cell metabolism
No description yet. This curated deck is ready for daily study.
Card preview (24)
types of metabolism pathways
catabolic - breaks down bigger molecules into smaller molecules anabolic - synthesises molecules that form the cell
homeostasis
regulation of the internal environment pH, temperature, blood glucose
how is food metabolised to generate energetically useful compounds?
• food molecules are broken down into small carbon units in the cytosol • molecules are then transported into the matrix of the mitochondrion • further broken down into CO2 and NADH • electrons from deprotonation of NADH enter the electron transport chain • the electron transport chain produces a proton gradient, allowing energy to be stored as chemical energy
mitochondria use ___ and ___ as fuel and where do these fuels come from
both pyruvate and fatty acids pyruvate comes from glucose and other sugars, fatty acids come from fats
main function of NADH in the electron transport chain
it carries electrons around and provides electrons to the electron transport chain
is hydrolysis energetically favourable
yes
is polymerisation energetically favourable
no
whether a reaction is energetically favourable or not can be determined by
Gibbs free enery G = H - TS
3 molecules that store energy as chemical bond energy
ATP, NADH, NADPH
products from breakdown of ATP
ADP, Pi (inorganic phosphate) and H2O
pathway (3 steps) from sugars/polysaccharides to form acetyl CoA
sugars/polysaccharides –> glucose –> pyruvate –> acetyl CoA
how much energy does the hydrolysis of ATP yield
11-13 kcal/mol; very negative G value
pathway from fats to acetyl CoA
fats –> fatty acids –> acetyl CoA
where do fats and sugars convert to acetyl CoA
in the mitochondrion matrix
how fat is stored in animals is it a long/short term storage of energy?
store fatty acids as fat droplets composed of water insoluble triacylglycerols in adipocytes (specilised fat cells) long term storage
how sugar is stored in animals long/short term storage
stored as glycogen in the cytoplasm of cells in a chain of glucose short term storage
reactants and products of glycolysis
glucose –> 2 pyruvate, 2 NADH, 2 H+, 2 ATP, 2H2O
name of pathway, reactants and products of ATP production in anaerobic conditions
fermentation glucose –> pyruvate -(in mitochondria)-> ATP, CO2 and ethanol
where in the cell does glycolysis take place
cytoplasm
products from the breakdown of a fatty acid
acetyl CoA, NADH, FADH2
major products of the citric acid (CA) cycle
CO2 and high energy electrons in NADH
what subcellular organelles do prokaryotes and eukaryotes use to produce ATP
prokaryotes use their plasma membrane eukaryotes use mitochondria
is sugar or fat a richer source of energy
fat
2 stages of chemiosmotic coupling
• high energy electrons derived from the oxidation of food molecules are transferred along electron carriers, pumping protons and generating an electrochemical proton gradient • electrochemical gradient is used to generate ATP with ATP synthase by harnessing the proton gradient