quiz 2.2 Flashcards
the process by which chemical substances called nutrients are acquired from the environment and used in cellular activities such as metabolism and growth
nutrition
carbon, oxygen, hydrogen, nitrogen, sulfur, phosphorous, potassium ions, magnesium ions, calcium ions, iron 2+ and 3+
macronutrients needed in large quantities
what is so important about carbon
makes up 50% of microbial dry weight; is the backbone of all macromolecules (proteins lipids and sugars); bacteria can be classifies based on carbon source
metabolize organic compounds (amino acids, fatty acids, and sugars)
heterotrophs
metabolize inorganic compounds (CO2, carbon fixation; mineral deposits (CaCO3))
autotrophs (ex. cyanobacteria)
heavy or trace metals, Manganese, Nickel Zinc, Copper
micronutrients, needed in small quantities, inorganic sources
organic compounds that are essential cell components or precursor components that cannot be synthesized by the cell, ex amino acids, vitamins, and purines and pyrimidines
growth factors
what are 5 ways organisms source energy
chemoorganotrophs, chemolithotrophs, phototrophs, aerobes, and anaerobes
what do chemoorganotrophs use?
organic compounds like sugars
what do chemolithotrophs use?
inorganic compounds like hydrogen gas, sulfur, or hydrogen sulfide
what do phototrophs use?
light energy, oxygenic photosynthesis (produces O2, use chlorophyll or cyanobacteria) OR anoxygenic photosynthesis (e- is not water, use bacteriochlorophyll)
where do aerobes source energy?
energy is extracted from compounds int he presence of oxygen
where do anaerobes source energy?
energy is extracted from compounds in the absence of oxygen
describe free energy
the energy available to do work; calculating delta G; measured in KJ; if positive = exergonic; if negative = endergonic
delta G is negative, the rxn proceeds with the release of free energy and is catabolic (break down and releases energy)
exergonic
delta G is positive, the rxn requires energy to proceed and is anabolic (build up, required energy)
endergonic
define enzyme
protein catalyst
what else can act as an enzyme?
rRNA
how do enzymes affect activation energy
they lower the activation energy of a reaction and this increases the rate of the rxn -> substrates brought together at a specific site within the enzyme; aligns with he reactive group; places strain on specific bonds; creating the correct microenvironment
activation site
most important site; lined with binding points and necessary component for microenvironment
what are some factors that affect enzymes
temp and pH
what are some small nonprotein molecules that participate in catalysis
prosthetic groups (firmly attached, ex metals) and coenzymes (loosely associated, ex vitamins)
4 biochemical principles
- catalysis of metabolic reactions by enzymes or ribosomes 2. importance of oxidative-reduction reactions in energy conservation 3. the use of ATP to conserve energy released during most exergonic reactions so it can be used to drive endergonic reactions 4. organization of metabolic rxns into pathways and cycles
oxidized
lose electron (donor)
