Red Blood Cells

Red Blood Cells

 Red Blood cells, the most abundant blood cell, is located through 40-45% of the body. Shaped like a disk with a flattened center, 5 million of these 6-8 micrometer diameter cells are present in every cubic millimeter of blood.  Originally, red blood cells begin as immature cells located in the bone marrow and is later released into the blood after approximately a week with the help of erythropoietin, a hormone produced from the kidneys. These connective tissues play a vital part in the human body, such as regulating metabolism, getting rid of harmful bacteria, and transferring oxygen from the lungs to tissues.

 While red blood cells have lipids and proteins, red blood cells are missing a nucleus.   Unlike most cells, red blood cells don't need to divide to replicate, there is no need of a nucleus. Without a nucleus, red blood cells can also carry more oxygen and fit into smaller blood vessels due to its flexibility. Unfortunately, this limits the life of the cell since the cell's membranes become damaged more quickly. On average, red blood cells can survive about 120 days, or 4 months.




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Sweetness Lab Reflection

  Today, in Anatomy and Physiology, we completed the Sweetness Lab, where we sampled 8 types of carbohydrates. We determined the type of carbohydrate, the degree of sweetness, the color, the texture, and the functions of each one. After sampling the various types of carbohydrates, we concluded that the carbohydrates with fewer rings were sweeter, making monosaccharides sweeter than disaccharides and polysaccharides. For instance, we rated starch and cellulose, both polysacharides, a "0" in terms of sweetness. Both of these carbohydrates resembled the bland taste of paper due to the fact that both carbohydrates were derived from trees. On the contrary, both fructose and sucrose, both disaccharides, were much sweeter. Both of these disaccharides are found in numerous sweeteners such as high fructose corn syrup and honey.

  In the NPR article, Getting a Sense of How We Taste Sweetness, Dr. Robert Margolskee explains how one can taste something sweet. Margolskee claims that when the sweet receptor protein and the sweetener encounter each other, the sweet taste sends a signal to the brain, which causes certain parts of the central nervous system to respond to sweet. Margolskee believes that it closely resembles a "lock and key" since "when they (sugar and sweet receptor protein) encounter each other, it opens a lock. The door opens up."



(Photo of the carbohydrates we sampled)