Physiology Essay: The Lymphatic System

They receive signals in order to be activated. One of these signals is a cytokine known as interferon gamma (IFN-γ) secreted mainly by T helper cells. When LDL is deposited, macrophages are activated and the number of MHC class II molecules displayed on their surfaces is increased. When they engulf the LDL, it is broken down and presented to the T helper cells along with the MHC class II molecules for destruction and they are now seen as antigen presenting

Vesicoureteral Reflux (VUR) is the backward flow of urine from the bladder into the kidneys. The muscles of the bladder and ureter along with the pressure of urine in the bladder prevent urine from flowing backward through the ureter. Due to this reason, urine generally flows from the kidneys to the bladder. VUR allows bacteria, which may be present in the urine inside the bladder, to reach the kidneys. This may be lead to kidney infection, scarring and damage.

Perfusion : Perfusion is the process of a body delivering blood to a capillary bed in itsbiological tissue. The word is derived from the French verb "perfuser" meaning to "pour over or through"[3]. Tests verifying that adequate perfusion exists are a part of a patient's assessment process that are performed by medical or emergency personnel. The most common methods include evaluating a body's skin color, temperature, condition and capillary refill. Perfusionists employ artificial blood pumps to propel open-heart surgery patients' blood through their body tissue, replacing the function of the heart while the cardiac surgeon operates.

Epithelial cell migrating across wound usually move along the basal lamina or fibrin deposits, this phenomenon is called contact guidance and is an important factor in epithelial migration. Epithelial migration is followed by increased mitosis of epithelium. Recent evidence suggests that a water soluble heat labile substance called chalcone which is secreted at the wound site is responsible for regulation for mitosis

This can occur through vesicles that are formed by throttling the plasma membrane and then penetrating into the cell (endocytosis), or they merge with it to free their contents (exocytosis) outside. There are three types of endocytosis known: • phagocytosis - very common among unicellular protists, who use it to feed themselves; in the human body, some types of white blood cells incorporate cells and foreign substances into phagocytosis. • pinocytosis - a constant activity of pinocytosis is carried out by the endothelium, the tissue that covers the blood capillaries and which allows the cells of the surrounding tissues to withdraw fluids from the blood. • Receptor-mediated endocytosis - a quick and efficient method for withdrawing substances that can be found in the environment even at low concentrations. Finally, exocytosis is important for the secretion of many substances, including digestive enzymes produced by the pancreas and materials for the construction of the plant cell wall.

Synthesize how might the digestive system and the circulatory system work together? Digested molecules of food, as well as water and minerals from the diet, are absorbed from the cavity of the upper small intestine. Most absorbed materials cross the mucosa into the blood and are carried off in the bloodstream to other parts of the body for storage or further chemical change. As already noted, this part of the process varies with different types of nutrients. 5.

Pharynx The pharynx is the passageway between the mouth and the esophagus and is shared with the respiratory tract. The epiglottis is a cartilaginous flap that closes the opening to the larynx when food is being swallowed down the pharynx. Food is deflected away from the trachea to prevent particle aspiration (inhalation). Esophagus The esophagus is a muscular tube about 25 cm (10 inches) long and pierces the diaphragm on its way to the stomach (Fig. 6-78).

1.3. Oral mucosa 1.3.1. Anatomy and histology The oral mucosa is the mucous membrane lining the inside of the mouth and consists of stratified squamous epithelium termed oral epithelium and an underlying connective tissue termed lamina propria (Nanci and Elsevier, 2013). At the lips the oral mucosa is continuous with the skin, and at pharynx the oral mucosa is continuous with the moist mucosa lining the rest of the gut. thus the oral mucosa is located anatomically between skin and gastrointestinal mucosa (Nanci,2008).

The flow of oxygenated blood to the tissues helps deliver nutrients such as amino acids and electrolytes, water and oxygen. Also, it’s responsible for removing metabolic waste from the cells and disposing of carbon dioxide. The cardiovascular system’s anatomy varies throughout the body and is connected by the arteries, veins, and capillaries. The main organ of the cardiovascular system is the heart. It 's located in the upper torso, chest area, as are some of the body 's major blood vessels.

Connective tissue varies widely in appearance and function, but all forms share three basic components which are extracellular protein fibers, specialized cells, and a fluid known as ground substance. The combination of the extracellular fiber and ground substances produces the matrix that surrounds the cells. The functions of connective tissue are to establish a structural framework for the body. Secondly, it transport fluids and dissolved materials. The connective tissue also protect delicate organ.