More and more, credible scientists, those who are looking for truth and not pursuing an agenda, are coming to terms with the understanding that so much of what they observe from the cell to the universe is fitted together so precisely that it could only be done by a all powerful Creator and Designer, what we Christians would call God.
More and more science is seeing “intelligent Design” as unavoidable. Just the intricate design of the cell, of which the human body consists of millions, could simply not have happened by accident.
The problem is, that the fundamentalists, the biased priests of the faith of “Evolution”, “Darwinism”, live in a state of constant denial. Don’t try to confuse me with the facts of actual science, my faith dictates that there is no God. Part of that is the result of being hurt, suffering trauma and striking back at God. Another reason is that they have a particular life style, and like a 15 year old adolescent, tenaciously clinging to their sin instead of submitting to a loving, forgiving Father, they simply deny God and try to sell everyone that they should live however they want in order to “be happy”, “be fulfilled”. You know “don’t judge me” whine. Well we’ve certainly seen the results in society, slavery to sin of substance abuse, sexual addiction, worshipping money, things, lifestyles and just refusing to realize the destructive results.
I could certainly go on, I doubt anyone out there would argue with me on that, but I thought I would straight reblog from an actual scientist. Dr Howard Glicksman MD is a Medical Doctor in private practice in Florida. I have taken his blogs off the Discovery Institute in which he writes about the cell. I have also included the link to the “Discovery Institute” which consists of writings from objective scientists on many issues.
http://www.evolutionnews.org/intelligent_design/
How the Body Works: Intelligent Design in Action
Howard Glicksman February 26, 2015 5:00 AM | Permalink
Editor’s note: Engineers and physicians have a special place in the community of thinkers and scholars who have elaborated the argument for intelligent design. Perhaps that’s because, more than evolutionary biologists, they are familiar in very practical ways with the challenges of designing or maintaining a functioning complex system on the order of a jet airplane, or the human body. With that in mind, Evolution News & Views is delighted to introduce a new series, “The Designed Body,” and to welcome Howard Glicksman MD as a contributor. A graduate of the University of Toronto (1978), he presently practices palliative medicine for a hospice organization. Here, Dr. Glicksman explains the rationale behind the series.
Have you ever wondered why it’s so hard to hold your breath, or how your body automatically matches your breathing with your level of activity? Whether you’re running to catch a bus, talking to friends, or just sleeping on the sofa, your body seems to know just how fast and hard you should breathe.
Or have you wondered why even if you go hours or days without eating, your body automatically makes sure it has enough glucose in your blood so you can keep doing what you want to do?
To understand such things you must first know how the laws of nature affect the body and how it must work against them to stay alive.
Everything in the world is made up of matter. All matter consists of many different types of atoms chemically bonded to form different types of molecules. All matter mustfollow the rules of physics and chemistry. Just like our planet where two-thirds is covered by water and one-third by land, our body is roughly two-thirds water and one-third other matter. But, unlike most of the earth, our “water and dust” is organized for life. The body is made up of trillions of cells each of which contains trillions and trillions of atoms and molecules. Since our cells are made up of atoms and molecules, this means that they too must obey the laws of nature.
We each experience these natural forces every day: inertia, friction, momentum, gravity, and heat transfer, to name a few. Experience teaches that, due to the laws of nature, our body has definite physical and chemical limitations. Jump down from a high ledge and you’re likely to break your leg because of the force of gravity and the fact that your leg is made of bone, not rubber. Put your hand into a fire and you’re likely to burn your fingers due to the transfer of heat energy and the fact that your body is mostly made of flesh, not asbestos. Breathing in enough air to match your level of activity, and making sure there’s enough glucose in your blood to provide enough energy to all of your cells, are just two of the ways your body must follow the rules to win in the game of life.
But, like in any game, to follow the rules means that you must first take control. If you’re playing baseball you can’t hit the ball just anywhere or run the bases any which way. By taking control you must try to keep the ball in fair territory and run the bases correctly. So too, your body must be able to take control of many different chemicals and functions.
