I understand the role of enzymes in chemical reactions but metabolism is the sum of all the reactions in a cell or in the body. So how do enzymes control metabolism? Can they change the number of reactions in a body or can enzymes just control the chemical reactions in the body?
If the definition of metabolism was chemical reactions that occur in the body, then I would understand how enzymes control metabolism, but the word 'sum' is confusing to me. I would really appreciate if somebody can explain this to me.
Thanks for reading.
Since Jiskha doesn't have a biology expert at this time, please try posting your question at this site.
http://www.biology-online.org/biology-forum/
In addition, be sure to make really good use of Khan Academy!
https://www.khanacademy.org/science/biology
Click on the Subjects link at the top, and then find the specifics you need within each topic.
Also, if they can change the number of reactions in a body, how?
Enzymes play a crucial role in controlling metabolism, despite not directly altering the number of reactions in the body. To understand this, let me explain.
Metabolism refers to the chemical reactions that occur in a cell or an organism's body. It involves various processes such as breaking down molecules (catabolism) and building up molecules (anabolism). Enzymes, on the other hand, are biological catalysts that facilitate and speed up these chemical reactions by lowering the activation energy required for a reaction to occur.
Enzymes control metabolism by regulating the speed and specificity of chemical reactions. They do this through various mechanisms:
1. Activation and Inhibition: Enzymes can be activated or inhibited by factors like temperature, pH, and the presence of specific molecules. This allows them to respond to the needs of the cell or body and adjust the rate of reactions accordingly. For example, when energy levels are low, enzymes involved in energy production may be activated to increase the breakdown of molecules for energy.
2. Substrate Specificity: Enzymes have specific binding sites that only bind to particular molecules called substrates. This specificity allows enzymes to select which reactions occur, as they will only act on their specific substrates. For example, enzymes involved in glucose metabolism will only bind to glucose molecules and not other unrelated molecules.
3. Regulation of Enzyme Production: Enzyme production can be regulated by various cellular mechanisms. For example, gene expression can be controlled to increase or decrease the production of specific enzymes, thereby influencing the rate of specific metabolic reactions. This provides a way for the cell or body to respond to changing conditions and adjust metabolism accordingly.
It's important to note that while enzymes play a crucial role in controlling metabolism, they don't control the overall number of reactions that occur in the body. The number of reactions is determined by the complexity of the organism and its physiological needs. Enzymes, however, ensure that these reactions occur efficiently and at the right time by speeding up the reactions and providing specificity.
In summary, enzymes control metabolism by regulating the speed, specificity, and availability of reactions in the body. While they don't change the number of reactions, they play a crucial role in maintaining the balance and efficiency of metabolic processes.