Topic 2.8: Cellular Respiration Flashcards
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
