Question | Answer |
What is life built on | chemical reactions; transofrming energy from one form to another |
What is the first law of thermodynamics | energy cannot be created or destroyed, only transoformed |
What do living systems need to continually acquire and transform to remain alive | energy |
what is free energy | the energy available in a system to do work |
What is the 2nd law of thermodynamics | Every time energy is transformed the entropy (disorder) of the universe increases |
How do organisms maintain order? | by coupling cellular processes |
coupling cellular prcesses | |
What are metabolic reactions that can form bonds between molecules | dehydration synthesis; synthesis; anabolic reactions; endergonic |
metabolic reactions that can break bonds between molecules | hydrolysis; digestion; catabolic reactions; exergonic |
energy released | exergonic; downhill |
energy input | endergonic; uphill |
What does breaking down large molecules requie? | an initial input of energy; activation enery |
large biomolecules are | stable and must absorb energy to break bonds |
Why don't reactions just happen spontaneously | because covalent bonds are stable |
activation energy | the amount of energy needed to destablize the bonds of a molcule |
how does a cell get help for reactions | enzymes |
Organisms are? | endergonic systems |
What do we need energy for? | synthesis; reproduction; active transport; movement; temperature regulation |
What happens when there is insufficient free energy production? | disease or death, decline of a population; complexity in an ecosystem |
Formula of free energy | ΔG = ΔH - TΔS. |
change in enthalpy | - = exothermic, + = endothermic |
change in entropy | - = entropy decrease, + = entropy increase |
spontaeous reactions | continue once they are initiated |
non-spontaneous reactions | require continual input of energy to continue |
reaction that are always spontaneous/exergonic | exothermic reactions that increase entropy |
always non-spontaneous/endergonic | endothermic reactions that decrease entropy |
why do we have ATP | need a short term energy storage molecule |
ATP | modified nucleotide that is energy |
How does ATP store energy? | stored energy in each PO4 bond (phosphate group attached) |
What makes ATP an excellent energy donor? | instability of its P bonds |
How does ATP transfer energy? | |
What is the enzyme that phosphorlates | kinase |
we can't store ATP | too reactive and only short term energy storage |
Why do cells make ATP if it takes a lot of time | chemical, mechanical and tranport work |
Why to we need energy | to run reactions |
how do you measure metabolic rate | find amount of heat loss or O2 consumes or CO2 produced |
thermoregulation | eat regulation in mammals often involves the integumentary system (insulation behavioral responses, etc...) |
Where is energy stored | organic molecules |
Where is harvested energy stored | glucose |
cellular respiration | catabolism of glucose to produce ATP |
How do we harvest energy from fuels? | digest large molecules into smaller ones; break bonds and move electrons from one molecule to another |
As electrons move they carry what with them | energy |
how do electrons move | |
redox reactions | coupling oxidation and reduction |
oxidation | loss of electron |
reduction | gain of electron |
what releases energy as breakdown molecules | redox reactions |
what is the most electronegative atom in biology? | oxygen |
what is oxidized in respiration | glucose |
what is reduced in respiration | oxygen |
How are electrons moved in respiration | electron carriers move electrons by shuttling H atoms around |
anaerobic respiration | glycolysis; the breaking down of glucose; in cytosol |
aerobic respiration | in mitochondria; pyruvate oxidation; kreb's cycle; etc |
What's the point? | to make ATP |
glycolysis | breaks down 6C glucose to 2 3C pyrvate |
ATP generated glycolysis | 2 ATP |
How is NADH recycle to NAD+ | another molecule must accept H from NADH; anaerobic respiration (fermentation) |
Why is pyruvate a branching point | can be used for fermentation or kreb's cycle |
kreb's cycle -what happens to pyruvate | oxidized to acetyl COA |
kreb's cycle occurs (#) | 2x for each glucose molecule |
Krebs produces | 8 NADH, 2 FADH2, 2 ATP, 6 CO2 |
Why glycolysis and krebs | value of NADH and FADH2 |
ETC | series of molecules built into inner mitochondrial membrane; mostly transport (integral) proteins |
ETC electron tranport | transport of electrons down ETC linked to ATP synthesis |
chemiosmosis | H atoms move across inner membrane to intermembrane space |
What pulls the electrons down the ETC | oxygen |
each carrier | more electronegative |
ATP synthase | enzyme to make ATP in ETC; only channel permeable to H+; powered by H+ |
metabolism | coordination of digestion & synthesis by regulation enzyme |
feedback inhibition | regulation & coordination of production; self-limiting; final product is inhibitor of earlier step |
where does CO2 enter into leaves | stomates |
Where does photosynthesis occur | chloroplasts |
pigment in chloroplasts | chlorophyll |
How does photosynthesis get energy? | absorbing wavelengths of light |