Respiration Flashcards
Needs for energy:
- movement(muscle contraction)
- active transport
- anabolic reactions (DNA replication and protein synthesis)
- maintenance of body temperature
The equation for respiration:
C6H12O6 + 6O2 = 6H2O + 6CO2
Respiratory Quotient is the ratio…
of CO2 given out to the O2 consumed. RQ = vol. of CO2 / vol. of O2
Carboxyl group is…
-COOH and it is always in acids. The H easily dissociates forming H+ ion, lowering the pH.
Respiration is…
the sequential breakdown of glucose to synthesise ATP.
Stages of respiration:
- Glycolysis (cytoplasm)
- Link reaction (matrix)
- Krebs cycle (matrix)
- Oxidative phosphorylation (cristae)
During glycolysis, glucose (6C) is converted into…
2 pyruvates, each containing 3C
(Glycolysis) Glucose is…
phosphorylated by ATP to form fructose 1,6, bisphosphate.
(Glycolysis) Fructose 1,6, bisphosphate is…
enzamically broken down into 2 triphosphates, each containing 3C
(Glycolysis) Triphosphate is…
oxidised to pyruvate with 2 ATP and reduced NAD produced.
(Link reaction) Pyruvate moves by…
active transport into mitochondrial matrix
(Link reaction) In the mitochondrial matrix, pyruvate is…
decarboxylated (CO2 removed), dehydrogenated (H removed, forming reduced NAD) and joined to Coenzyme A (CoA)
Link reaction produces…
acetyl CoA, containing 2 carbons.
(Krebs cycle) The acetyl…
CoA joins oxaloacetate(4C) to make citric acid(6C). The enzyme CoA is recycled.
(Krebs cycle) The citric acid loses…
1 carbon (CO2) at a time until it produces oxaloacetate (4C) again
(Krebs cycle) Decarboxylation and…
dehydrogenation produces reduced NAD and reduced FAD.
(Oxidative phosphorylation) is also called…
the electron transport chain.
(Oxidative phosphorylation) The process of addition of…
phosphate to ADP making ATP in the presence of oxygen.
(Oxidative phosphorylation) Carrier proteins are…
embedded in the cristae.
(Oxidative phosphorylation) Electrons from…
NAD and FAD are passed from carrier to carrier. The energy released is used to actively pump protons across the membrane.
(Oxidative phosphorylation) Protons pass back through…
the membrane by facilitated diffusion, through ATPase proteins which synthesises ATP
(Oxidative phosphorylation) H+ ions then bond…
with O2 forming H20.
Oxygen debt is…
the amount of O2 required after exercise to fully breakdown the lactic acid produced.
Why is rice adapted for a high level of anaerobic respiration?
-roots are immersed in a low oxygen environment, so most of the respiration is anaerobic
Adaptations of rice:
- root cells are resistant to high doses of ethanol
- the stem contains aerenchyma to bring more O2 to the roots
Aerenchyma is…
made of loosely packed cells forming tissue in the stem, allowing CO2 to diffuse into the roots.
RQ is equal to one if…
carbohydrates are used as respiratory substrate and the respiration is aerobic
RQ is less than 1 if…
the respiratory substrate is either fat or protein and the respiration is aerobic. (fats = 0.7 and proteins = 0.9)
RQ is 0 when…
succulents do not evolve CO2 at the night as the same amount is used in carbon fixation.
Succulents also change…
carbohydrates to organic acids which utilise the oxygen but do not evolve carbon dioxide.
RQ(aerobic) is more than 1 if…
organic acids are broken down as respiratory substrates under aerobic conditions
RQ(anaerobic) is more than 1 if…
Anaerobic respiration takes place, so there is no consumption of O2. CO2 is produced in most cases, so the RQ is infinity. Carbohydrates are usual substrates.
Importance of RQ:
- determines the respiratory substrate
- shows the type of respiration being performed
- provides information about major transformation of food materials
Why is ATP useful source of energy?
- small so releases energy in suitable amounts, so easily manageable
- easily broken down, releasing energy rapidly
