Homeostasis refers to the ability of an organism or environment to maintain stability. Often produced by an innate ability to maintain homeostasis would be the ability to regulate bodily temperatures Communication between the bodily systems is key for maintaining stability and therefore homeostasis. The human body contains multiple systems which when working together are able to create a strong sense of stability for everyday bodily functions, however each of these systems are able to contract region specific pathologies which can begin to cause problems for said system that may be affected but also for the linking systems as many of the body systems can depend on each other for the security of homeostasis. The systems in the body consist of: The Respiratory system, the Cardiovascular system, the Digestive system and the Renal (urinary) system.
Although each system is vital for the body, one system in particular can be seen as the centre of all body systems; the Cardiovascular system. The cardiovascular system consists of the heart, veins, blood vessels and blood. The key organ within the cardiovascular system is the heart. The heart is often known as a hydraulic pump for circulation of the rest of the body. The average mass of an adult heart is around 275g and is the size of a clenched fist. The heart contains a dual pump system which contributes to various forms of circulation and also targets specific parts of the heart. In the heart there are 4 chambers, the left/right ventricle and the left/right atrium, a dual pump system within allows the heart to collect deoxygenated blood from the right side whilst also collecting oxygenated blood from the left side via the pulmonary vein, this bodies then sent out and around the body via the aorta. This is a strong promotion of homeostasis as this allows for regular circulation to the rest of the body particularly the digestive and respiratory systems. The 4 chambers of the heart are also vital as the they contain valves which are able to prevent the potential back flow of blood that may travel back in to the heart from the veins. This also certifies the travelling of blood to the required organs. The Cardiovascular system also contains many blood vessels, the blood vessels are what carry the blood around the body to various organs and muscles.
Although able to promote homeostasis around the body, the cardiovascular system can also be quite susceptible to certain diseases and pathologies that may affect the effectiveness and functionality of the various organs. One pathology in particular would be high blood pressure. The effects of high blood pressure in any person can be very aggressive and if untreated can lead to fatal diseases such as Coronary Heart Disease (CHD) or kidney failure. Also known as hypertension, high blood pressure is a result of the systolic reading of a persons blood pressure consistently exceeds 160mmHg, or if the diastolic pressure exceeds 95mmHg. There are many factors that can contribute to the chances a person may begin to suffer from high blood pressure, age, obesity, inherited factors can all be considered. The primary cause of high blood pressure issue to a result of peripheral resistance and reduced elasticity of blood vessels resulting in gradual narrowing. The left ventricle can enlarge significantly to attempt to maintain output. Common and non-drug related treatments for high blood pressure are often suggestions of weight loss, salt restriction and increased exercise. However medicated responses are anti-hypersensitive drugs for example beta-blockers also known a b- adrenoceptor antagonists.
Another body system would be the respiratory system. Homeostasis in particular is mainly due to the respiratory system regulating gas exchange and blood pH levels. Gas exchange in the respiration system consists of the primary function to exchange Oxygen and Carbon Dioxide. Once inhaled, oxygen enters the lungs and the alveoli. The alveoli and surrounding capillaries have layers of cells that are one cell thick. This allows for very close contact of the alveoli and capillaries. Oxygen is then able to pass though the barrier into the capillaries and into the blood. The oxygenated blood then travels to the heart via the pulmonary vein and to the rest of the body, meanwhile carbon dioxide has passed through the blood and into the alveoli to be exhaled and expelled from the body. Within the respiratory system there are also two types of respiration; external and cellular. External respiration is the change of O2 and CO2 in the body to maintain oxygen levels within the lungs and blood. Cellular respiration is the process of respiration that includes the use of glucose (C6H12O6) to produce ATP for the body to then use as its energy source, this also contributes to the regulation of glucose levels in the body.
C6H12O6 + 6O2 = 6CO2 = 6H20 = ATP (Adenosine Triphosphate)
This formula shows how the respiratory system is able to take the current levels in the body transform it into the needed products of ATP and o2, whilst leaving a waste product of 6CO2 which is then expelled from the body during exhale. The main components of the respiratory system are: the nose, the pharynx, larynx, trachea, bronchi and the lungs. Within the lungs are alveoli which are surrounded by capillaries. CO2 is able to diffuse into the alveoli, this is due to the alveoli and pulmonary walls being only one cell thick, therefore the two cell thick layers are facilitated quite easily and rapidly for diffusion and gas exchange.
One way in particular the respiratory system can affect the stability of homeostasis would be due to certain diseases and infections. One disease for example would be Cystic fibrosis. Cystic Fibrosis is the presence of excessive music lining the small intestinal tract that can interfere with absorption causing malnutrition. often, this music is manually expelled from the body via violent coughing. The excess mucus is made up of proteases and antiproteases, antibiotics, antibodies and antioxidants that are working together and against each other to destroy pathogens whilst trying to avoid any extensive damage to the lungs.This illness can affect 1:1500 people, and is an inherited autosomal recessive fashion. The odds of survival have increased with the expected age surpassing age 30, this is particularly due to advances in diagnosis, diagnosis, treatment procedures and nutrition. One of the more dependent and trusted ways of diagnosis Cystic Fibrosis is through a sweat test. The sweat test is able to determine if there are elevated levels of sodium and chloride within the body. As this can be quite an aggressive disorder ranging from person to person, there are multiple treatments that may have different effects on the severity of the disorder. One treatment in particular is ‘Enzyme Therapy’. Enzyme therapy of the pancreatic enzyme, this entails the replacement of enzymes to correct maldigestion. Microspheres are also used to relive enzymes in the duodenum to digest proteins, fats and carbohydrates.