However, whether the context is baseball or the battle for survival, experience tells us that just following the rules and taking control don’t automatically mean that you’ll win. At the end of the baseball game, if your opponent has scored more runs than you have, then you’ve lost. So too, if the body doesn’t have just the right level of oxygen, or glucose, or water, or salt, or calcium, or red blood cells, or white blood cells, or blood pressure, or temperature, then it can’t stand up to the laws of nature. It loses the game of life, and dies. In other words, real numbers have real consequences.
Death is an inevitable consequence of life and the mechanisms that result in its taking place should be fully understood and incorporated into any theory of how life came about.
If you really want to understand how life came into existence you must first understand how easily it can become non-existent. Just as a mechanic knows that there are many different ways a car can “die,” so too every physician knows that there are many different pathways to death. Theories about life that only describe where the different parts may have come from, or even how they may have come together to perform a specific function, as difficult as that may be, are not good enough. For medical science knows that when the body has allowed the rules of physics and chemistry to take over, having lost control and not being able to maintain the right level of any one chemical or vital function, then the consequence is death.
Some people believe that life came into being by chance and the laws of nature alone. Darwin was an excellent observer of nature but he had no idea how life actually works at the cellular or molecular levels. All clinical experience teaches that trying to explain how human life came into being just by looking at ancient bones, without considering their complicated cellular structure and physiology along with their vital importance in heart, nerve, gland, muscle, and clotting function, is like trying to explain how airplanes came into being just by looking at the fuselage, the wings, the tail section, and the engines without considering, among other things, modern metallurgy, jet propulsion, aerodynamics, and electronics.
In this series, I plan to show how the body works and how the only plausible explanation for its ability to combat the laws of nature and survive in the world are the many physiological innovations that must have come about through intelligent design.
Contrary to what evolutionary biologists would have us believe, medical experience shows that when left to their own devices, chance and the laws of nature cause disability and death, not functional ability and life. Looking at one important chemical and physiological parameter of body function at a time, I propose to explain its vital significance and how the body goes about controlling it to stay alive.
Finally, using clinical experience, I will discuss what happens when things go wrong and organ malfunction takes place.
It is my hope that what I have to say will empower you to defend yourself from what I think is the greatest intellectual and spiritual error in human history: the idea that human life has come about by chance and the laws of nature alone.
Image by yftahp (אני יצרתי) [CC BY-SA 3.0], via Wikimedia Commons.
Each Cell in Your Body Is a Walled City Besieged by Enemies
Howard Glicksman March 2, 2015 3:53 AM | Permalink
Editor’s note: Engineers and physicians have a special place in the community of thinkers and scholars who have elaborated the argument for intelligent design. Perhaps that’s because, more than evolutionary biologists, they are familiar in very practical ways with the challenges of designing or maintaining a functioning complex system on the order of a jet airplane, or the human body. With that in mind, Evolution News & Views is delighted to present this new series, “The Designed Body,” and to welcome Howard Glicksman MD as a contributor. A graduate of the University of Toronto (1978), he presently practices palliative medicine for a hospice organization. Find Dr. Glicksman’s introduction to the series here.
Just as a brick is the basic building block of a wall, the human cell is the basic functioning unit of the human body. Our body has about a hundred trillion of them. And just as with a brick wall, the requirement that it not collapse means being sturdy enough to stand up to the forces of nature, our cells likewise need to stand up to nature. For this reason, and others, the two hundred different types of cells in the body have common features that allow them to follow the rules to live, grow, and work properly.
In Darwin’s day, a cell was considered to be just a bag of chemicals containing within it various structures of unknown function. During the last century it has been shown that the cell is a huge software-driven micro-sized city containing many different nano-sized buildings with programmed pico-sized machines that are able to use energy to build the structures and perform the functions necessary for life. Here is a brief summary of some of the aspects of the human cell which must first be understood to appreciate why it must take control to survive in the world.
A very thin wall, called the plasma membrane, surrounds the cell. The plasma membrane defines the limits of the cell and separates it from other cells and from the outside world. It serves to keep what is needed inside the cell and what is not needed outside the cell. The important chemicals and vital structures of the cell would not be very useful if they were not kept in one place.
