concept 9.1: catabolic pathways yield energy by oxidizing organic fuels

how does energy enter and exit an exosystem

enters as light from the sun and leaves as heat

what does photosynthesis generate

generates O2 and organic molecules

equation for photosynthesis

CO2+ H2O= organic molecules + O2

equation for cellular respiration

O2+ organic molecules = ATP +CO2 +H2O

how do catabolic pathways release energy

by breaking down complex molecules

is the breakdown of organic molecules exergonic or endergonic

breakdown of organic molecules is hydrolysis and exergonic

fermentation

a partial degradation of sugars that occurs without oxygen

aerobic respiration

consumes organic molecules and oxygen and yields ATP

anaerobic respiration

consumes compounds other than O2

cellular respiration

includes both aerobic and anaerobic respiration but is more often aerobic respiration, includes the sugar glucose

what does cellular respiration use as fuel

does not use protein, and uses fat and carbs because the body had more of it

where do aerobic processes occur in the cell

aerobic in mitochondria

where do anaerobic

anaerobic processes occur in the cytosol

how do cells regenerate their supply of ATP

from ADP and phosphate

what is a redox reaction

transfer of electrons during chemical reactions

oxidation

REMOVE electrons

reduction

ADDITION of electrons

where does the production of ATP come from

the break down of glucose

is oxidation exergonic/endergonic, -/+ delta G, spontaneous/nonspontaneous

oxidation is exergonic, -delta G, spontaneous

is reduction exergonic/endergonic, -/+ delta G, spontaneous/nonspontaneous

endergonic, +delta G, spontaneous

oxidation leads to what

loss of C-H or C-C covalent bonds

what does the oxidation of glucose result in

oxidation of glucose releases energy to form ATP

Reducing agent

becoming oxidized, electron donor, losing electron

oxidation agent

becoming reduced, gaining electron, electron acceptor

the transfer of electrons during chemical reactions does what

releases energy stored in organic molecules

how is ATP assembled

from ADP + PO4 using free energy from the oxidation of glucose

during cellular respiration what molecule is oxidized and what molecule is reduced

the furl/ glucose is oxidized, O2 is reduced

what makes a good source of high energy electrons

organic molecules with a lot of hydrogen are good sources of high energy electrons

what occurs fist after electrons are removed from organic compounds

electrons are first transferred to NAD+, a coenzyme

what is NAD +

nicotinamide adenine dinucleotide

what does NAD+ act as

functions as an oxidizing agent and becomes reduced when it accepts electrons

what is NADH

the reduced form of NAD+

what does NADH represent

stored energy that is later tapped to synthesize ATP

what does NADH do

passes the electrons to the electrons transport chain which is located within the mitochondrion

what does the electron transport chain do

passes electrons in a series of steps

what does O2 do inside of the electron transport chain

O2 pulls electrons down the chain in an energy yielding tumble, and that energy is used to regenerate ATP

why is O2 able to pull electrons

because it is very electronegative

what are the three stages of turning energy into glucose

1- glycolysis

2- the citric acid

3- oxidative phosphorlyation

glycolysis

breaks down one glucose molecule into two molecules of pyruvate

the citric acid cycle

completes the breakdown of glucose and pyruvate enters the mitochondrion

oxidative phosphorylation

accounts for most of the ATP synthesis and occurs in the mitochondria

what generates 90% of all ATP

oxidative phosphorylation powered by redox reactions

for each molecule of glucose the cell makes how many molecules of ATP during oxidative phosphorylation

one molecule of glucose can make up to 28 molecules of ATP