I have discovered about the various structure in the respiratory system. The respiratory tract is divided into 2 main segments: Upper respiratory tract and lower respiratory tract. The upper respiratory tract includes nose, nasal cavity, sinuses and pharynx while the lower respiratory tract includes larynx, trachea, bronchi and lungs.
Also, I have understood more about how the structure of each part of the respiratory system helps to ensure us to respire smoothly and how the inhaling and exhaling of air takes place. During inhalation, the external intercoastal muscle contract and the internal intercoastal muscle relax. Diaphragm will contract and flattens, ribs will move up and out.
This will result in the volume of thorax increases and the intrapulmonary pressure to be lower than the atmospheric pressure. Air will move from the higher pressure which is the atmosphere to the lower pressure which is the lungs. The air inhaled will enter through the nose and into the nasal cavity. The nasal cavity is line with hair and mucous membrane.
The hair and mucous in the nasal cavity will help to trap any dust particles or any contaminants that is found in the air. Also, the nasal cavity will also moisturize and warm the air to body temperature. This is also part of maintain the thermoregulation, this is to prevent the air inhaled from affecting the temperature of the body. The air inhaled in will then move to the sinuses.
Sinuses will help to moisturize and trap foreign particles. Then, the air will move to the pharynx. Pharynx helps to connect the nasal cavity to the larynx and oesophagus. Following, the air inhaled will go through the larynx, larynx will connect pharynx into the trachea.
Then, the inhaled air will move into the trachea. Trachea helps to provide a clear airway for air to enter or exit the lungs. This is done by the presence of the pseudostratified columnar epithelium. The goblet cells that are found on the epithelium will secrete mucous to trap foreign bodies while the cilia found on the epithelium will sweep the foreign particles upwards out of the respiratory tract.
The trachea will then divide into 2 primary bronchi; the left branches and the right branches. The primary bronchi will run into the lungs and will be divided into secondary bronchi, then divide into tertiary bronchi. The tertiary branches will then further branch out to form terminal bronchiole. Terminal bronchiole will branch to form respiratory bronchiole and lastly form the alveolar duct. Alveolar duct will spilt into many alveolar sacs and last spilt to form alveoli. At the alveoli, it is where the external respiration will take place where there will be an exchange of gases between the alveoli and the blood capillaries. The air that enters the lungs has a higher partial pressure of O2 and a lower partial pressure of CO2. Due to the difference in the pressure, oxygen will diffuse across the simple squamous epithelium into the blood capillaries.
Oxygen will combine with haemoglobin in the red blood cells to form oxyhaemoglobin. Then, it will be transported through the blood vessels to other parts of the body. Carbon dioxide will then diffuse into the alveoli and is remove from the lungsInternal respiration is the exchange of the blood in capillaries and the tissues of the body. The capillary blood in this case will have higher partial pressure of oxygen and lower partial pressure of carbon dioxide than the tissues. This will result in the oxygen entering the tissue while the carbon dioxide leaves the tissue and enters the capillaries. In the capillaries, the carbon dioxide will react with water to form carbonic acid and this is catalysed by carbonic anhydrase. To prevent carbonic acid from altering the pH, carbonic acid will be further converted into bicarbonate ions. Bicarbonate ions is then transported back to lungs and are remove out of the body.
During exhalation, the internal intercoastal muscle contract while the external intercoastal muscle relax. Diaphragm will relax and domes upwards. This result in the ribs to move down and inwards. Volume of thorax will decrease, and the intrapulmonary pressure will be higher than the atmospheric pressure.
As a result, the air will rush out of the lungsI also find out that it is very important for respiratory system to work as the respiratory system helps in gas exchange where oxygen is taken into the body while carbon dioxide is remove from the body. Without the respiratory system, oxygen cannot take in and aerobic respiration cannot take place. This will consequently result in the inability to break down to glucose into ATP through the biochemical pathway due to the absence of oxygen.
Also, if carbon dioxide is not remove in the body, it will lead to accumulation of CO2 in the body and thereby causing the altering of pH. The altering of pH in the body will lead to severe consequence where some of the organ in the body are unable to function normally. For example, the small intestine should have a slightly alkaline pH, the change in pH, might cause the enzyme to unable to function causing the nutrients unable to breakdown properly.