Lec 5 & Chp 5 Flashcards
What is metabolism?
buildup & breakdown of nutrients within a cell
- provides energy
- sum of all chemical reactions that take place in an organism
What is a catabolic reaction?
breaks down molecules; provides energy & building blocks for anabolism; EXERGONIC
What is an anabolic reaction?
uses energy & building blocks to build complex molecules; ENDERGONIC
What are metabolic pathways?
sequences of enzymatically catalyzed chemical reactions in a cell
What is a catalyst?
substance that increases the rate of chem reaction
What are enzymes?
proteins that act as biological catalysts
How is ATP an intermediate between catabolism and anabolism?
the energy of catabolic reactions is used to drive anabolic reactions and the energy used for chemical reactions is stored in ATP.
What is collision theory?
chemical reactions occur when atoms, ions, and molecules collide
What is activation energy?
collision energy required for a chem reaction to occur
What is reaction rate?
frequency of collisions containing enough energy to bring about a reaction
What are some of the important enzymes and what do they do?
oxidoreductase - oxidation-reduction reactions
transferase - transfer functional groups
hydrolase- hydrolysis
isomerase - rearrangement of atoms
ligase - joining molecules; uses atp
apoenzyme - protein portion
holoenzye - apoenzyme + cofactor
What factors influence enzyme activity?
temp
pH
substrate concentration
inhibitors
What are competitive inhibitors?
fill the active site of an enzyme and compete w/ the substrate
What are noncompetitive inhibitors?
interact w/ allosteric site rather than active site
What are riboenzymes?
RNA that function as catalysts by binding to substrates and acting upon them
What is oxidation?
removal of electrons
What is reduction?
gain of electrons
What is redox reaction?
oxidation reaction paired w/ reduction reaction
Biological oxidations are often ____________.
dehydrogeneations
Why is glucose such an important molecule for organisms?
compounds that have many hydrogen atoms are highly reduced compounds containing a large amount of potential energy
How is ATP generated?
phosphorylation of ADP w/ the input of energy
How are electrons transferred from one electron carrier to another?
electron transport chain (system)
What are the 3 stages of carbohydrate catabolism?
glycolysis
krebs cycle
electron transport chain
What is glycolysis?
oxidation of glucose to pyruvic acid; produces ATP & NADH
What is chemiosmosis?
electrons pass down electron transport chain while protons are pumped across membrane
What is fermentation?
releases energy from oxidation of organic molecules
What are 4 different fermentations?
lactic acid fermentation: produes lactic acid
homolactic fermentation: produces lactic acid only
heterolactic fermentation: produces lactic acid and other compounds
alcohol fermentation: produes ethanol + CO2
What are the 3 requirements for ATP production?
- energy sources
- electron carriers
- final electron acceptors
How do we classify organisms based on their primary energy source, and based on their carbon source? (4 names)
phototrophs - light as energy
chemotrophs - oxidation-reduction reactions of in/organic compounds
autotrophs - carbon dioxide
heterotrophs - require organic carbon source
`What are the 4 different biosynthesis’?
polysaccharide
lipid
amino acid & protein
purine pyrimidine