The digestive system in the body is able to promote homeostasis due to the breakdown of large food molecules and promoting absorption. In particular the digestive promotes homeostasis by providing the body with the retired nutrients, minerals and vitamins for daily bodily functions. The digestive system in composed of: the stomach, the large and small intestine, gallbladder, liver, pancreas and the anus. The south contains the buccal cavity which contains the salivary glands, tongue and teeth. The salivary glands create saliva to help lubricate and move food down the oesophagus. Peristalsis takes place during the movement of food, this process is the contractions of the oesophagus muscles to revert food from travelling back up the oesophagus. The food is then throughly mixed in the stomach by gastric muscles. The food is broken down via hydrochloric acid secreted into the stomach via the liver and gallbladder. This also included the secretion of bile salts, that are composed and secreted in the liver and stored in the gallbladder. The primary digestion and absorption occurs in the small intestine, the large intestine is then able to reabsorb water and facilitate the excretions of waste materials. Also an often surpassed function oft he digestive system would be the bacteria located in the gut. This particular bacteria influences the immunity in the large and small intestines and is also found to influence the systemic immunity of the body. Lymph nodules located in the lining of the ‘gut’ secrete cytokine synthesis inhibitory factor (CSIF) that is an anti-inflammatory and also has been proven to decrease the likely spreading of tumours in the Gastrointestinal tract. The digestive system is also known to provide immune cells known as ’T cells’ these particular cells are known as helper cells as they are sub-categorised into 4 separate categories, they are each able to regulate the balance within the body that is crucial to overall health.
One disorder of the digestive system in particular is Coeliac disease. This disease is contracted due to the T-cell response to ingested gluten, particularly by people who are genetically predisposed. The onset of Coeliac disease is usually from infancy to young adulthood, as this is when symptoms will often begin to occur and show. The reaction to the gluten refers to the specific peptide fractions of proteins specifically in such foods as wheat, rye and barley. There are certain consequences to the effects of coeliac disease, for example the immune reaction to gluten can cause changes in the intestinal mucosa. This results in the affected areas, such as the absorptive surface area becoming flat and shortening, or the absence of microvilli in overdeveloped crypts. There are chances the damager may be restated to certain areas, e.g. the duodenum, this therefore correlates to the degree of malabsorption which will then depend on the severity of damage caused. This malabsorption can relate to the inability to absorb specific nutrients such as macronutrients, fat-soluble vitamins, electrolytes and B12. There are also many cases in which there is a correlation to suffering from anaemia. Physical and notable symptoms for Coeliac disease would be signs such as being noticeably under weight, there can also be the possible symptoms of dermatitis herpetiformis, a sever and rash on the skin. As Coeliac disease is a lifelong disease, it is often treated with a lifelong gluten free diet, this particular diet supplements the vitamins and minerals that may be naturally malabsorbed. Foods such as rice bread, corn flour, any dairy products and meats are promoted for a beneficial diet whereas foods such as bread, pasta, cakes and biscuits are not.
The renal system is able to promote homeostasis as the main organs of the renal system are the kidneys, the kidneys in particular are able to maintain the acid base balance and the water and sodium levels in the blood. The other components of the renal system are; the the bladder, ureters and the urethra. The structure of the kidneys contains an outer cortex and the inner medulla. The blood enters the kidneys from the renal arteries and is passed via the renal vein. Each kidney contains millions of nephrons, nephrons promote filtration, particularly in the corpuscle. The fluid produced enters the tubules and is modified though reabsorption and secretions flow through. For the blood, it s entered into the smaller arteriole cortex of the kidney from the renal artery. Each arteriole splits into a structure known as the glomerulus. the blood is taken into the glomerulus by the afferent arterioles and is expelled by the efferent arterioles. This filtration takes place to allow the body to expel any excess fluids, this filtration does not allow larger molecules such as proteins to pass through therefore only allowing smaller molecules to pass into the renal tubule. The proximal convoluted tubule (PCT) contains many microvilli that will help aid reabsorption of any useful substances. fluid then passes from the PCT and into the Loop of Henle. the Loop of Henle’s primary role is to reabsorb water and sodium from the fluid filtrate. The fluid then enters the Distal convoluted tubule where selective reabsorption’s and secretions of Potassium(K+), Sodium (Na+) and Chloride(Cl-) takes place. The collecting ducts receives the final product of the filtered fluids, water(H20) is able to leave the collecting ducts via osmosis. The permeability of the water is due to the effects of the Anti-Diuretic Hormone (ADH). This hormone is released due to the concentration of water in the blood and if it should decrease.
Chronic Kidney Disease (CKD) is a longterm condition and develops of a long period of time. Tis particular disease is irreversible and progressive. There are also 5 stages to CKD, each ore aggressive than the last. In CKD the kidneys do not work effectively. CKD does not usually have notable symptoms until it has advanced to a more aggressive stage. Symptoms such as tiredness, nausea, swollen feet/ankles or blood in the urine can begin to occur. As with many disease some people may be more at risk than others, some people in particular would be people who may suffer from diabetes, high blood pressure, and in people ages 60+. This factors can be at increased risk as the preventions and treatments to CKD are often diet related therefore linking also to diabetes and high blood pressure. The consequences of suffering from CKD can lead to problems such as fluid and sodium retention, mineral and bone disorders and also anaemia. For stages 1-3 of CKD management and treatment often includes the reduction of any possible cardiovascular risk factors, whereas for stages 4/5 management and treatment is much more complex and vital. Often several dietary factors may need to be considered e.g. supplementary foods/drinks. Particular substances such as sodium, potassium and phosphorous are the most monitored and moderated as increased amounts of said substances can begin to create multiple consequences for CKD suffers, consequences such as Hypertension, Hyperkalaemia and Hyperphosphatemia. This can then require these particular substances to be significantly decreased or eliminated for a diet completely.