Eating habits - 6th set Flashcards
Metabolism has a…
starting material, intermediate and end product pathways can be linear, branched or cyclical catabolic pathway
carbohydrate metabolism
- is the breakdown of sugar molecules to produce energy
- pertains mainly to glucose metabolism; preferred energy source for cells
- released energy is trapped for ATP synthesis
Two processes in carbohydrate catabolism
Cellular respiration (or respiration): complete breakdown of glucose to CO2 ; makes enormous amount of ATP Fermentation: partial oxidation of glucose; forms organic waste products; generates fewer ATP ( compared to respiration)
main difference in respiration break down of glucose…
in fermentation it is only partial - fewer atp molecules
catabolic aka catabolism
Ecatabolism - break down of larger molecules or substances into smaller units which causes a release of energy used to make atp. this is exergonic. ex respiration.
anabolic aka anabolism
smaller units are joined to form larger molecules. energy lost is from heat, some can be channeled to trap and form ATP molecule. this is endergonic. ex. photosynthesis or protein synthesis, cell wall synthesis. Input of ATP.
phosphorylation - can occur in 2 ways
substrate level phosphorylation - rich shares w/ poor.
oxidative phosphorylation - (during electron transport chain) oxygen used, reduced to water. ADP becomes ATP
Aerobic
uses oxygen - final electron acceptor is molecular oxygen
Anaerobic (respiration)
does not use oxygen - final electron acceptor is inorganic molecule other than molecular oxygen
Glycolysis
Glycolysis: step common to both processes of glucose catabolism - oxidation of glucose to pyruvic acid (3 carbon compound) 2 molecules/glucose of pyruvic- occurs in cytoplasm and few ATP molecules are made ( substrate level phosphorylation
glucose is a.___carbon compound
6 carbon compound - broken down to 2 molecules of 3 carbon pyruvic acid compound. 2 molecules of pyruvic acid generates 2 molecules of glucose - common in cytoplasm.
steps in respiration
transition reaction, kreb’s cycle, and electron transport chain
Transition reaction
links glycolysis to Kreb’s cycle
- acetyl coA is synthesized from pyruvic acid - (3 c compound) at the end of glycolysis.
pyruvic acid releases CO2, and at the same time coenzyme A is added, then it forms acetyl COA. important - connects end product that can go into Krebb cycle. (transition - no ATP, no NADH) - takes place in cytoplasm and decarboxylation (carbon released) occurs
kreb’s cycle
also called as tricarboxylic acid ( TCA) or citric acid cycle - oxidation of acetyl col A to CO2 - occurs in cytoplasm and generates the NADH and FADH2 (these are the carriers of H2). - few ATP molecules are made by substrate level phosphorylation (ADP gets Pi and makes ATP - cyclical metabolic reaction
electron transport chain
- FADH2 and NADH oxidation occurs via a series of electron carriers - energy released is used to generate many ATP via oxidative (called this bc it becomes re-oxidized) phosphorylation. Final electron acceptor is always an inorganic molecule in respiration - could be O, sulfate etc. when its sulfate, gets reduced to hydrogen sulfide. Nitrate (NO3) can be terminal E acceptor, and it forms nitrite, then gets reduced to nitrous oxide, then reduced to N2 gas. some use carbonate, accepts E and forms methane gas. - archae methanobacterium. if it’s O, it’s always reduced to water.
Dehydrogenation
removal of hydrogen atom ( proton and electron)