The main substance of the cell, which fills up the space within the plasma membrane, is a fluid called the cytosol. The cytosol consists of water with different chemicals dissolved within it. The amount of water inside the cell is its volume and the total number of chemical particles dissolved within each unit volume of water is its concentration. The cytosol is said to be more concentrated when there are more chemical particles per unit volume of water and less concentrated when there are fewer chemical particles per unit volume of water. Also, for a given number of chemical particles in the cytosol, an increase in volume results in a decrease in concentration and a decrease in volume results in an increase in concentration.
Each cell not only consists of water, but is also surrounded by water. The water inside the cell has a high concentration of potassium and protein and a low concentration of sodium. The water outside the cell has a high concentration of sodium and a low concentration of potassium and protein. In other words, the chemical make-up of the water inside the cell is exactly the opposite of the water outside. The plasma membrane serves to separate the two different solutions from each other.
Since the water in the cell takes up space, it applies a certain amount of pressure against the plasma membrane. Think of a bicycle tire. The more it is pumped up, the more air pressure is applied against the tire wall. Since the plasma membrane is made up of matter with a specific structure, like the bicycle tire, it too has physical limits when it comes to remaining intact and functional under pressure.
Suspended within the cell are structures, called organelles, and important proteins which together perform functions that allow for life. These include the nucleus, which contains the genetic information the cell needs to live and reproduce, the mitochondria, where the energy for cell function is obtained, the rough endoplasmic reticulum and the golgi apparatus, which are the factories that produce proteins, the lysosomes, which are the recycling plants where used cellular material is broken down, and the microtubules and microfilaments, which are the supportive cytoskeleton that allows the cell to alter its shape in response to changes in its environment.
Now consider what some of the laws of nature demand for the cell to survive in the world. Real numbers have real consequences. If the cell can’t take control to follow the rules, then life will quickly turn into death.
Whether it’s a mountain, a molehill, or a molecule, all material objects have mass and so energy is needed to change them. Therefore, to produce, move, or control anything requires that the cell have enough energy. Like a light bulb short on electricity or a car short on gas, without enough energy the cell is as good as dead.
The chemical content in the cell must be kept relatively constant for it to live and work properly. This means that the fluid inside the cell must maintain its high level of potassium and protein and its low level of sodium. If the chemical content of the cell isn’t in the right range, then the cell dies a quick death.
Finally, as noted above, the plasma membrane surrounding the cell has definite physical limitations and is therefore sensitive to changes in pressure. Think of blowing up a balloon. There is only so much air pressure the wall of the balloon can handle before it explodes. So too the volume of the cell must be kept within certain limits. If the water pressure against the plasma membrane rises too high, then, as with a balloon, cell death will take place, literally by explosion.
Note, too, that the cell is not self-sufficient. To survive it needs to constantly receive new supplies of chemicals, like glucose, for energy. It must also constantly rid itself of toxic chemicals, like carbon dioxide from the breakdown of glucose. However, to survive, the cell faces a major dilemma. In letting these chemicals pass through its plasma membrane, the cell is exposed to the chemical content of the water just outside its doorstep. And remember, the chemical content of the water outside is totally different from that of the water inside the cell. The cell, remember, must control its chemical content and volume to stay alive.
Think of a walled city besieged by enemies. The residents of the city are slowly running out of food and water and are in desperate need of new supplies to stay alive. They must somehow be able to open the gates wide enough to bring in what they need without at the same time being overrun by the enemy.
In allowing these chemicals to pass through its plasma membrane the cell comes up against a dilemma, a result of the laws of nature that govern chemical and fluid movement. In letting down its guard to allow some chemicals to come in and go out, the cell runs the risk of losing control of its chemical content and volume. If that happens, the cell will perish.
Which laws of nature are involved in the cell’s dilemma and, if not resisted by some ingenious design, how do they bring about the catastrophe that is cell death? Come back next time and we’ll find out.
