2. How does exercise affect diabetes mellitus?
During exercise, the whole-body oxygen consumption usually increases 20-fold. However, greater increases have been reported in the working muscles (American Diabetes Association). Under such circumstances, the skeletal muscles increase the utilization of stored triglycerides and glycogen, as well as the free fatty acids. Consequently, exercise maintains appropriate glucose levels in order to preserve the function of the central nervous system. In patients with diabetes mellitus, therefore, exercise ameliorates insulin sensitivity and helps to lower the elevated levels of blood glucose to the normal range (American Diabetes Association).
3. How does the structure of hemoglobin allow it to combine with
oxygen?
A hemoglobin molecule comprises of four polypeptide chains with each chain containing a heme group. The heme group has one iron ion that forms the site for oxygen binding. Each metal ion binds one molecule of oxygen; hence, a hemoglobin molecule can binds four oxygen molecules. Each of the heme units holds the metal ion in a position that allows interaction with oxygen molecules. Thus, the interaction leads to the formation of oxyhemoglobin.
4. Define the term Positive chemotaxis
Chemotaxis involves the movement of bacteria or somatic cells in response to particular chemicals in their surroundings. The phenomenon allows bacteria to move towards a high food concentration or to avoid the concentrations of poisons such as phenols. A positive chemotaxis occurs when the cell movement is directed towards a higher concentration of a particular chemical.
7. What is meant by cardiac cycle?
The cardiac cycle describes the sequence of occurrences during a heartbeat. The cycle involves two phases: diastole and systole. In diastole, the heart ventricles become relaxed, hence, allow the heart to fill with blood. In systole, however, the ventricles undergo contraction and, therefore, pump blood into the arteries. A complete cardiac cycle involves the filling of the heart with blood and the pumping of blood into the arteries.
11. Discuss the function of the thymus
The thymus is the lymphatic system’s primary gland that occurs behind the sternum. The lymphoid gland comprises of two equal lobes. The thymus gland controls the immune system by developing specific cells that promote the cell-mediated immunity. Moreover, the gland produces various hormones that enhance the growth, as well as maturation of cells. Further, the thymic hormones alter endocrine system’s structures, such as the adrenal glands, and promote sexual development.
12. Define the term innate immunity
Innate immunity occurs naturally and is not stimulated by the prior sensitization to antigen that results from infections or vaccination. The immunity is nonspecific because it is not induced by specific antigens. Its response depends on phagocytic cells and proteins that become activated in the presence of pathogens and, hence, destroy the invaders.
13. What are the monoclonal antibodies, and how do they function?
Monoclonal antibodies are made in biological laboratories and comprise of one type of antibodies. They recognize and adhere to particular cellular proteins. Each of the monoclonal antibodies binds to one specific protein. Hence, the antibodies function in various ways depending on the targeted protein. Researchers make different monoclonal antibodies in order to target, for example, the various forms of cancer.
18. Describe the seven functions of the stomach
The stomach provides a temporary storage of food. Thus, it allows time for the digestive enzymes to act on the food material. Secondly, it promotes the digestion of food. For example, it releases proteases, which digests proteins, and hydrochloric acid that provides the low pH required for the functions of proteases. Thirdly, the stomach provides limited absorption of substances such as alcohol, fat-soluble drugs, and water. The absorption of such substances occurs across the stomach’s lining. Fourthly, it forms the site for mechanical breakdown, as well as chime production. It helps to turn food into a semi-liquid substance and, hence, promotes the absorption of nutrients. The fifth function is that it helps to destroy microorganisms in the food. The hydrochloric acid, for example, contributes in the killing of various pathogens. The sixth function is that it regulates the movement of food into the duodenum and, thus, into the small intestine. The regulation reduces the amount of food in the intestine, which increases the surface area for the absorption of nutrients. The seventh function is that it produces an intrinsic factor that promotes the assimilation of vitamin B12. The Intrinsic Factor is produced by the stomach’s parietal cells.
19. What is believed to be the function of the vermiform appendix?
The vermiform appendix was once viewed as an evolutionary remnant that had little physiological significance. However, recent research shows that it has a significant mucosal immune function (Zahid). In particular, it is linked to the extrathymically derived T-lymphocytes, as well as the B-lymphocyte-mediated responses. In addition, it allows the efficient movement and removal of wastes from the digestive system. Moreover, it has lymphatic vessels, which control pathogens in the digestive system (Zahid).
20. What is pyloric stenosis?
Pyloric stenosis is a rare medical condition that affects the pylorus or the opening between the small intestine and the stomach in infants. In the condition, the pylorus muscles become thick and, hence, prevent food from reaching the small intestine. It leads to forceful vomiting, weight loss, and dehydration. Surgery is, usually, recommended in order to fix the problem (Mayo Clinic Staff).
Works Cited
American Diabetes Association. “Diabetes Mellitus and Exercise.” Diabetes Care, 25, 2002: n. pg. Web. 6 Dec. 2014.
Mayo Clinic Staff. Pyloric Stenosis. Mayo Clinic, 16 Nov. 2012. Web. 6 Dec. 2014
Zahid, A. “The vermiform appendix: not a useless organ.” J Coll Physicians Surg Pak, 14.4, 2004:256-258. Web. 6 Dec. 2014.
