Читайте также:
|
It's the measurement which determines the concentration of hydrogen ions H+ in a solution, and determines if the solution is acidic, alkaline or neutral.
Solutions with pH less than 7 are acidic, while those with pH more than 7 are alkaline. Solutions with pH equals 7 are neutral.
Fig. (12) pH measurement
à Indicators of pH has standard colours to determine the acidity or basicity of a solution and gives approximated numbers, while the digital devices give more accurate numbers.
Example of pH indicators:-
1- Litmus papers
2- Methyl orange
3- Phenolphthalein
pH and the activity of enzymes
à Enzymes are affected by pH because its composed of amino acids which contain acidic carboxyl groups COOH- and basic amine groups NH2.
à Each enzyme has its own pH on which it becomes most active, this degree of pH is called " Optimum pH"
à If the pH of an enzyme decreased or increases, its activity decreases gradually till it stops.
à Most enzymes works at pH of 7.4
Examples
- Pepsin enzyme works at acidic pH (less than 7)
- Trypsin enzyme works at basic pH (more than 7)
(For reading only) pepsin enzyme is secreted by stomach to help in the digestion of proteins, whereas trypsin enzyme is secreted by pancreas and poured in small intestine to digest proteins, too.
à Scientists discovered that proteins can be used in the treatment of many diseases and disorders in human body. These biological macromolecules were produced and used to treat some diseases, they are called Biopharmaceuticals
à It's hard to send medicines to target cells in human body, scientists solved this problems by discovering methods to send these medicines to target cells by using nanomaterials, which resulted in the creation of a new science called Nanopharmaceutics and these nano biological medicines were called Nanobiopharmaceutics
Metabolism: A group of biochemical reactions which occur within living organisms in order to build complex macromolecules from simple molecules, or break up molecules to get energy.
Anabolism: A process by which simple molecules are used to build complex macromolecules through a group of chemical reactions which consume energy.
Catabolism: A process which breaks some molecules to release energy from them.
Activation energy: The minimum energy required for a chemical reaction to occur.
Enzymes: Biological catalysts formed from proteins molecules which speed up chemical reactions occurring within living organisms.
Substrate: The substance on which enzyme work.
Active site: A stereoisomer which is responsible for enzyme work.
Power of hydrogen pH: The measurement of the concentration of positive hydrogen ions in solutions to determine their acidity or basicity.
Biopharmaceuticals: They are biological macromolecules which are used to treat some diseases.
Nanopharmaceutics: The science that studies and creates methods for sending medicine right to target cells accurately by means of nanomaterials.
Nanopharmaceuticals: They are biological macromolecules which are used as medicines to treat some diseases, they are being sent to target cells by means of nanomaterials..
Дата добавления: 2015-11-16; просмотров: 78 | Нарушение авторских прав
| <== предыдущая страница | | | следующая страница ==> |
| Simple enzymes | | | Answer only four questions |