Image: Turkish Siege of Vienna, Vienna Museum, Tyssil (own work) [CC BY-SA 3.0], via Wikimedia Commons.
Diffusion and Osmosis: Twin Perils in the Life of the Cell
Howard Glicksman March 6, 2015 3:19 AM | Permalink
Editor’s note: Engineers and physicians have a special place in the community of thinkers and scholars who have elaborated the argument for intelligent design. Perhaps that’s because, more than evolutionary biologists, they are familiar in very practical ways with the challenges of designing or maintaining a functioning complex system on the order of a jet airplane, or the human body. With that in mind, Evolution News & Views is delighted to present this new series, “The Designed Body,” and to welcome Howard Glicksman MD as a contributor. A graduate of the University of Toronto (1978), he presently practices palliative medicine for a hospice organization. Find Dr. Glicksman’s introduction to the series here.
Earlier we looked at what the human cell consists of and what it requires to live. Our cells need energy to perform their vital functions, including the ability to control their chemical content and volume. The cell faces a dilemma: it must let certain chemicals pass through its plasma membrane, while at the same time ridding itself of what is harmful. This dynamic exposes the cell to the laws of nature which if not resisted could drastically alter its chemical content and total volume, resulting in death. We turn now to the two main natural forces, diffusion and osmosis, that constantly threaten cell life.
Diffusion refers to the natural law that chemical particles in solution always remain in motion and spread out evenly in their medium. Therefore, when a solute (like salt) is dissolved in a solvent (like water) it forms a mixture that is homogeneous. This means that the salt particles in solution are equidistant from each other, and the chemical make-up of the salt water is the same everywhere. The salt water at the top of the container is chemically identical to the salt water in the middle and the salt water in the middle of the container is identical to the salt water at the bottom.
Moreover, when two solutions with different concentrations of salt are separated by a membrane that is permeable, meaning that it allows both the salt (solute) and the water (solvent) to pass through, diffusion naturally makes the salt from the solution with a higher concentration move into the one with a lower concentration.
This movement, called “diffusing down its concentration gradient,” is like moving down the slope of a hill, from a higher to a lower elevation. Except in this case, the movement of salt from the solution with a higher concentration to a lower concentration is taking place by the power of diffusion rather than the force of gravity. The final result of this movement of salt between the two solutions is they end up having the same concentration, the actual numerical value being somewhere between the original two.
The biological significance to the cell is that the fluid inside of it has a high concentration of potassium and a low concentration of sodium while the fluid outside has a low concentration of potassium and a high concentration of sodium. The plasma membrane of the cell that separates these two fluids is permeable to potassium, sodium, and water. So, if left unchecked, by following the rules, the power of diffusion would make potassium move down its concentration gradient, from the fluid inside the cell to the outside, and sodium move down its concentration gradient, from the fluid outside the cell to the inside.
If there were no mechanism in place to resist this natural movement, by diffusion, of potassium out of the cell and sodium into the cell, then life as we know it would not exist. As noted already, one of the main things the cell has to do to survive is take control and maintain its chemical content. However, diffusion is not the only natural force the cell has to contend with to stay alive. The other one, which affects the cell’s ability to control its volume, is osmosis.
Osmosis takes place when two solutions of different concentration are separated by a semi-permeable membrane in which the solvent can pass through but not the solute. For salt water this would mean that the salt cannot pass through the membrane but water can. Osmosis would naturally make water move from the solution with less concentration of salt to the one with more. This is exactly the opposite of what happens in the diffusion of chemicals, like sodium and potassium, across a permeable membrane.
Since the salt cannot pass through the membrane, but water can, the water moves across in the opposite direction instead so the concentration on both sides will be the same, somewhere between the original two. However, since the semi-permeable membrane only lets water pass through, a change in volume also takes place on both sides. Due to the power of osmosis, the volume of the solution that had a higher concentration of salt, rises, while the volume of the solution that had a lower concentration of salt, falls.
