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What is the function of hemoglobin in the blood?

One hemoglobin molecule in a mammal can carry up to four oxygen molecules. Hemoglobin also carries nitric oxide, an important regulatory molecule, and releases nitric oxide when it releases oxygen. Hemoglobin saturated with oxygen is called oxyhemoglobin, and hemoglobin without any oxygen is known as deoxyhemoglobin. Oxyhemoglobin is formed during physiological respiration when oxygen binds to the heme component of hemoglobin. This occurs in the pulmonary capillaries of the lungs.\nThe oxygen then travels through the blood stream to cells where it is used as a terminal electron acceptor in the..

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Why is the letter "K" used to represent a thousand?

The prefix "kilo" was taken from the Greek word chilioi or khilioi, which means thousand. This happened when a group of French scientists were commissioned to make the metric system. The metric system was designed to make conversions between units easier by making each unit a factor of 10 larger or smaller than the nearest units. Scientists needed to have standard prefixes that represented how much larger or smaller a specific unit was from the base unit. This makes it easy for a kilometer to be converted to a meter or a kilogram to a gram, because once the prefixes are known all conversions a..

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How are spring and summer wood different?

In temperate softwoods, spring wood is much lighter in color and weight than summer wood. These differences are apparent when the woods are compared by the naked eye but are more pronounced at the microscopic level. When examined by a microscope, cells of dense latewood are more compact than those in spring woods. Additionally, cells in summer wood have stronger and thicker walls and small cell cavities. Spring woods of temperate species, in contrast, have large cell cavities and thin cell walls. The thinner spring wood appears as a smaller ring and is generally softer and more flexible. This ..

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What is the difference between plant cells vs. animal cells?

Plant cells differ in structure from animal cells in that they have a cellulose wall that braces their plasma membranes. Animal cells lack this wall and therefore move with less difficulty than typical plant cells. Plant cells are eukaryotic, just as animal cells are, so both have a discrete nucleus. The nucleus of a plant cell, however, is usually localized in one spot near the wall of the cell, while an animal cell has a central nucleus that is not rigidly confined.\nPlant cells contain chloroplasts, organelles that animal cells lack, and have an internal chemical balance that favors the syn..

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How do astronauts drink in space?

Overcoming the dilemma of how to drink in space involves compensating for an environment in which there is no gravity. Liquids cannot be poured or sipped, or they float away. Drinks are sent into space as dehydrated powder, and astronauts add water through a special tube to liquefy them. The zero-gravity coffee cup uses a special principle involving a container with a sharp angle that allows the coffee to flow to the astronaut's mouth. In experiments with carbonated beverages, such as soft drinks and beer, astronauts found that the carbon dioxide bubbles, instead of floating to the top, r..

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What are the functions of the kidneys?

The kidneys work by filtering, reabsorbing and secreting substances, notes HowStuffWorks. They process 20 percent of the blood that comes from the heart. The blood comes in through the renal arteries, and the kidneys cleanse and then route it to the renal vein. Waste material collects in the urine, which leaves the kidneys through ureters that connect to the bladder. The urine and its waste material collect in the bladder for excretion later through the urethra.\nThe kidneys filter blood through a complicated process; basically, the blood travels from the renal artery into the arcuate arteries..

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What are the uses of pH in daily life?

Water is considered to have a neutral pH, which means it is neither acidic nor alkaline. The body can only handle certain pH levels, and anything above or below that level can be toxic. In cooking, pH is used to balance the flavors of food. Natural foods, such as vegetables, are often considered alkaline, while processed foods such as bread and cereal are acidic.\nThe body has its own preferred pH range that must be maintained through proper nutrition and lifestyle. Consuming too many acidic foods and beverages can cause heartburn and constipation over time. Having a low pH in the body can als..

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How is silver formed?

Silver is classified as a transition and precious metal. It is a transition metal because it is situated between groups two and 13 in the periodic table of elements. It is a precious metal because it is not very abundant in the Earth's crust and not very chemically active but very attractive. It is also a resistant mineral since it does not dissolve in solvents and does not react to oxygen or water. It often occurs as a free element in nature and can be extracted easily from ores. This is why it has been used by humans for thousands of years, specifically for photography, jewelry, electr..

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What are the main acupuncture points?

The meridians correspond to specific organ functions and ailments, explains Los Angeles Chinese Learning Center. The lung meridian is located inside the arm, just above the wrist, and it affects headaches, neck pain, pulmonary problems, facial paralysis and wrist pain. The stomach meridian is found below the front of the knee and affects issues related to nausea, vomiting, anemia, fatigue and immunity problems. The spleen meridian is above the inner ankle.\nThe gallbladder meridian is at the base of the skull and affects colds,headaches, neck pain, blood pressure and eye tension, states Los A..

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What are the parts of a gumamela flower?

More than 200 varieties of this plant are available, but all of them have some parts in common. Every variety of gumamela has a stamen and pistil, which are the male and female sex organs. The stamen contains a filament and two anthers that release pollen, and the pistil contains the ovary and other reproductive organs. At the top of the pistil sits the stigma, which is the site of pollen collection. The gumamela also has a calyx and a corolla. The calyx is the green structure that produces buds. The colorful part of the flower, which attracts insects, is the corolla.

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