Ch. 8: Microbial Metabolism Flashcards
metabolism
used to describe all of the chemical reactions inside a cell
the 2 metabolic pathways
- anabolic
- catabolic
anabolism
refers to endergonic reactions (require energy) involved in biosynthesis, converting simple molecular building blocks into more complex molecules
catabolism
refers to exergonic reactions (spontaneous & release energy) that break down complex molecules into simpler ones
chemotroph classifications
- chemoautotrophs
- chemoheterotrophs
phototroph classifications
- photoautotrophs
- photoheterotrophs
autotrophs
organisms that convert inorganic CO2 to organic carbon compounds
heterotrophs
rely on more complex organic compounds as nutrients that are initially provided by autotrophs
phototrophs
get energy from light for electron transfer
chemotrophs
obtain energy for electron transfer by breaking chemical bonds
the 2 types of chemotrophs
- organotrophs
- lithotroph
organotroph
chemotrophs that obtain energy from organic compounds
- example: humans, fungi
lithotroph
chemotrophs that get energy from inorganic compounds
- unique to micro world
chemoautotrophs
- energy source: chemical
- carbon source: inorganic
- examples: hydrogen, nitrogen, sulfur, iron, & carbon monoxide-oxidizing bacteria
chemoheterotrophs
- energy source: chemical
- carbon source: organic compounds
- examples: all animals, most fungi, protozoa, bacteria
photoautotrophs
- energy source: light
- carbon source: inorganic
_ examples: all plants, algae, cyanobacteria, green & purple sulfur bacteria
photoheterotrophs
- energy source: light
- carbon source: organic compounds
- examples: green & purple nonsulfur bacteria, heliobacteria
oxidation reactions
reactions that remove electrons from donor molecules, leaving them oxidized
reduction reactions
reactions that add electrons to acceptor molecules, leaving them reduced
redox reactions
oxidation & reduction occur together, name for the pair of reactions
electron carriers
molecules that bind to & shuttle high energy electrons between compound pathways
nicotinamide adenine dinucleotide (NAD)
nicotine adenine dinucleotide phosphate (NADP)
flavine adenine dinucleotide (FAD)
NAD+/NADH
ATP
energy currency of cell, used to fulfil any energy need of the cell
ADP
formed when 2nd phosphate added to AMP
high-energy phosphate bonds
bonds between phosphate groups
dephosphorylation
loss of a phosphate group; energy released to drive endergonic reactions
catalyst
a substance that helps speed up a chemical reaction