Relationship Between Physics and Biology | Education - Seattle PI
Learn more about the similarities and differences of the branches of science The sciences that describe the physical universe are categorized in different ways. internal processes, and their relationship to each other and the environment. How other branches of science are taking help from Physics. Physics is the study of matter and the laws of nature to understand the The Biophysical Society explains that, when scientists combine physics and biology, they of Biology; 2 Types of Microbiology; 3 What Are the Branches of Physiology? Volume I, The Relationship of Physics to Other Sciences · Cornell University.
Physics can be divided into experimental and theoretical physics. Historically, theoretical physics has correctly predicted phenomena that were out of experimental reach at the time, and could be verified only after experimental techniques caught up.
Training[ edit ] In a typical undergraduate program for physics majors, required courses are in the sub-disciplines of physics, with additional required courses in mathematics. Because much of the insight of physics is described by differential equations relating matter, space, and time for example Newton's law of motion and the Maxwell equations of electromagnetismstudents have to be familiar with differential equations.
In a typical undergraduate program for chemistry majors, emphasis is placed on laboratory classes and understanding and applying models describing chemical bonds and molecular structure.
Emphasis is also placed in the methods for analysis and the formulas and equations used when considering the chemical transformation. Students take courses in math, physics, chemistry, and often biochemistry. Between the two programs of study, there is a large area of overlap calculusintroductory physics, quantum mechanicsthermodynamics. These very large and complicated things are called enzymes.
They were first called ferments, because they were originally discovered in the fermentation of sugar. In fact, some of the first reactions in the cycle were discovered there.
Relationships Between Physical & Life Sciences
In the presence of an enzyme the reaction will go. An enzyme is made of another substance called protein. Enzymes are very big and complicated, and each one is different, each being built to control a certain special reaction. The names of the enzymes are written in Fig. Sometimes the same enzyme may control two reactions. We emphasize that the enzymes themselves are not involved in the reaction directly. They do not change; they merely let an atom go from one place to another.
Having done so, the enzyme is ready to do it to the next molecule, like a machine in a factory. Of course, there must be a supply of certain atoms and a way of disposing of other atoms.
Take hydrogen, for example: For example, there are three or four hydrogen-reducing enzymes which are used all over our cycle in different places. It is interesting that the machinery which liberates some hydrogen at one place will take that hydrogen and use it somewhere else.
The most important feature of the cycle of Fig. So, GTP has more energy than GDP and if the cycle is going one way, we are producing molecules which have extra energy and which can go drive some other cycle which requires energy, for example the contraction of muscle. The muscle will not contract unless there is GTP.
An enzyme, you see, does not care in which direction the reaction goes, for if it did it would violate one of the laws of physics. Physics is of great importance in biology and other sciences for still another reason, that has to do with experimental techniques. In fact, if it were not for the great development of experimental physics, these biochemistry charts would not be known today. The reason is that the most useful tool of all for analyzing this fantastically complex system is to label the atoms which are used in the reactions.
They are different isotopes. We recall that the chemical properties of atoms are determined by the number of electrons, not by the mass of the nucleus. But there can be, for example in carbon, six neutrons or seven neutrons, together with the six protons which all carbon nuclei have.
Now, we return to the description of enzymes and proteins. Not all proteins are enzymes, but all enzymes are proteins. There are many proteins, such as the proteins in muscle, the structural proteins which are, for example, in cartilage and hair, skin, etc. However, proteins are a very characteristic substance of life: Proteins have a very interesting and simple structure.
They are a series, or chain, of different amino acids. There are twenty different amino acids, and they all can combine with each other to form chains in which the backbone is CO-NH, etc.
Proteins are nothing but chains of various ones of these twenty amino acids. Each of the amino acids probably serves some special purpose. Some, for example, have a sulfur atom at a certain place; when two sulfur atoms are in the same protein, they form a bond, that is, they tie the chain together at two points and form a loop. Another has extra oxygen atoms which make it an acidic substance, another has a basic characteristic. Some of them have big groups hanging out to one side, so that they take up a lot of space.
One of the amino acids, called proline, is not really an amino acid, but imino acid. There is a slight difference, with the result that when proline is in the chain, there is a kink in the chain. If we wished to manufacture a particular protein, we would give these instructions: In this way, we will get a complicated-looking chain, hooked together and having some complex structure; this is presumably just the manner in which all the various enzymes are made.
One of the great triumphs in recent times sincewas at last to discover the exact spatial atomic arrangement of certain proteins, which involve some fifty-six or sixty amino acids in a row. Over a thousand atoms more nearly two thousand, if we count the hydrogen atoms have been located in a complex pattern in two proteins. The first was hemoglobin.