The biological significance of osmosis to the cell is that the fluid inside the cell has a much higher concentration of protein than the fluid outside the cell. Although the plasma membrane is permeable to solutions of sodium and potassium, it is only semi-permeable to ones with protein, i.e., it lets water pass through but not protein. This takes place because sodium and potassium are very small ions that can slip through most biological membranes, but most proteins are very large molecules that can’t. This is important for survival. The cell makes many different proteins that perform vital functions, and if they were able to easily pass through the plasma membrane and leave the cell by diffusion, then the cell wouldn’t be able to work properly and would die.
However, the fact that protein can’t cross the membrane, but water can, makes the cell susceptible to the power of osmosis. As the potassium and sodium ions naturally move, by diffusion, in opposite directions across the plasma membrane, the much higher protein content inside the cell (which can’t leave it) follows the rules and makes water enter the cell by osmosis. If too much water enters the cell, causing its volume to rise and too much pressure to be applied against the plasma membrane, the cell can die by explosion, just like a balloon. As we once again see, one of the main things the cell needs to do to survive is take control and maintain its volume.
Cell death under these circumstances verifies that real numbers have real consequences. When the cell follows the rules, like diffusion and osmosis, it runs the risk of losing control and dying. So by what innovative mechanism do our cells combat the natural forces of diffusion and osmosis? That question must wait till next week.
Image by Adam Jones Adam63 (Own work) [CC BY-SA 3.0], via Wikimedia Commons.
Pumping for Life: What the Sodium-Potassium Pump Accomplishes
Howard Glicksman March 10, 2015 3:04 AM | Permalink
Editor’s note: Engineers and physicians have a special place among the thinkers and scholars who have elaborated the argument for intelligent design. Perhaps that’s because, more than evolutionary biologists, they are familiar in very practical ways with the challenges of designing or maintaining a functioning complex system on the order of a jet airplane, or the human body. With that in mind, Evolution News & Views is delighted to present this series, “The Designed Body.” Dr. Howard Glicksman practices palliative medicine for a hospice organization.
In this series we’ve seen what makes up the human cell and what it needs to do to survive, given the laws of nature. One of the main things the cell must do is control its chemical content and volume. If not combated by some sort of innovation, the natural forces of diffusion and osmosis have the potential to quickly bring about cell death. This is due to the fact that the chemical make-up of the fluid inside the cell is exactly the opposite of the fluid outside the cell, and the cell must let the chemicals it needs to live (like glucose) come in and the toxic ones it produces (like carbon dioxide) go out through the plasma membrane. In having a plasma membrane that is permeable to certain chemicals, but not to others (like most proteins), the cell must follow the rules — entailing that it is affected by the natural forces of diffusion and osmosis.
Diffusion has the potential to drastically alter the cell’s chemical content by naturally causing potassium leave the cell through its plasma membrane while causing sodium to enter. And while diffusion is trying to make potassium and sodium equalize within the fluid inside and outside the cell, osmosis has the potential to drastically alter the cell’s volume by naturally making water enter the cell at the same time because its large amount of protein can’t cross the plasma membrane. Together, the effects of diffusion and osmosis can give the cell a one-two punch, quickly resulting in death. What kind of mechanism could possibly do the job of controlling not only the cell’s chemical content but its volume too?
Consider what you would have to do if you were sitting in a boat that constantly had water leaking into it. Of course, you would have to constantly remove that water, otherwise the boat will sink. But, what if your only option is to keep the boat in the water and you can’t be there to do the work of bailing all the time? Could you place a machine in the boat to do the work for you? That is, a pump. This is precisely the type of micro-machine the cell uses to take control of its chemical content and volume. In fact, the cell has a few million of these sodium-potassium pumps within its plasma membrane.
The sodium-potassium pump acts by pushing sodium out of the cell and pulling potassium back in. Even though the laws of nature make sodium go into, and potassium go out of, the cell as they diffuse down their respective concentration gradients, the millions of sodium-potassium pumps in the plasma membrane immediately reverse most of this movement. In fact for every three ions of sodium that are pumped out of the cell, two ions of potassium are pumped back in.
