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What is a non-polar molecule?

A non-polar molecule is hydrophobic and will only dissolve in lipids, making it lipophilic. The bonds holding its atoms together are generally covalent, since a non-polar molecule does not form hydrogen bonds. The attractive forces exerted between non-polar molecules are weak intermolecular forces known as the "London dispersion forces." These forces become relatively stronger a higher number of electrons come in contact with each other. Carbon compounds, such as carbon dioxide and methane, are some of the most common non-polar molecules.

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What is the definition of instantaneous speed?

Because instantaneous speed is a real time number, it can change frequently throughout its journey. If an object slows down, every second that it's slowing is a change in the instantaneous speed. Likewise, if it speeds up, every second that it's accelerating changes the instantaneous speed. However, average speed is a calculation of the speed an object was traveling at any given moment within a journey based on the total distance traveled and the total amount of time required to get to a destination. This is also referred to as the distance per time ratio. Speed has a proportional re..

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What are ultimate and proximate causes?

Since ultimate causation cannot be measured but proximate causation can, it is said to be unquantifiable. Ultimate factors are sometimes called root causes because they are realized only when examining deeper layers of proximate factors. Proximate factors are grouped together to form a set of proximate causes that represent a hypothesis. Yet, proximate and ultimate causes deal with questions of how and why and both have applications in other fields. Wikipedia notes that in biology, ultimate causation deals with evolutionary forces that affect traits, and proximate causation deals with biologic..

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What are the advantages and disadvantages of cross pollination?

Cross pollination is one way in which plants reproduce. There are many advantages to this method, the foremost is introducing genetic diversity to the plant, which keeps is resistant to disease. According to How Stuff Works, cross pollination is necessary to produce hybrid plants and flowers, which keeps the species strong.\nOf course, there are also many disadvantages to cross pollination. For one, Diffen points out that it prevents uniform progeny and the purity of the genetic pool. It is also hard to guarantee cross pollination. In some cases this means that there is too much distance betwe..

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What is the function of the immune system?

The immune system is comprised of many different cells. One of the main immune cells in the human body is the white blood cell, or leukocyte. There are two basic forms of white blood cells. These include the phagocytes, which digest and destroy invading pathogens, and the lymphocytes, which tag and recognize invading pathogens. The lymphocytes also help the human body produce memory cells that quickly recognize and destroy pathogens that the body has previously encountered. The immune system is working at all times to destroy pathogens and keep the human body healthy.

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What are red bumps in the whites of the eyes?

Bedinghaus states on About.com that the red spots are easily noticeable because of the white background of the eye, and they can cause alarm if they appear unexpectedly. Consult an eye doctor if a new red spot appears. The treatment depends on the underlying factor. Red spots are most likely caused by subconjunctival hemorrhage, which is bursting of a blood vessel.

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What are examples of protozoa?

Medical Microbiology explains that more than 50,000 species of protozoa have been classified. The first protozoa to be described was discovered by Anton van Leeuwenhoek between 1674 and 1716 when he observed the parasite Giardia lamblia in his own stool. At some point during the life cycle of a human being, it is almost certain that one or more of the many species of parasitic protozoa make their home in the human body. The consequences of such an infection range from entirely asymptomatic to potentially life threatening. Some diseases caused by protozoa infections include malaria, trypanosomi..

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What is the electromagnetic theory?

There are four phenomena involved in this theory. The first states that the force of attraction or repulsion between electric charges is inversely proportional to the square of the distance between them. The second states phenomena involves magnetic poles, stating that magnetic poles come in pairs and that either attract or repel each other as much a electric charges do. The third states that the direction of the magnetic field produced by the electric current in the wire is dependent on the direction of the current. And lastly, the fourth theory states that a moving electric field produces a ..

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What substances act as natural buffers?

The three carbon molecules are collectively referred to as the "carbonate system." This system can decrease the pH of the water when necessary by donating a proton from bicarbonate to form carbonate. If the water then becomes too acidic, both carbonate and bicarbonate are capable of accepting a proton, thereby lowering the concentration of hydrogen ions and raising the pH.\nSince each of these molecule types are present in a dynamic equilibrium, any small change in the concentration of one molecule will have an effect on the concentration of all the others. This phenomenon is described by LeCh..

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What is the liquid portion of the blood called?

The University of Rochester Medical Center states that blood is made mostly of plasma. Along with the blood cells, plasma transports vital nutrients, proteins and hormones to the body's cells, and in return, the cells deposit their waste into the plasma so that it can be removed from the body. To obtain plasma in its pure form, a process called plasmapheresis is performed after a blood donation, which separates the plasma from the blood cells and platelets.

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