Cilia are microscopic, hair like structures that are found on the surface of most cells. These organelles are divided into two groups: Motile (moving) cilia and non-motile or primary cilia. They were recently discovered about a century ago and initially their purpose was unknown. At first primary cilium were thought to be vestigial organs, but now they prove to be an important part of our bodies (Hoey, Downs & Jacobs, 2012, pg 17-26). Some detect signals from other cells or fluids nearby and are present in organs such as the kidney and eye (Dvorak et al., 2011). Motile cilia have a waving motion and are found in the lungs and respiratory tract to keep the airways clear. Each group of cilia are different in structure and this allows for unique functions. Cilia also has a role in respiratory diseases such as primary ciliary dyskinesia, where cilia contains a defective structure and as a result mucociliary clearance is impaired. There are two groups of cilia, primary and motile cilia which differ in structure and function. The primary cilia is a complex structure with various components such as the ciliary and sub-ciliary compartments. The ciliary compartment consists of a core called an axoneme with nine microtubule doublets that sit around a central core without two central microtubules, commonly known as the ‘9 + 0’ arrangement (Hoey, Downs & Jacobs, 2012, pg 17-26). The core is projected from the basal body and this basal body stems from the mother centriole (Dvorak et al., 2011). The doublets consist of two tubules, one comprising 13 protofilaments known as a complete tubule A, and the other comprising 10 protofilaments known as an incomplete tubule B (Hoey, Downs & Jacobs, 2012, pg 17-26). The microtubule doublets have it... ... middle of paper ... ...primary cilia and motile cilia have varying structures, the most obvious one being that motile cilia have a ‘9+2’ arrangement whilst primary cilia are missing the central pair of microtubules a ‘9+0’ arrangement. Radial spoke proteins and nexin proteins restrict sliding but promote bending in motile cilia, whilst primary cilia are stiff due to the mass of the microtubules being distributed on the circumference. Determining the structure of each type of cilia aids in understanding the role of cilia in respiratory diseases such as PCD. Cilia as discussed is extremely important in our bodies, especially in the respiratory regions as it regulates mucociliary clearance and thus denies pathogens and irritants access to our bodies. However when cilia becomes dysfunctional in various ways, it becomes immotile, and this can cause diseases such as primary ciliary dyskinesia.
Membranes are involved in Cystic Fibrosis when it comes to the genes that are prone to the disease. In a regular functioning body, the CFTR gene helps make the channel that transports charged chloride ions into and out of cell membranes. In a body with cystic fibrosis, the chloride channels don’t function properly, and do not allow chloride ions into and out of the cell membranes, causing the thick mucus (as mentioned earlier) to be produced. The concentration gradients are involved when it comes to moving these molecules and ions across the cell membranes with passive and active transport. Passive transport substances move down concentration gradients while active transport substances move against their concentration gradients (keep in mind this is in a healthy functioning body). With cystic fibrosis, there is a defect in the transport protein, which does not move through the concentration gradient
Healthy lung tissue is predominately soft, elastic connective tissue, designed to slide easily over the thorax with each breath. The lungs are covered with visceral pleura which glide fluidly over the parietal pleura of the thoracic cavity thanks to the serous secretion of pleural fluid (Marieb, 2006, p. 430). During inhalation, the lungs expand with air, similar to filling a balloon. The pliable latex of the balloon allows it to expand, just as the pliability of lungs and their components allows for expansion. During exhalation, the volume of air decrease causing a deflation, similar to letting air out of the balloon. However, unlike a balloon, the paired lungs are not filled with empty spaces; the bronchi enter the lungs and subdivide progressively smaller into bronchioles, a network of conducting passageways leading to the alveoli (Marieb, 2006, p. 433). Alveoli are small air sacs in the respiratory zone. The respiratory zone also consists of bronchioles and alveolar ducts, and is responsible for the exchange of oxygen and carbon dioxide (Marieb, 2006, p. 433).
Each component of this ensemble has a specific function. For example, iris acts as a variable aperture to control the light that enters the eye and ciliary body secretes aqueous humor. The vascular layer is the choroid, which provides blood supply to the retina. The iris arises from the anterior face of the ciliary body and is a forward extension of the choroid. The central aperture in the iris is called the pupil and its size is controlled by the iris to regulate the amount of light that enters the eye. The iris is made up of two types of muscles dilator and sphincter muscles. Sympathetic nervous system innervates dilator muscles and parasympathetic nervous system innervates sphincter muscles. Mydriasis which is dilation of the pupil is a result of increase in dilator muscle activity. Miosis the constriction of the pupil is a result of increase in sphincter muscle activity. The ciliary body consists of smooth muscle, which is innervated by the parasympathetic nervous system. When ciliary muscle contracts, the lens become more convex to accommodate proper vision. The other important function of the ciliary body is the production of aqueous humor, which
Cystic Fibrosis is an inherited disease characterized by the buildup of thick, sticky mucous that can cause severe damage to the body’s organs. Mucous is usually a slippery substance that lubricates and protects the linings of the airway, digestive system, reproductive system and other organs and tissue. Problems with digestion can lead to diarrhea, malnutrition, poor growth, and weight-loss. Due to the abnormally thick mucous it can can clog airways, leading to breathing problems and bacterial infections in the lungs. Bacterial infections can lead to coughing, wheezing and inflammation. Overtime these infections can lead to permanent damage in the lungs including the formation of scar tissue, known as fibrosis and cysts in the lungs (Genetics Home Reference, 2013). The symptoms and signs of this disease vary but mostly include progressive damage to the respiratory system and chronic digestive system problems. An individuals’ lungs who are infected by cystic fibrosis have bacteria from an early stage. This bacteria can spread to the small airways, leading to the formation of bacterial micro-environments known as biofilms. Biofilms are difficult for antibodies to penetrate, therefore the bacteria repeatedly damage the lung and gradually remodel the airways, resulting in difficultly to eradicate the infection (Welsh, 1995). Cystic fibrosis patients may even have their airways chronically colonized be filamentous fungi and/or yeasts. Most men with cystic fibrosis have congenital bilateral absence of the vas deferens (CBAVD), a condition in which the tubes that carry sperm are blocked by mucous and do not develop properly. As well, women may experience complications in pregnancy. Either the c...