This is how the cell reverses the natural tendency for the fluid inside and outside to have equal concentrations of sodium and potassium. In so doing, it maintains its chemical content. However, the action of the sodium-potassium pump not only preserves the cell’s chemical content, it also controls its volume by preventing water from entering as. Here is how.
Remember, as chemicals like sodium and potassium move across the permeable plasma membrane and diffuse down their concentration gradient, water rushes into the cell due to the large amount of impermeable protein pulling it in by osmosis. In other words, in biology, a solute exerts an osmotic pull on water across a membrane based on its inability to leave that solution. Again, since protein can’t leave the fluid in the cell, because it can’t go through the plasma membrane, it’s able to apply an osmotic pull on the water outside the cell and bring it inside. Since sodium and potassium freely pass across the plasma membrane, they should not be able to apply an osmotic pull on water in either direction. Or can they?
With the sodium-potassium pumps in the plasma membrane of the cell pushing most of the sodium back out of the cell and bringing most of the potassium back in, although they are still permeable, they now effectively act as if they were impermeable. By forcing sodium and potassium to stay where they are, the sodium-potassium pumps give them the power to move water toward them by osmosis. As noted above, in biology, a solute exerts an osmotic pull on water across a membrane based on its inability to leave that solution. With the sodium-potassium pumps forcing sodium to stay outside the cell and keeping potassium inside, they have effectively made them unable to leave their solution. In doing so, the sodium-potassium pumps have also made sodium and potassium osmotically active chemicals, just like the protein inside the cell.
This means that, not only does protein have a tendency to pull water into the cell from the fluid outside, but so does potassium as well. In addition, since the sodium-potassium pumps push sodium out of the cell, not letting it stay on the other side of the plasma membrane, it also enables sodium to pull water from inside the cell back outside. The osmotic pull of sodium from outside the cell is in the opposite direction to the osmotic pull exerted by the protein and potassium inside it. In fact, the cell is very sensitive to water movement in either direction across its plasma membrane, which directly affects its volume. To take control of its volume the cell always tries to make sure that the osmotic pull of water from the fluid outside the cell evenly matches the pull to bring water back in. It does this by making certain that the concentration of total chemical particles in the cytosol is the same as in the fluid outside the cell. When this is achieved, the fluids are said to be isotonic.
This is what the sodium-potassium pump accomplishes. But there is a price to be paid by the body for thus battling the forces of nature. The job of the sodium-potassium pump is like having to walk against a strong driving wind. The effort, needed for survival, requires tremendous energy. At rest, between one-quarter to one-half of the total energy needs of the body are taken up by the millions of sodium-potassium pumps in each of its trillions of cells. This goes to show that real numbers have real consequences. If the cell doesn’t have enough energy to power its millions of sodium-potassium pumps, it is as good as dead. But where does the cell get the energy it needs? Before you can begin to understand the answer to this question, you must first learn about enzymes and how they work in the body. We’ll look at them next time.
Image by Blausen.com staff. “Blausen gallery 2014”. Wikiversity Journal of Medicine. DOI:10.15347/wjm/2014.010. ISSN 20018762. (Own work) [CC BY 3.0 (http://creativecommons.org/licenses/by/3.0)%5D, via Wikimedia Commons.
Enzymes and Their Dynamic Role in the Cell
Howard Glicksman March 17, 2015 3:35 AM | Permalink
Editor’s note: Engineers and physicians have a special place among the thinkers and scholars who have elaborated the argument for intelligent design. Perhaps that’s because, more than evolutionary biologists, they are familiar in very practical ways with the challenges of designing or maintaining a functioning complex system on the order of a jet airplane, or the human body. With that in mind, Evolution News & Views is delighted to present this series, “The Designed Body.” Dr. Howard Glicksman practices palliative medicine for a hospice organization.
In this series so far, we’ve looked at what makes up the human cell and what it needs to do to stay alive. We learned that, because they constantly threaten to alter the cell’s chemical content and volume, the natural powers of diffusion and osmosis must somehow be combated. The cell has come up with an innovation to do exactly that. It has millions ofsodium-potassium pumps in its plasma membrane that constantly push sodium back out of the cell and bring potassium inside. While thus maintaining its chemical content, the cell is also able to control its volume by preventing water from entering by osmosis. To accomplish this task and all of its other vital functions, the cell must have enough energy.
