Differences in the Anatomy and Physiology of Persons Who Moved From Lower Altitudes - Term Paper Example

Differences in the anatomy and physiology of persons who moved from lower altitudes to become acclimated to higher altitudes Institution: Instructors name: Course name: Date due: Introduction A high altitude is 2400m above sea level and look at case studies of people such as the Andeans in South America, the Tibetans along Himalayan Mountains and Peru. They have over the years adapted to living in environments with low oxygen and cold. These people have adapted physiologically and anatomically to factors like reduction in heart diseases, changes in the body mechanism and coronary diseases. Though, they suffer from chronic mountain sickness and pulmonary hypertension. This paper will examine the effects of high altitude on the anatomy and physiology of people who move from a low altitude to live in high altitudes areas. Physiological adaptations Physiological adaptations are short term adaptations brought by rapid change in environment to the body. Such as the sweat glands will sweat when the body moves to a hot environment. Where the body is adapted to a hot environment, and the body is always warm, there is a relative selective pressure on the sweat glands. This means that the body can only sweat when temperatures exceed the normal range. There are responses to physiological adaptations which are primary and secondary adaptations to common stressors such as heat, cold, altitude, sunlight disease and malnutrition that come in excess (Sutton & Anderson, 2010). Acclimatization or primary responses take a minute or days as they are immediate. They include changes in respiration, sweating metabolism and blood distribution. The secondary responses may take months or years such as the abilities of a person to work, population distribution and changes in fertility. One of the experiences people have when they move from a low to a high altitude area is that they have oxygen deprivation or hypoxia. Hypoxia is when the person experiences low atmospheric pressure in the lungs making it hard to pass through oxygen. The lungs of people from low altitude areas are small, and they are deprived of sufficient oxygen in high altitude areas. This person can suffer from high blood pressure, increased heart rate, respiration and dilation of blood vessels. The most efficient response is the secondary response, where there will be an expansion of the vascular networks increase in mitochondria and production of the red blood cells to counter low oxygen supply (Sutton & Anderson, 2010). At high altitudes, low oxygen supply affects the work ability of people as it tends to decrease, and they become slow. At this oxygen levels, miscarriages are experienced in women, and other women tend to move to lower altitudes with sufficient oxygen to give birth or procreate. Some cultures such as Andes in South America have adapted to this high altitude and low oxygen by mitigating the effect with the use of drugs such as cocoa leaves. Other physiological adaptations to cold are the increased intake of calories which increases the metabolism rate and burns energy at a higher rate. Also, heat loss in the body can be reduced, and tissues kept alive when there are variations in blood flow to exposed skin surfaces. Fire, clothing, and alcohol can be used to mitigate cold for a short time (Sutton & Anderson, 2010). Menarche is the first menstrual cycle bleeding that occurs in girls. Environmental factors interact with genetic factors to determine the age of sexual maturation especially in puberty. High or low altitude can influence the timing of menarche especially when other body structures developments are happening. In high altitudes, the menarche is later than in lower altitude areas where it is faster. Some menstrual cycle begins earlier or later than other in teens, which is usually between the ages of 11-15 years old (Crooks & Baur, 2013). Other factors that influence menarche are heredity, general health, social and physical environment (Crooks & Baur, 2013). Anatomical adaptations Anatomical adaptations involve long-term changes in genetics such as the genotype brought by the selective pressures. In the long term people who move to high altitude area from low altitude can pass changes to their next generations. Changes such as large lungs with several generations will out-compete the ones with smaller lung. With time, they will become the dominant phenotype. Larger lungs adapt to extraction of more oxygen from the large amount of air during respiration. Also, the body structure will change such as increase or decrease of the body surface area to regulate temperatures. For instance, a rounder and a shorter person have a lesser surface area for heat to escape in a cold environment (Sutton & Anderson, 2010). Both physiological and anatomical adaptations The heart at high altitude is prone cardiovascular stress resulting in the increase of cardiac output and transient blood pressure rise with no fraction ejection. People who live in high altitude have adapted to chronic hypoxia. Although there is less supply of oxygen in the high altitude areas as compared to the low altitude areas, myocardium postulates a better oxygen extraction without traces of anaerobic metabolism. This increases oxygen release at the tissue level. Pulmonary vascular resistance can be triggered by hypoxia causing an increase in the number of smooth muscles in the pulmonary veins. A case study done at high altitudes 4300m above sea level in the Andean highlanders showed that there is a low prevalence of high blood pressure. In comparison with Andeas, Tibetan study done showed that the high blood pressure prevalence is similar to people living at sea level. At low attitude, hypertension is associated with risk factors for classical cardiovascular and obesity while hyperuricemia frequency correlates with high altitudes (Hurtado, Escudero, Pando, Sharma & Johnson, 2012). Among the Andeans living at high altitudes, there was a low prevalence of coronary heart disease in comparison with people living in low altitude areas. Also, stroke and heart diseases mortality decreased. This was as result of molecular change by hypoxia that has a cardioprotective effect. An elevation in the production of vascular endothelial growth factor by hypoxia results in the increase of coronary vasculature branches of people living in the high altitudes. This increases oxygen extraction and more consideration of glucose to fatty acids. Some of the major factors that cause ischemic heart disease such as obesity and diabetes are lower in high altitude areas than low altitude areas. This reduction in coronary heart disease is enhanced by the effects of high altitude on pulmonary hypertension (Hurtado et al., 2012). The kidney is also affected by high and low attitudes in its functionality. There is a significant reduction of the renal plasma flow for Highlanders than lowlanders. This is as a result of hematocrit elevation and which is in line with the preservation of glomerular filtration rate due to an increase of filtration fraction. There is a high prevalence of hyperuricemia and hypertension in people living in high altitude areas. In Peru a study showed that people had an increase in uric acid due to a rise in hematocrit and were found to be with people in high altitude with coronary mountain sickness than people while live in lower altitudes (Hurtado et al, 2012). In conclusion, people living in high altitude areas under hypoxic condition have both advantages and disadvantages on their health. This has brought about other people developing some protective mechanisms against certain diseases that are as a result of low oxygen and cold environment. The Andeans have lived in those conditions for a long time and have adapted to the effects of chronic hypoxia. Coronary heart disease, diabetes, and obesity have shown a reduction in Highlander, and they are more prone to increased pulmonary and systemic hypertension (Hurtado et al., 2012). References Crooks, R., & Baur, K. (2013). Our sexuality. Cengage Learning. Hurtado, A., Escudero, E., Pando, J., Sharma, S., & Johnson, R. J. (2012). Cardiovascular and renal effects of chronic exposure to high altitude. Nephrology Dialysis Transplantation, 27 (suppl 4), iv11-iv16. www.ncbi.nlm.nih.gov/... National Center for Biotechnology Information Sutton, M. Q., & Anderson, E. N. (2010). Introduction to cultural ecology. Lanham, Md: AltaMira Press Read More