Filicide is the intended act of parents killing their children. The act is also regarded as an offence since it amounts to murder. It appears to very unnatural for a parent to end the life of his child. As much as this appears to be inhumane and unimaginable, there are some parents who kill their offspring. Many researchers and scholars have associated these tragedies as being caused by domestic violence among workers and as the extreme result of such domestic violence. According to Jill Proudfoot of the Auckland Safer Homes, the threats are a common happening in relationships and it is the use of such threats that keeps a woman in a given relationship . This means that not all the parents who do this act have mental problems.
This disease is caused by a defective gene and was discovered in the 1930's. Scientists are
When you breathe in, air containing carbon dioxide (CO2) and oxygen (O2) it moves down your trachea; a tunnel containing cartilage and smooth tissue. Air then travels through two hollow tubes called bronchi; narrow branches lined with smooth muscle, mucosal and ringed cartilage to support the structure. The bronchi divide out into smaller tunnels called bronchioles; are small branches 0.5-1mm, lined with muscular walls to help dilate and constrict the airway. At the end of the bronchioles are little air sacs called alveoli; which assist in gas exchange of O2 and CO2. (Eldridge, 2016) Towards the end of alveoli are small blood vessel capillaries. O2 is moved through the blood stream through theses small blood vessels (capillaries) at the end of the alveoli and the CO2 is then exhaled. (RolandMedically,
Person, A. & Mintz, M., (2006), Anatomy and Physiology of the Respiratory Tract, Disorders of the Respiratory Tract, pp. 11-17, New Jersey: Human Press Inc.
parts to it; the choroids, ciliary body, and the iris. The choroids is what provides
The cytoskeleton is a highly dynamic intracellular platform constituted by a three-dimensional network of proteins responsible for key cellular roles as structure and shape, cell growth and development, and offering to the cell with "motility" that being the ability of the entire cell to move and for material to be moved within the cell in a regulated fashion (vesicle trafficking)’, (intechopen 2017). The cytoskeleton is made of microtubules, filaments, and fibres - they give the cytoplasm physical support. Michael Kent, (2000) describes the cytoskeleton as the ‘internal framework’, this is because it shapes the cell and provides support to cellular extensions – such as microvilli. In some cells it is used in intracellular transport. Since the shape of the cell is constantly changing, the microtubules will also change, they will readjust and reassemble to fit the needs of the cell.
Chronic bronchitis is a disorder that causes inflammation to the airway, mainly the bronchial tubules. It produces a chronic cough that lasts three consecutive months for more than two successive years (Vijayan,2013). Chronic Bronchitis is a member of the COPD family and is prominently seen in cigarette smokers. Other factors such as air pollutants, Asbestos, and working in coal mines contributes to inflammation. Once the irritant comes in contact with the mucosa of the bronchi it alters the composition causing hyperplasia of the glands and producing excessive sputum (Viayan,2013). Goblet cells also enlarge to contribute to the excessive secretion of sputum. This effects the cilia that carry out the mechanism of trapping foreign bodies to allow it to be expelled in the sputum, which are now damaged by the irritant making it impossible for the person to clear their airway. Since the mechanism of airway clearance is ineffective, the secretion builds up a thickened wall of the bronchioles causing constriction and increasing the work of breathing. The excessive build up of mucous could set up pneumonia. The alveoli are also damaged enabling the macrophages to eliminate bacteria putting the patient at risk for acquiring an infection.
In Shakespeare’s Julius Caesar, Caesar’s potential to rise to dictatorship threatens the Roman Republic, therefore people from the Senate conspire against Caesar and kill him to save Rome. But Rome cascades into chaos, and Brutus and Antony go to war, which ends with the death of more people. The plot of the play sparked a discussion question that was asked in class; the question is: who is innocent and who is to blame? I thought about this question while watching I, Cinna (The Poet). Caesar, Brutus, and Cassius were the three predominant characters the class argued about, but none of them are innocent and they all bear some responsibility in Caesar’s murder. Cinna, the poet, is the only character who is killed for doing absolutely nothing;
Lastly there’s the vacuole. The vacuole is a closed compartment that’s stores and keeps water inside of the cell. It sometime carries solids that have been engulfed. Vacuoles are formed by fusions of multiple membrane vesicles. They are found in both plant and animal cells, but appear larger in plant cells. Vacuoles have no key shape or size. Its size and shape is based on the need of the cell. The vacuole does more than just store water, it separates materials that can harm the cell, holds waste and small molecules and passes on unwanted
Dynamic equilibrium functions in the three semicircular ducts, the saccule and the utricle. The two ventical ducts are the anterior and posterior semicircular ducts. The lateral semicircular duct is horizontal. In the dilated portion of each duct, the ampulla, is a small elevation called the crista. This contains hair cells and supporting cells which are also covered by a mass of gelatinous material which is called cupula. When the head moves the attached semicircular ducts and hair cells move with it.