One of the sad aspects of this discovery is that we cannot see anything from the pattern; we do not understand why it works the way it does. Of course, that is the next problem to be attacked. Another problem is how do the enzymes know what to be? A red-eyed fly makes a red-eyed fly baby, and so the information for the whole pattern of enzymes to make red pigment must be passed from one fly to the next.
This is done by a substance in the nucleus of the cell, not a protein, called DNA short for desoxyribose nucleic acid. This is the key substance which is passed from one cell to another for instance sperm cells consist mostly of DNA and carries the information as to how to make the enzymes.
Relationship Between Physics and Biology
First, the blueprint must be able to reproduce itself. Secondly, it must be able to instruct the protein. Concerning the reproduction, we might think that this proceeds like cell reproduction. Cells simply grow bigger and then divide in half.
Must it be thus with DNA molecules, then, that they too grow bigger and divide in half? Every atom certainly does not grow bigger and divide in half! No, it is impossible to reproduce a molecule except by some more clever way. Schematic diagram of DNA. The structure of the substance DNA was studied for a long time, first chemically to find the composition, and then with x-rays to find the pattern in space. The result was the following remarkable discovery: The DNA molecule is a pair of chains, twisted upon each other.
The backbone of each of these chains, which are analogous to the chains of proteins but chemically quite different, is a series of sugar and phosphate groups, as shown in Fig. Thus perhaps, in some way, the specific instructions for the manufacture of proteins are contained in the specific series of the DNA.
Attached to each sugar along the line, and linking the two chains together, are certain pairs of cross-links. Whatever the letters may be in one chain, each one must have its specific complementary letter on the other chain. What then about reproduction? Suppose we split this chain in two. How can we make another one just like it? This is the central unsolved problem in biology today.
The first clues, or pieces of information, however, are these: There are in the cell tiny particles called ribosomes, and it is now known that that is the place where proteins are made. But the ribosomes are not in the nucleus, where the DNA and its instructions are. Something seems to be the matter. However, it is also known that little molecule pieces come off the DNA—not as long as the big DNA molecule that carries all the information itself, but like a small section of it.
This is called RNA, but that is not essential. It is a kind of copy of the DNA, a short copy. The RNA, which somehow carries a message as to what kind of protein to make goes over to the ribosome; that is known. When it gets there, protein is synthesized at the ribosome. That is also known. However, the details of how the amino acids come in and are arranged in accordance with a code that is on the RNA are, as yet, still unknown.
We do not know how to read it. Certainly no subject or field is making more progress on so many fronts at the present moment, than biology, and if we were to name the most powerful assumption of all, which leads one on and on in an attempt to understand life, it is that all things are made of atoms, and that everything that living things do can be understood in terms of the jigglings and wigglings of atoms.
Astronomy is older than physics. In fact, it got physics started by showing the beautiful simplicity of the motion of the stars and planets, the understanding of which was the beginning of physics. But the most remarkable discovery in all of astronomy is that the stars are made of atoms of the same kind as those on the earth.
Physics - Wikipedia
Atoms liberate light which has definite frequencies, something like the timbre of a musical instrument, which has definite pitches or frequencies of sound. When we are listening to several different tones we can tell them apart, but when we look with our eyes at a mixture of colors we cannot tell the parts from which it was made, because the eye is nowhere near as discerning as the ear in this connection.
However, with a spectroscope we can analyze the frequencies of the light waves and in this way we can see the very tunes of the atoms that are in the different stars. As a matter of fact, two of the chemical elements were discovered on a star before they were discovered on the earth. Helium was discovered on the sun, whence its name, and technetium was discovered in certain cool stars.
This, of course, permits us to make headway in understanding the stars, because they are made of the same kinds of atoms which are on the earth. Now we know a great deal about the atoms, especially concerning their behavior under conditions of high temperature but not very great density, so that we can analyze by statistical mechanics the behavior of the stellar substance.
Even though we cannot reproduce the conditions on the earth, using the basic physical laws we often can tell precisely, or very closely, what will happen.
Weak does not, however, mean non-existent. There are real cases where biologists and physicists can find ways to work together. The field is called biophysics. Biophysics is a field of study where physics theories and methods are used to study biological systems.
Biophysics generally tries to explain a lot of the same phenomena as biochemistry and molecular biology, but tries to do so numerically, creating equations that can describe what is being observed. Physics technology can also be used in this field to explain some of these observations, including spectroscopy, x-ray crystallography, scattering effects, and the use of electron microscopes. All of these technologies are mainstays of physics research, but are less used in life sciences.