Metabolism and Growth Flashcards
metabolism
chemical reactions designed to break down substances to release energy OR reactions that use energy to build new substances
catabolic pathway
breaking down
anabolic pathway
building up
amphibolic pathway
breaking down and building up
exergonic reactions
releasing energy
endergonic reactions
using energy
metabolic currency
ATP (adenosine triphosphate)
redox reactions
oxidation reactions and reduction reactions
oxidation
loses an electron, gains a positive charge
reduction
gains an electron, gains a negative charge
coenzyme
electron taxi
stages of cell respiration
- glycolysis
- Krebs cycle
- electron transport chain
prokaryotic cell
glycolysis and krebs in cytoplasm
ETC in plasma membrane
eukaryotic cell
glycolysis in cytoplasm
krebs and ETC in mitochondria
glycolysis
“splitting of sugar”
net gain: 2 ATP and 2 NADH
makes: 2 molecules pyruvate
Krebs cycle
happens 2x per glucose molecule
release carbon through CO2
makes TONS of taxis
electron transport chain
net gain: 34 - 35 ATP
shuffle electrons to get protons out
protons reenter to build ATP (ATP synthase)
chemiosmosis
movement of ions across a semipermeable membrane, down electrochemical gradient
aerobic terminal electron acceptor
oxygen
anaerobic terminal electron acceptor
something other than oxygen
nitrogen fixing bacteria terminal electron acceptor
nitrate
methanogens terminal electron acceptor
carbonate
sulfate reducers terminal electron acceptor
sulfate
does respiration use the electron chain
yes
does fermentation use the electron chain
no
fermentation uses
only glycolysis
exoenzymes
secrete enzymes to break down nutrients to get into cells
lipids are broken down by
lipases
proteins are broken down by
proteases and peptidases
nucleic acids are broken down by
nucleases
times fermentation is used in the body
using too much oxygen
exercise
photosynthesis
sunlight as energy
carbon fixation
heterotrophs
harvesting energy from biological molecules that are eaten or obtained
autotrophs
make own molecules
photoautotroph
use light for energy
chemoautotroph
chemical energy in molecules for energy
does metabolism influence growth rate
yes
how do bacteria replicate
binary fission
generation time
growth time/number of generations
growth phases
- lag phase
- log phase
- stationary phase
- death phase
lag phase
cells adjust to environment
log phase
exponential cell growth
stationary phase
cells dividing = cells dying
death phase
more cells dying than dividing
reactive oxygen species (ROS)
TOXIC
steals electrons from other things in cells
how to aerobes deal with ROS
enzymes that detoxify
do anaerobes deal with ROS
not really
obligate aerobes
require oxygen, catalase-positive
obligate anaerobes
cannot tolerate oxygen, catalase-negative
facultative anaerobes
grow best with oxygen but do not need it, catalase-positive
aerotolerant anaerobes
tolerate but do not use oxygen, catalase-positive
microaerophiles
use small amounts of oxygen, have small amounts of catalase
can bacteria regulate internal temperature
no
what happens if bacteria is not at optimal temperature
protein denaturing
reactions slow down
can bacteria regulate internal pH
to a degree, have optimal range
acidophiles
proton pumps/specialized membranes to protect enzymes
neutrophiles
most bacteria
alkaliphiles
enrich plasma membrane with acidic compounds
high-salt conditions
stress on microbial water balance
plasmolysis
water rushes out of cell
halophiles
microbes tolerate conditions up to 35% salt
extremophiles
organisms that live in extreme conditions