Chemistry SCC 10/2011
Quiz yourself by thinking what should be in
each of the black spaces below before clicking
on it to display the answer.
Help!
|
|
||||
|---|---|---|---|---|---|
| enzyme | a protein molecule that catalyzes chemical reactions without itself being destroyed or altered
🗑
|
||||
| catalyst | a substance that increases the rate of a chemical reaction but is not consumed or changed by it.
🗑
|
||||
| substrate | a substance upon which the enzyme acts
🗑
|
||||
| denaturation | the partial or total alteration of the structure of a protein without change in covalent structure by the action of certain physical procedures or chemical agents. Any disruption of the protein structure that is accompanied by a loss of activity
🗑
|
||||
| cofactor | nonprotein molecules that must bind to a particular enzyme before a reaction occurs (natural reactant – usually a metal ion or a coenzyme)
🗑
|
||||
| coenzyme | a diffusible, heat-stable substance of low molecular weight that when combined with an inactive protein called an apoenzyme forms an active compound or a complete enzyme called a holoenzyme
🗑
|
||||
| apoenzyme | the protein part of an enzyme
🗑
|
||||
| prostheticgroup | the coenzyme bound tightly to the enzyme
🗑
|
||||
| holoenzyme | the functional compound formed by the combination of an apoenzyme and its appropriate coenzyme
🗑
|
||||
| zymogen | Some enzymes, mostly digestive enzymes, are originally secreted from the organ of production in a structurally inactive form
🗑
|
||||
| activation energy | the energy required for a molecule to form an activated complex; in an enzyme-catalyzed reaction, corresponds to the formation of the activated enzyme substrate complex
🗑
|
||||
| enzyme-substrate complex (E-S) | a molecule of substrate is bound to the active center of the enzyme molecule
🗑
|
||||
| active site | where the initial binding of substrate and enzyme occurs
🗑
|
||||
| absolute specificity | meaning that the enzyme combines with only one substrate and catalyzes only the one corresponding reaction
🗑
|
||||
| group specificity | they combine with all substrates containing a particular chemical group
🗑
|
||||
| first-order kinetic reaction | a reaction in which the rate of reaction is proportional to the concentration of substrate
🗑
|
||||
| zero-order kinetic reaction | a reaction in which the rate is independent of the concentration of substrate, and depends on enzyme concentration only
🗑
|
||||
| activator | Inorganic cofactors, such as chloride or magnesium ions; They increase the catalytic activity of an enzyme when it binds to a specific site
🗑
|
||||
| inhibitor | interfere with the reaction, decrease the rate of reaction; can be either reversible or irreversible
🗑
|
||||
| uncompetitive inhibitor | binds to the enzyme-substrate complex so that increasing substrate concentration results in more ES complexes to which the inhibitor binds and thereby increases the inhibition so there is no product.
🗑
|
||||
| competitive inhibitor | binds to the active site of an enzyme and competes with substrate for the active site
🗑
|
||||
| noncompetitive inhibitor | binds an enzyme at a place other than the active site so no competition between inhibitor and substrate, examples are heavy-metal ions such as lead and mercury
🗑
|
||||
| Fixed time reaction | the amount of change produced by the enzyme is measured after the reaction is stopped (usually by inactivating the enzyme with a weak acid) at the end of a fixed time interval and a measurement is made of the amount of reaction that has occurred
🗑
|
||||
| continuous monitoring method | the reaction is monitored continuously, usually of absorbance change every 30 or 60 seconds. Continuous measurements are preferred because any deviation from linearity is readily observable
🗑
|
||||
| isoenzyme | one of a group of related enzymes catalyzine the same reaction but having different molecular structure and characterized by varying physical, biochemical, and immunological properties; subunit of the enzyme
🗑
|
||||
| NAD | nicotinamide adenine dinucleotide, example of a coenzyme
🗑
|
||||
| NADP | nicotinamide adenine dinucleotide phosphate, example of a coenzyme
🗑
|
||||
| Two-substrate reaction | more than one substrate yields more than one product and the concentrations of both substrates affect the rate of reaction
🗑
|
||||
| six classes of enzymes : | a. Oxidoreductases
b. Transferases
c. Hydrolases
d. Lyases
e. Isomerases
🗑
|
||||
| What are enzymes composed of | Proteins
🗑
|
||||
| What factors influence the actions of enzymes | - Substrate concentration
- Enzyme concentration
- Temperature
- pH
- activators
- inhibitors
🗑
|
||||
| What unit of measurement (activity) is used to express enzyme concentration | International Unit -(U/L)
Katal (mol/s) -Katals per liter (Kat/L).
🗑
|
||||
| How does temperature affect enzyme-catalyzed reactions? At what temperature are MOST enzyme catalyzed reactions performed? | optimal is 37°C; rate of an enzymatic reaction is proportional to its reaction temperature, until the temperature is high enough to denature the protein composition of the enzyme
🗑
|
||||
| At what pH are MOST enzymes optimally active? | Optimum pH is where the reaction rate is the fastest, must look at the pH activation curve for each enzymes optimum pH.
🗑
|
||||
| What enzymes and isoenzymes do we associate with the heart and MI's (myocardial infarction)? | CK, CK isoenzymes, LDH, LDH isoenzymes, AST, Troponin-I
🗑
|
||||
| What enzymes and isoenzymes do we associate with the liver and hepatic disease | AST, ALT, GGT, ALP, LDH (LDH-5), and 5’-NT
🗑
|
||||
| What enzyme and isoenzyme is associated with bone disorders? | ALP, ALP isoenzymes, ACP
🗑
|
||||
| Which enzymes are associated with pancreatic disease | AMS, LPS
🗑
|
||||
| Which enzyme is associated with prostate disease | ACP
🗑
|
||||
| Which enzymes and isoenzymes are associated with muscle disorders | CK, CK-MM, AWST, LDH (LD4 & LD5)
🗑
|
||||
| List the isoenzymes of CK and identify the tissue location of each. | CK-BB – brain
CK-MM – skeletal muscle
CK-MB – cardiac muscle (used in diagnosis of MI)
🗑
|
||||
| List the isoenzymes of LD/LDH and identify the tissue source of each. | LD-1 & LD-2 – cardiac muscle and RBCs
LD-3 – lungs and spleen
LD-4 & LD-5 – liver and skeletal muscle
🗑
|
||||
| What is the effect of hemolysis on MOST enzyme reaction tests | Falsely elevated results
🗑
|
||||
| What is the specimen of choice for most enzyme tests | Serum
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Created by:
CZUPAN
Popular Chemistry sets