Topic 2.8: Cellular Respiration Flashcards Preview

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Flashcards in Topic 2.8: Cellular Respiration Deck (24)
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Definition of cell respiration

Controlled release of energy from organic compounds in cells to form ATP


Types of cellular respiration

a) Anaerobic
b) Aerobic


Anaerobic cellular respiration

Partial breakdown of glucose in the cytosol for a small yield of ATP


Aerobic cellular respiration

Use of O2 to completely break down glucose in the mitochondria for a large yield of ATP


Definition of ATP

High energy molecule that works as an immediate source of energy for cell processes


Activities which require energy

a) Biosynthesis of macromolecules
b) Active transport
c) Nerve transmission
d) Growth and reproduction
e) Movement


Reaction of ADP and P to form ATP

a) When ATP is hydrolyzed, the energy stored in its phosphate bond is released to be used by the cell
b) Cell respiration uses energy stored in organic molecules to regenerate ATP from ADP + Pi


When does anaerobic respiration occur?

a) A short but rapid burst of ATP is needed
b) O2 supplies run out in cells


Products of anaerobic respiration in:
a) Animals
b) Plants / Yeast

a) Lactate
b) Ethanol / CO2


Steps in aerobic respiration

a) Glycolysis
b) Fermentation


What happens in glycolysis?

a) Breakdown of glucose into two molecules of pyruvate
b) Production of two molecules of ATP and NADH


What happens in fermentation?

a) Restoration of NAD+ by oxidation of NADH
b) Production of lactate / ethanol + CO2 from the reduction of pyruvate.


What organic molecules are consumed in anaerobic respiration?

Only carbohydrates can be consumed


Applications of Anaerobic Respiration

a) Muscle contraction
b) Food processing


Muscle contraction

a) When exercising at high intensity, the cells’ energy demands exceed what the available O2 can supply aerobically
b) Cells will break down glucose anaerobically to maximize ATP production
c) Production of lactic acid increases and leads to muscle fatigue
d) When the individual stops exercising, O2 levels increase and lactate is converted into pyruvate


Food processing

a) CO2 produced cannot escape from the dough and forms bubbles causing the dough to rise
b) Bioethanol is produced from sugar cane and maize, using yeast
c) Production of lactic acid modifies milk proteins to generate yogurts and cheeses


When does aerobic respiration occur?

Presence of O2


Outline of the stages in aerobic respiration

a) Glycolysis
b) Link reaction
c) Krebs cycle
d) Electron Transport Chain


Products of aerobic respiration

C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy (ATP)


Anaerobic vs Aerobic respiration
a) Reactants
b) Combustion
c) Energy field
d) Products
e) Location
f) Stages

a) Glucose | Glucose + CO2
b) Incomplete | Complete
c) Low | High
d) Lactate / CO2 + Ethanol | H2O + C2O
e) Cytoplasm | Cytoplasm + Mitochondrion
f) Glycolysis, fermentation | Glycolysis, link reaction, Krebs cycle, ETC


Definition of respirometer

Device that determines an organism's respiration rate by measuring consumption of oxygen


Components of a respirometer

a) Respiring organism
b) Filter paper wicks
c) KOH solution
d) U-tube manometer
e) Syringe
f) Metal cage
g) Tube A


Factors that influence respiration

a) Temperature
b) Light (Plants)
c) Age


How is oxygen consumption measured in a respirometer?

a) When an alkali is included to absorb CO2, oxygen consumption can be measured as a change in pressure within a system using a U-tube manometer.
b) A decrease in oxygen levels indicates an increase in respiration