Chapter 10 Key Terms Flashcards
Activation Energy
The minimum amount of initial energy required to start a chemical reaction
Active site
The place on the surface of an enzyme molecules where substrate molecules attach
ADP (Adenosine diphosphate)
A low energy compound, converted to Adenosine triphosphate for energy storage when it gains a phosphate group
Aerobic respiration
A type of cellular respiration that takes place in the cytosol and mitochondria in the presence of oxygen
Catabolic reaction
The reactions in living things that invlolve the breakdown of complex molecules into simpler ones
Catabolic reaction
The reactions in living things that invlolve the breakdown of complex molecules into simpler ones and usually release energy from breaking bonds
Catalyst
A substance that speeds up chemical reactions without being used up in the reaction
Cellular respiration
A biochemical process that occurs in the cytosol and mitochondria
- metabolises organic compounds (glucose) aerobically in the form of ATP,
- Products of anaerobic, respiration vary between organisms (plants, yeast, bacteria)
Coenzyme
A small, non-protein organic substance that must be present in addition to an enzyme to catalyse a certain reaction.
Cofactor
A small, inorganic substance that must be present in addition to an enzyme to catalyse a certain reaction
Denatured
(Proteins) Structurally changed by factors such as pH and temperature
- If the protein is an enzyme, the change destroys the shape of the active site and results in a loss of function
Endergonic Reaction
An energy-requiring chemical reaction
Enzyme
A specific biological catalyst that increases the rate of chemical reaction without being altered itself by lowering the amount of energy required for the reaction to proceed
Enzyme - Substrate complex
A substance formed when an enzyme molecule and a substrate molecule join
Exergonic reaction
A reaction that releases energy
Glycolysis
A energy-yielding process occurring in cell cytosol
- Glucose is partially broken down to pyruvate in enzyme reactions that do not require oxygen
- First stage of cellular respiration produces two ATP molecules
Grana
A stack of thylakoid membranes in a chloroplast that contain chlorophyll
Induced-fit model
A model suggesting that the shape of an enzyme’s active site undergoes specific changes
- Induced by the substrate, to achieve a high degree of specificity with the substrate
Inhibitor
A substance that competes with a substrate for an enzyme’s active site
Lactic acid fermentation
A form anaerobic respiration
- occurs in animal cells and some anaerobic bacteria
- Glucose is converted to lactic acid
Light-dependent stage
The first stage of photosynthesis
- Requires light energy, which is absorbed by chlorophyll
- Water molecules split to produce oxygen and hydrogen ions, and ATP
Light-independent stage
The second stage of photosynthesis
- Carbon dioxide, hydrogen ions and ATP produce a carbohydrate
Lock-and-key-model
A model suggesting that the shape of is an exact fi to the shape of an enzyme’s active site
Metabolism
The sum of all biochemical reactions in an organism; can be divided into two types, catabolic reaction and anabolic reactions
Phosphorylation
A process when a bond forms between an available phosphate group an ADP, producing ATP
Photosynthesis
Biochemical process
- Uses light energy to synthesise organic compounds
- light-dependent and light-independent reactions occur at different sites in chloroplast
Psychrophile
An organism that lives in extremely cold conditions
Pyruvate
Three-carbon compound that is the end product of glycolysis
Stroma
Jelly like, semi fluid interior of a chloroplast
Substrate
A reactant on which an enzyme acts
Thermophile
An organism that lives in high-temperature environments
Thylakoid membrane
Interconnected, folded membranes within chloroplasts
