Cell Biology Answers

What do you think will happen to living things if all enzymes will be deactivated for 24 hours?

Answer the blank: A certain protein can only act as a catalyst if it is linked with the B vitamin biotin. This protein is called _______________________ and biotin is its ______________________.

Answer the blank: In order for the enzyme lactase to catalyze the digestion of lactose into the monosaccharides glucose and galactose, lactose must first bind to the _____________________ of the enzyme.

Answer the blank: Based on where they perform their functions, the enzymes amylase and maltase in human saliva are classified as ________________________________.

Answer the blank: Many of the enzymes involved in photosynthesis aid in chemical reactions that remove electrons from the oxygen atoms in water and transfer these electrons to the carbon atoms in carbon dioxide. Based on the kind of reaction that they catalyze, these enzymes are classified as ______________________________.

Answer the blank: A particular chemical reaction will only proceed if the particles of its reactants possess energy that is greater than 250 kilojoules (kJ/mol). 250 kJ/mol is the ________________________ for this reaction.

Answer the blank: The binding of ATP with the enzyme pyruvate kinase results in this enzyme's failure to catalyze the last step in the breakdown of glucose during the process of glycolysis. In this situation, ATP acts as the ______________________________ of pyruvate kinase.

Answer the blank: The unstable compound that is formed when the disaccharide maltose binds with the active site of the enzyme maltase is called ___________________________.

Answer the blank: Pepsin is an enzyme present in gastric juice. In the stomach, it catalyzes the breaking down of proteins into shorter polypeptides. Therefore, proteins are the _________________ of pepsin.

Answer the blank: Destruction of the ozone layer takes place when its component ozone (O3) is converted into oxygen gas (O2) as shown by the following chemical equation O3 + O = 2O2

Although degradation of O3 happens naturally, there are some man-made substances that cause this process to take place at a rate which is harmful to the environment. One such substance is chlorofluorocarbon or CFC. In the presence of ultraviolet (UV) radiation, a chlorine (Cl) atom from CFC reacts with O3 and converts its to O2 at a faster rate. This is shown by the 2 equations below.

Cl + O3 = ClO + O2

ClO + O = Cl + O2

In this process, the chlorine atom acts as _________________________