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Biochemical role of vitamin a
Biochemical role of vitamin a
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Vitamin A is a fat-soluble nutrient. It plays an important role in vision, maintenance of epithelial cells, immune functions, and participates in the processes of growth, development and reproduction. Vitamin A is characterized into two chemically distinct yet structurally related forms. The first form is retinoid, which is present only in foods of animal origin, such as fish and organ meats. “Retinoid is also known as 'preformed vitamin A' because it can be metabolized directly into compounds that exert the biological effects of vitamin A” (Ross, 2005, p. 329). Preformed vitamin A retinoids are found in liver, fish, fish oils and eggs. A second form of vitamin A is β-carotene, which is synthesized only by plants, but can be turned into vitamin A in the body as needed. These carotenoids are also termed as 'provitamin A.' Provitamin A caretinoids are mainly found in carrots, spinach, broccoli, sweet potatoes, apricots and mangoes. Hence, the nutritional requirements for vitamin A can be met by retinoids, carotenoids, or a mixture of both from plant and animal sources. However, deficiency and excessive intake of vitamin A could lead to serious consequences.
Deficiency of vitamin A could lead to eye diseases such as bitot's spot, keratomalacia, night blindness and ultimately xerophthalmia (complete blindness), if not treated on time. Vitamin A deficiency could cause skin disorders like hyperkeratosis, phrynoderma. Vitamin A deficiency could even cause insufficient mucus production in the intestines and lung cells. It reduces the activity of immune system cells, leading to greater risk for infections. Also, in children, vitamin A deficiency could result in growth retardation and affect the gene expression.
On the contrary, excessiv...
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...Amsterdam: Elsevier. Retrieved from http://go.galegroup.com/ps/i.do?id=GALE%7CCX3032200286&v=2.1&u=hudsoncc&it=r&p=GVRL&sw=w&asid=2189a3fe71551f99a87077b8e5f6e95c
Ross, A. C. (2005). Physiology. In B. Caballero, L. Allen, & A. Prentice (Eds.), Encyclopedia of Human Nutrition (2nd ed., Vol. 4, pp. 329-339). Amsterdam: Elsevier. Retrieved from http://go.galegroup.com/ps/i.do?id=GALE%7CCX3032200339&v=2.1&u=hudsoncc&it=r&p=GVRL&sw=w&asid=7ce57440a352080698dd2fc52c0c63ab
Stanner, S. (2005). Safe Diet for Pregnancy. In B. Caballero, L. Allen, & A. Prentice (Eds.), Encyclopedia of Human Nutrition (2nd ed., Vol. 4, pp. [1]-8). Amsterdam: Elsevier. Retrieved from http://go.galegroup.com/ps/i.do?id=GALE%7CCX3032200285&v=2.1&u=hudsoncc&it=r&p=GVRL&sw=w&asid=35be4d487571cf904b491f0c3ff8a9a5
Wardlaw, G. (2013). Contemporary Nutrition. New York: Mc-graw Hill Companies Inc.
Marieb, E. N., & Hoehn, K. (2013). Human anatomy & physiology (9th ed.). Boston, MA: Pearson.
...heir diet during their pregnancy to treat all types of ailments. It is important to rule out any side effects, drug interactions or harm if any associated during pregnancy.
Phelan, J. (2011). What Is Life? A Guide To Biology with Physiology. New York: Peter Marshall.
Jared Diamond is a professor of geography at UCLA. He has a PhD in physiology and has spent his time since then researching molecular physiology and evolutio...
Marieb, E. N., (2006). Essentials of human anatomy and physiology. San Francisco, CA: Benjamin Cummings.
Mayo Clinic collaborative services educational publication. (2004). Mayo Clinic Guide to a Healthy Pregnancy. New York, NY, Harper Collins Publishers Inc.
Huether, S.E. & McCance, K.L. (2008). Understanding pathophysiology (4th ed.). St. Philadelphia, PA: Mosby Elsevier
The body can manufacture only vitamin D; all others must be derived from the diet. Lack of them causes a wide range of metabolic and other dysfunctions. In the U.S., since 1940, the Food and Nutrition Board of the National Research Council has published recommended dietary allowances (RDA) for vitamins, minerals, and other nutrients.
Crowley, L. (2010). Introduction to human disease: pathology and physiology correlations. Sudbury, MA: Jones & Bartlett
With over 600 carotenoids known to humankind, only 60 carotenoids are known to demonstrate vitamin A activity. When discussing AMD, the carotenoids of particular interest are known as xanthophylls – specifically lutein and zeaxanthin. Carotenoids are lipophilic and as a result they are absorbed via a similar mechanism to fat absorption. Similarly, carotenoids are integrated into chylomicrons and are transported throughout the body via the lipoprotein cycle. High-density lipoprotein is the primary transporter for xanthophylls, accounting for 53 percent of their transport to the retina.2, 6 Additionally, low-density lipoprotein and very-low-density lipoprotein account for 31 and 16 percent of xanthophyll transport respectively.2Lutein and zeaxanthin function as antioxidants; thus, they are capable of providing the Bruch’s membrane with a coping mechanism preventing ROS from damaging the RPE. Additionally, lutein and zeaxanthin are capable of filtering blue light and preventing excessive oxidative
My average intake is 66 mg. it is lower than the required Vitamin C intake. Deficiency in Vitamin C can develop scurvy, if vitamin C is missing on our diet. Oranges, lemon and other citrus fruits, bell pepper, kiwi broccoli, berries, tomatoes and papayas are rich in Vitamin C . Lack of Vitamin D on diet can develop rickets to small children. The required intake for this vitamins is 15microgram and my report is zero. Vitamin D can be achieved from exposure of skin to ultra violet rays of the sun. Vitamin E is responsible for transmission of nerve impulses, body weakness and eye problem that can cause blindness. My nutrient intake for Vitamin 10 mg AT and the require intake is 15 mg AT, which is 5 mg lower than the require amount. Food related to Vitamin E are green leafy vegies such as spinach, kale are rich in Vitamin E, in addition, broccoli, hazel nuts, squash and pumpkin are also rich in Vitamin E. My vitamin K intake is 3 microgram, way too low compared to the requirement which is 90 microgram. Vitamin K deficiency can cause hemorrhagic disease of new born. Food that gives Vitamin K are green leafy vegetables such as kale and spinach, canola oils, olive oils, and
Thibodeau, G & Patton, K. (2008) Structure and Function for the Body. 13th Edition. St. Louis: Mosby Elsevier.
When it comes to eating right, it is important that the diet of a pregnant woman has food energy, protein, with many vitamins and minerals, as this is essential for the pregnancy to support the metabolic demands of pregnancy and the baby's growth. It is then, that knowing the fact that the diet of a pregnant woman should be well controlled it is ide...
Hoehn, K. & Marieb, E. N. (2007). Human Anatomy & Physiology, Seventh Ed. San Francisco, CA: Pearson Education, Inc.
Illness is one of the main causes when you don’t have enough vitamins in your system because your immune is weak by not having any vitamin. A weak immune system can make you more susceptible to a common cold or fever. It seems that taking vitamin supplements does not work as well as taking vitamin in by a healthy diet. When eating unhealthy you could get different types of diseases. Having a high blood pressure can cause a higher risk of strokes and heart problems along with diabetes. Over time our population