ch 6: cellular respiration + photosynthesis

what is cellular respiration?

the process by which cells produce energy, primarily in the form of atp.

what is atp and what is its role in cellular activities?

atp (adenosine triphosphate) is the main molecule powering cellular activities.

what happens when the bond between the second and third phosphate of atp is broken?

energy is released for cell work.

what is the 'dead battery' form of atp?

adp (adenosine diphosphate).

what is glycolysis and where does it occur?

glycolysis is the breakdown of glucose into two pyruvate molecules, occurring in the cytoplasm.

what are the products of glycolysis?

a net gain of 2 atp and 2 nadh molecules, plus the release of 2 carbon dioxide molecules.

what is the transition stage in cellular respiration?

the conversion of pyruvate into acetyl-coa, which prepares it for the krebs cycle.

what does the krebs cycle produce for each glucose molecule?

6 nadh, 2 fadh

, and 2 atp.

where does the electron transport chain take place?

in the inner mitochondrial membrane.

what is the role of oxygen in cellular respiration?

oxygen acts as the final electron acceptor in the electron transport chain.

how many atp molecules can be produced from one glucose molecule during cellular respiration?

approximately 38 atp molecules, depending on efficiency and cell conditions.

what are the waste products of cellular respiration?

carbon dioxide (co

) and water.

what is the difference between aerobic and anaerobic respiration?

aerobic respiration requires oxygen and produces more atp, while anaerobic respiration occurs without oxygen and produces only 2 atp per glucose.

what are the classifications of organisms based on their oxygen requirements?

obligate aerobes, facultative anaerobes, and obligate anaerobes.

why is cellular respiration significant for life forms?

it produces atp necessary for all cellular functions, enabling survival, growth, and maintenance.

what is the overall chemical equation for cellular respiration?

glucose (c6h{12}o6) + oxygen (6o2) \rightarrow carbon dioxide (6co2) + water (6h2o) + energy (atp).

what is the role of nadh and fadh_2 in cellular respiration?

they are electron carriers that transport high-energy electrons to the electron transport chain.

how is atp synthesized during the electron transport chain?

atp is synthesized by atp synthase, an enzyme that uses the energy from a proton (h^+) gradient across the inner mitochondrial membrane, a process known as chemiosmosis.

what is lactic acid fermentation?

a type of anaerobic respiration where pyruvate is converted into lactic acid, regenerating nad^+ for glycolysis. it occurs in muscle cells during strenuous exercise and some bacteria.

what is alcoholic fermentation and what role does yeast play?

alcoholic fermentation is a type of anaerobic respiration in which yeast converts pyruvate into ethanol and carbon dioxide, regenerating nad^+ for glycolysis.

what are the cristae?

the folds of the inner mitochondrial membrane, which increase the surface area available for the electron transport chain and atp synthesis.

what is the function of atp synthase?

it is an enzyme located in the inner mitochondrial membrane that uses the energy from the flow of h^+ ions (protons) across the membrane to synthesize atp from adp and inorganic phosphate.

what happens to pyruvate before the krebs cycle in aerobic conditions?

pyruvate undergoes oxidative decarboxylation, where it loses a carbon atom as co_2 and is converted into an acetyl group, which then combines with coenzyme a to form acetyl-coa.

what is the purpose of fermentation in anaerobic conditions?

to regenerate nad^+ from nadh, allowing glycolysis to continue producing a small amount of atp in the absence of oxygen.