the air is warmed to body temperature and humidified. To protect the tissues from direct contact with air, the respiratory system is covered with mucus that is rich in water. Water is picked up by air as it passes over the mucous membranes. This balances the air supply to the body, minimising the harm that cold, dry air can inflict. In the nasal passageways, particulates in the air are also eliminated. These are all defensive mechanisms that safeguard the trachea and lungs from harm. Air travels from the nasal cavity to the trachea via the pharynx and larynx. The trachea’s job is to transport breathed air to the lungs and exhaled air out of the body. The human trachea is a cylinder that runs from the larynx into the chest cavity and is about 10-12cm long and 2cm in diameter. It divides the two major bronchi at the mid thorax and is made up of incomplete rings of hyaline cartilage and smooth muscle. Mucus-producing goblet cells and ciliated epithelia line the trachea, propelling foreign particles caught in mucus toward the pharynx.                                          

Conclusion

The page contains all of the critical information that a student needs to know about the Respiratory organs in lower organisms at a basic level, such as its types and parts, among other things. This is a vital piece of equipment for taking Respiratory organs in lower organisms.