Homeostasis is the propensity of an organism/a cell to direct its internal situation, typically by a system of reaction controls, for the health and functioning to be stablelized, despite the outside altering conditions. The capability of the body /a cell is to look for and uphold the state of stability inside its internal environment while it’s dealing with the outside changes. Homeostasis takes place when the body regulates its temperature so as to try maintaining an inner temperature.eg in hot days we sweat to cool off, also we shiver to generate heat in the cold season. Homeostasis use hormones to regulate body conditions. It is extremely significant for the body to survive; because the chemical reactions occurring are easily imbalanced therefore it is essential in observing and controlling the conditions. The examples of homeostasis in human are Acid-Base Balance; the level of acids and bases is regulated by the body, when the level of acidic compounds inside the blood rises, the body acidity also rises.
It occurs when a person produces or consumes extra acidic compounds, as the body fails to get rid of acidic compounds. When the amount of alkaline compounds in the blood rises, body alkaline rises. Acid –Base balance is the equilibrium among acidity and alkalinity within the blood, as per measurement on the pH scale. The lungs, kidneys and buffer systems assist control acid-base balance. The kidney emits extra acids and bases. Kidney damage can decrease the ability of the kidneys to emit the substances causing trouble in acid-base balance. The lungs regulate the PH levels by emitting carbon dioxide. When a person exhales, the diaphragm push carbon dioxide out of the body Changes occurs in the PH of blood when the intensity and speed of breathing change, leading it to adjust to blood ph very fast. Buffer systems help in preventing abrupt change in acidity and alkality.
These systems consist of weak bases and weak acids occurring naturally in the human body. Another example of homeostasis in human is Body Temperature is regulating body temperature. Normal body temperature is around 37 degrees C or 98.6 degrees F. Temperatures that are above or below the normal levels lead to serious complications. Muscle failure and loss of consciousness is caused when the temperatures are below the normal level .When the temperatures are above the normal level the central nervous system start to break down. The body produces heat or release excess heat to control temperature. The third example is the control Glucose concentration; it is the quantity of glucose –blood sugar present in the bloodstream. Body uses glucose as its basis of energy, when there is high level or low level of glucose in the bloodstream it leads to complications. Hormones are used by the body to control glucose concentration. Glucose concentration will be controlled by hormones that are used by the body. Glucose concentration is reduced by insulin, while glucose concentration is increased by glucagon, cortical and catecholamine.
Osmoregulation
It is referred as a physiological process which organism use to uphold water stability by compensating water loss, avoid surplus water gain and sustain the proper osmotic concentration (osmorarity) of the body fluids. Excretion is the removal of toxic (nitrogenous) waste products of metabolism from the body. The waste end products of metabolism contain hydrogen, carbon, oxygen and nitrogen. Carbon atoms are eliminated in carbon dioxide, hydrogen in water (H2O), and oxygen into carbon dioxide and water. Nitrogen is the most toxic end product of protein metabolism and it’s established in high numbers and should be excreted immediately it’s formed. The kidneys carry out detoxification which alters toxic substance into substances that are not poisonous to the body.
The Excretory System
The system of excretory is a scheme of organs and it facilitates the removal waste materials from the body. The cells inside the body break the proteins down in order to fabricate wastes as urea (it is a chemical compound of hydrogen, carbon, oxygen and nitrogen). When cells rupture up carbohydrates (these are compounds including, hydrogen, carbon and oxygen), they generate waste materials such as carbon dioxide and water.
Figure 1: Above is a longitudinal section of the kidney. It has 3 distinct regions i.e. Renal Medulla, Renal Cortex and Renal Pelvis
If these waste products are permitted to build up in the human body, they cause harm to the body's healthiness. The kidneys are considered to be the major organs of excretion in humans; they remove urea, water, and other waste materials from the human body as urine. There are other organism and structures in the human body that are also involved in excretion. The system of respiration gets rid of water mist and carbon dioxide through breath. Through defecation or elimination process undigested solid materials (wastes) and feces are removed from inside the human body by the digestive system. Salts, water and urea are also removed through the skin which is also recognized as a excretion organ.
Kidney Nephrons
Nephrons help take out excess water,wastes and other substances from ones blood. Nephron also returns subsatances like sodium,phosphorus and potassium whenever any of the subsatances run low in the body. Each nephron has a set of blood vessels called glomerulus,which are sorrounded by Bowmans capsule,both of them are known as renal corpsule. Bowman’s capsule connects to membrane-enclosed,u shaped tubule, it empties into a collecting duct. The colecting ducts from a variety of nephrons combine together and eventually empty into the bladder. Glomerulus filters proteins and cells from blood ,all other blood components pass into Bowman’s capsule ,then into the tubule. The U-shaped tubule is used for reabsoption and secretion. Collection Duct gathers all material that has not been returned in the blood by the tubular membranes.
The Structure of Nephrone
Hormones are chemical messenger that go into the blood straight upon their secretion from endocrine glands. One gland or cell can secrete many hormones, and numerous glands are able to secrete the same one hormone. There 3 types of hormones; steroid ego estrogen, peptide e.g. insulin and Tyrosine derivate e.g. thyroxin. Steroid hormone pass directly through the plasma membrane and it straight affect the expression of genes. Peptide hormone is attached to plasma membrane receptor (glycoprotein), it is a receptor and stimulates secondary messenger in cytoplasm which interrupts the action of the cell.
Figure 2: Shows the structure of Nephron
In conclusion osmoregulation is important to plants, animals, humans and fish. In plants osmoregulation is necessary because it controls water ingestion and water loss which is by means of the inner and outer aspects which influence the rate of transpiration. It helps maintain the cell wall tumor and prevent it from collapsing. Certain plants grow by means of water conservation especially those in dry areas and are capable of withstanding prolonged period of water shortage, the plants are known as xerophytes. Other plants have leaves modification to reduce water loss, like the needle formed leaves, waxy cuticles, sunken stomata and thick. For succulent plants like cactus have their water stored in large parenchyma tissues. Osmoregulation is important to body because it helps prevent dehydration so as to assist in the maintenance of water as well as ion for the purpose of balancing the body.
References
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Hughes, M. R. (1989). Progress in avian osmoregulation. the University of California: Leeds Philosophical and Literary Society, .
Kidney Health Care(KHC). (2008, n.d). University of Liverpool. Retrieved may 06, 2012, from The Nephron - Structure and Function of the Nephron : http://www.kidneyhealthcare.com/2010/12/nephron-structure-function-nephron.html
Mallison, W. H. ( Jan 1, 1987). The human side of biology. uk: Harper & Row,.
Toole, G. (Jan 1, 2000). New Understanding Biology for Advanced Level. Nelson Thornes.
