human body is called the biochemical factory totally in vain.After all, every minute of it there are thousands, hundreds of thousands of oxidation, cleavage, recovery and other reactions.What allows them to proceed with such great speed, providing each cell with energy, food and oxygen?
concept of catalysts
As in inorganic and organic chemistry are widely used special substance capable of accelerating chemical reactions in thousands, and sometimes millions of times.The name of these compounds - "catalysts."In inorganic chemistry is metal oxides, platinum, silver, nickel and others.
Their main action - the formation of complexes with members of the temporary reaction by lowering the activation energy of the process is several times faster.Thereafter, the complex decomposes and can be deduced from the scope of the catalyst in the same qualitative and quantitative composition as the prior process.
There are two variants of catalytic reactions:
- homogeneous - the accelerator and the participants in the same state of aggregation;
- heterogeneous - the accelerator and the participants in different states, there is the interface.
In addition, there is the opposite of the effect of the compound - inhibitors.They are aimed at slowing down the necessary reactions.For example, they can reduce the amount of time on the formation of corrosion.
biological catalysts are inherently different from the inorganic, and there are several specific characteristics.Therefore, in other living systems catalysis.
Enzymes - what is it?
proved that if the action of special substances that accelerate certain processes are not carried out within living systems, it is usually in the stomach to digest the apple would be about two days.For that amount of time would begin the processes of decomposition and decay products of intoxication.However, this does not happen, and the fruit has fully processed and a half hours.Performed are biological catalysts that are abundantly present within each organism.But what are they and what is the basis such action?
biological catalysts of protein nature - it ferments.Their base - the complex structural organization, possessing a number of specific properties.Simply put, this is a unique protein that can reduce the activation energy of the processes in living organisms and implement them at a rate exceeding the usual values of a few million times.
There are many examples of such molecules:
- catalase;
- amylase;
- oxidoreductases;
- glucose oxidase;
- lipase;
- invertase;
- lysozyme;
- protease and others.
Thus, we can conclude that the enzymes - biological catalysts are protein nature, which act as powerful accelerators, allowing thousands of processes in living organisms at very high speeds.Their action is based on the digestion, oxidation, reduction.
similarities and protein inorganic catalysts
enzymes as biological catalysts have a number of properties similar to inorganic.To those include the following:
- Quicken only thermodynamically possible reactions.
- not affect the displacement of the chemical equilibrium in the equilibrium systems, and the same speed both forward and reverse.
- As a result, in the reaction are the only products, the catalyst is not among them.
However, in addition to similarity, there are also features of the enzymes.
differences depending on the nature
biological catalysts have several specific features:
- high degree of selectivity.That is one protein is able to activate only a specific reaction or a similar group.The most common work scheme "enzyme - substrate of the process."
- extremely high degree of activity, because some types of proteins are able to accelerate the reaction millions of times.
- Enzymes are highly dependent on environmental conditions.Show activity only in a certain temperature range.It is also strongly influenced by the pH.There is a curve showing the values of the minimum, maximum and optimum performance for each enzyme.
- There are special compounds called effectors, that are able to inhibit the biological nature of the catalyst, or, on the contrary, have a positive impact on them.
- substrate on which the enzyme works, should be strictly specific.There is a theory, which is called the key and lock.It describes the mechanism of action of the enzyme on the substrate.Catalyst, like a key, embedded in the substrate with their active center, and the reaction begins.
- After the process the enzyme is partially or completely destroyed.
Thus, it is clear that the value is extremely large protein catalysts for living organisms.However, their action is subject to certain rules and confined environment.
study of catalysis school
As part of the curriculum studied as catalysts in the chemistry and the biology.In chemistry lessons are studied in terms of materials used for industrial syntheses, receive a wide variety of products.In biology class is considered biological catalysts.Grade 9 involves the study of molecular biology and biochemistry fundamentals.Therefore, it is at this level of education, students obtain basic knowledge of how enzymes of active substances in the bodies of living creatures.
At lessons conducted experiments confirming the reactivity of these substances in certain temperature ranges and pH:
- investigation of the effects of hydrogen peroxide as a catalyst for crude and boiled carrots;
- impact on meat (raw and heat-treated), potatoes and other products.
enzymes in the human body
Each student, who went quite educated and middle-level education abroad, he knows how called biological catalysts.Enzymes in the body have a strictly specific specialization.Therefore, for each process can be called its catalyzing agent.
For all the enzymes of the body can be divided into several groups:
- oxidoreductases, such as catalase and alcohol dehydrogenase;
- transferase - Kenaz;
- hydrolases important for the digestion: pepsin, amylase, lipoprotein lipase, esterase and the like;
- ligase such as DNA polymerase;
- isomerase;
- lyase.
Since all of these compounds are protein in nature, as well as a complex of vitamins in the composition, the temperature rise is fraught denaturing the structure, and hence cessation of all biochemical reactions.In this case, the body close to death.Therefore, the heat required to bring down the body during illness.
Using protein catalysts in the industry
Most enzymes are used in various industries:
- chemical;
- textile;
- food.
On the shelves you can see the cleaners and detergents containing enzymes - this is the enzymes that improve the quality of washing.
What are biological catalysts?
difficult to overestimate their importance.After all, they not only allow living organisms to live, breathe, eat, exercise metabolism, but also give us the opportunity to destroy the industrial waste, receive medication to protect and preserve their health and the environment.
