Respiration Flashcards
what is aerobic respiration
respiration in the present eof oxygen; has four stages glycolysis, link reaction, Krebs cycle, oxidative phosphorylation
what is anaerobic respiration
respiration in the absence of oxygen, first stage is glycolysis, produces 2 molecules of ATP (net)
what is a respiratory substrate
a molecule that can be broken down in respiration to release energy
what is hexose
a sugar containing 6C
what is glycolysis
breakdown of glucose into two molecules of triode phosphate, net gain of 2 ATP , formed by oxidative phosphorylation, two hydrogens removed and picked up by NAD to become reduced NAD, occurs in cytoplasm
describe the link reaction
pyruvate is decarboxylated so one carbon is removed to produced CO2, NAD is reduced to NADH and acetate is combined with coenzyme A to form acetyl coenzyme A, no ATP produced
what is the Krebs cycle
occurs in the matrix of the mitochondria, oxaloacetate joins with acetate to give citrate (6C) and releases coenzyme A, carboxyl groups are removed and hydrogen atoms too so the 4C compound is regenerated, cycle turns twice for each glucose molecule
what is oxidative phosphorylation
producing pyruvate from glucose, split into stages: activation of glucose by phosphorylation, splitting of phosphorylated hexose sugar, oxidation of triode phosphate, production of ATP
what is substrate level phosphorylation
when a phosphate group is directly transported from one molecule to another
what is chemiosmosis
the movement of H+ ions by facilitated diffusion using ATP synthase from an area of high conc. in the intermediate space to high conc. in the matrix
what is a coenzyme
a molecule which aids the function of an enzyme by transferring a chemical group
what is NAD
transfers hydrogen from one molecule to another
What is FAD
transfers hydrogen from one molecule to another
What is ATP
adenosine triphosphate , nucleic acid which is the energy-carrying molecule that provides energy for cell activity
What is phosphorylation
addition of phosphate group to a molecule
What is dehydrogenation
two hydrogens are removed and used to reduce NAD to form NADH which is later used to produce ATP, enzyme involved is called pyruvate dehydrogenase
Where is the cristae and what reactions occur here
mitochondria, site of chemiosmosis
Where is the matrix and what reactions take place here
mitochondria, Krebs cycle, link reaction
describe alcohol fermentation
occurs in yeast and produces ethanol, intermediate substance is ethanal, takes place in cytoplasm
describe lactate fermentation
occurs in mammals and produces lactate, intermediate product is pyruvate (as first stage is glycolysis), takes place in cytoplasm
what coenzymes are used in respiration
NAD, coenzyme a and FAD
what does coenzyme a do
transfer acetate rom one molecule to another
where does glycolysis take place and what type of process is it
cytoplasm of cells
anaerobic
equation for lactate fermentation
equation for alcohol fermentation
give two examples of respiratory quotients
RQ= volume of Co2 released/volume of o2 consumed
RQ= molecules of Co2 released/molecules of O2 consumed
