The higher the temperature is, the higher the rate of the enzyme reaction becomes, as it increases, and heat is produced. It has an optimum temperature of where it works best at 37 to 40 C, but after 40 C the enzyme gets denatured and no longer works properly, particularly in animal ones.
When the temperature rises, there are more energetic collisions between the enzymes within the reaction. The number of these per minute will also increase, along with the heat of the molecules.
Many experiments have been done in labs across the world, testing the results of enzyme activities. They have found some great answers, which help give proof to biology and how our body’s work as well as those of animals and plants.
Most enzyme reactions are often done below 40 C in order to give them a good efficiency and not denature them. If they get denatured, then they are damaged and no longer fit into each other to create a reaction.
Enzymes can be stored at 5 C or below, although some of them lose their effectiveness if they get too cold. This is why humans and most animals cannot get too cold or too hot, above 40 C, as it will denature many enzymes within the body, and therefore stop its functions.
This will lead to serious illness and even death. It is important to keep the body at the optimum temperature of around 37 C in order for them to work best, and keep it fit and healthy.
Temperature can affect a lot of different factors hence its effect on enzyme activity is very complex. It affects the speeds of molecules, the activation energy of the catalytic reaction and the thermal stability of the enzyme and substrate.
At low temperatures (say at around 0 centigrade) the rate of enzyme reaction is very slow. The molecules have low kinetic energy and collisions between them are less frequent and even if they do collide the molecules do not posses the minimum activation energy required for the reaction to occur. It can be said that the enzymes are deactivated at low temperatures.
An increase in temperature increases the enzyme activity since the molecules now possess greater kinetic energy. The rate of enzyme activity is highest between 0-40 centigrade and this increase is almost linear.
After 40 the rate of reaction starts to decrease. This is because the increase in temperature after 40 does not increase the kinetic energy of the enzyme but instead disrupts the forces maintaining the shape of the molecule. The enzyme molecules are gradually denatured causing the shape of the active site to change. Temperatures above 65 centigrade completely denature the enzymes.
There are some enzymes known as 'extremophiles' found in thermophillic organisms. They retain activity at 80 centigrade.
Enzymes are biological catalysts. They are specified to work at a certain temperature, and that temperature on which they work the fastest is known as their optimum temperature, which is usually 30-45 degree Celsius for most enzymes in the body. In the optimum temp. The activity increases due to the greater kinetic energy possessed by molecules (with greater temperature), which increases the rate of enzymes and substrates colliding and the substrates fitting into the enzymes. However, with the temperature exceeding the optimum limit, the enzyme starts to 'denature' (means its shape is distorted) due to the chemical bonds breaking in the enzyme. Consequently, the active sites are lost and the enzyme gets useless.
Increase and decrease in temperature affect the activity of the enzymes. Usually the activity f the enzymes is optimum at normal body temperature. At very low temperature the activity of the enzymes is minimum. Beyond 6o to 70 degree centigrade, usually their activity is permanently stopped de to the denaturation of enzymes.
The rate of enzyme-controlled reaction may increase with increase in temperature but up to a certain limit. All enzymes can work at their maximum rate at a specific temperature called optimum temperature.
Heat provides activation energy and therefore, chemical reactions are accelerated at high temperature. Heat also supplies kinetic energy to the reacting molecules, causing them to move rapidly. Thus the reactants move more quickly and chances of their collision with each other are increased. However, further increase in heat energy also increases the vibrations of atoms, which make up the enzyme molecule. If the vibrations become too violent, globular structure essential for enzyme activity is lost and the enzyme is said to be denatured.
Enzymes are proteins and it act as a biological catalyst ,ie it will increase the rate of a reaction without undergoing any reaction.Enzymes are highly sensitive to temperature and pH.Too high or low temperature or pH will cause the destruction of enzyme activity.So a enzyme to work properly,it should have a optimum pH and temperature.The optimum temperature for most of the enzymes in human body is 37 degree celicus.But optimum pH depends upon the cells. Eg:Pepsin is a enzyme in stomach and its optimum pH is 2
It increases the rate up to a point. 60 degrees Celsius is supposed to be an optimum level. Proteins such as enzymes will denature and become ineffective if the temperature is too high (100 degrees Celsius).
What is the effect of temperature on enzyme activity if the speed of the reaction with the supstrate is already maximum (Vmax)? Exp, if the maximum speed is observed at 20°C, and we bring the temperature up to 27°C?