It’s important to understand that every biochemical process in the body requires enzymes to work properly. So, before you can learn about how the cell gets the energy it needs to live, grow and work properly, you must first learn about enzymes.
Enzymes are special molecules (mostly proteins) that are made in the cell and help other molecules undergo chemical reactions when they come in contact with each other. When these reactions occur, energy is either released or used up, and different molecules are produced. Molecules are made up of atoms joined together by chemical bonds. There are very small molecules, like molecular oxygen (O2), which comprise two oxygen atoms joined together, and water (H2O), which is made up of two hydrogen atoms joined to one oxygen atom. There are also slightly larger molecules, like glucose (C6H12O6), a sugar that is made up of six atoms of carbon and oxygen joined to twelve atoms of hydrogen. And there are very large molecules, like carbohydrates, fats, and proteins, many of which are made up of hundreds or even thousands of atoms joined together.
When molecules meet up with each other they sometimes react. A reaction between molecules simply means that chemical bonds between atoms are created or destroyed. This usually causes some of the atoms in the reacting molecules to change places with each other to form different molecules. Some enzymes help destroy chemical bonds in larger molecules, to form smaller molecules. Other enzymes help create chemical bonds between smaller molecules, to make larger ones.
In this process energy may be released or used up. At the end of the reaction the enzymes are not altered, so they can continue to promote more reactions. Also, the total number of atoms present in the molecules that are produced at the end of the reaction is the same as there were in the molecules that reacted in the first place. In other words, in a chemical reaction no new atoms are created or destroyed, just the bonds between them. This often results in the release or use of energy, and the atoms involved changing partners to form different molecules.
The laws of nature determine how fast specific molecules will react with each other. But the addition of an enzyme makes this reaction take place much faster. By speeding things up enzymes help to produce many more new molecules, usually on the order of thousands or millions of times more, than what would otherwise happen in the same time frame. This is why enzymes are called catalysts. In fact, if our body were left to only the natural laws of chemistry, the thousands of reactions we need to help keep us alive would not take place fast enough and we would die.
There are thousands of different enzymes in the body. Each has a specific effect on a specific molecule. It is the precise shape and chemical nature of the enzyme that determines which molecules it works on and what type of reaction it catalyzes.
The first part of the chemical name of an enzyme usually indicates the molecule or class of molecules for which it speeds up reactions. The last part of its name usually ends in “ase”. For example, lactase is the enzyme that helps to break down lactose, the sugar in milk. A protease is a class of enzymes that helps to break down proteins that are made up of two or more amino acids bonded together.
The body often uses several specific enzymes in a specific order or pathway, like in a chain reaction. The first molecule undergoes a reaction catalyzed by the first enzyme, and one of the products of that reaction becomes the second molecule in the pathway. The second molecule, in turn, undergoes a reaction catalyzed by the second enzyme, and one of the products of that reaction becomes the third molecule in the pathway.
The third molecule undergoes a reaction catalyzed by the third enzyme, and one of the products becomes the fourth molecule in the pathway, and so on. This process continues until the required molecule is produced. If any one of the enzymes in the pathway were to be missing or not working properly, then not enough of the final product would be produced and life could hang in the balance.
It is important to understand that since enzymes themselves are made up of hundreds or thousands of atoms chemically bonded together, the laws of nature can affect their chemical stability and capacity to work properly. Things like temperature and hydrogen ion concentration can affect the chemical structure of enzymes. When any of these parameters falls out of the normal range, the enzymes in our body start to malfunction and so does our body. Serious deviations can even result in death. That is why our body must be able to control these and other vital parameters to allow us to survive within the laws of nature.
Now that you have a basic understanding of what enzymes are, why they’re important for life, and how they work, we can move to see how the cell uses enzymes to get the energy it needs to survive.
Image by Jkaeelwes (Own work) [Public domain], via Wikimedia Commons.