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BIOL UNIT 3 mrs thomas > Respiration > Flashcards

Flashcards in Respiration Deck (26)
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Name 3 cellular activities that require ATP energy

Muscle contraction
Protein synthesis
Active transport


Describe 3 advantages of ATP for its function

It is soluble and easily transported around the cell
An immediate source of energy as only one enzyme is needed to hydrolyse it
Releases energy in useable amounts that are matched closely to the energy required in coupled reaction


In aerobic respiration what are the ways in which ATP can be synthesised and describe them

Substrate level phos > where an enzyme transfers a phosphate group from a substrate directly to ADP with no involvement of the ETC

Oxidative Phos where glucose is oxidised in a series of redox reactions that provide the energy to synthesise ATP. Oxygen must be present as the TEA


Explain how ADP is involved in making energy available for cells

ADP combined with Pi( an inorganic phosphate) to produce ATP, this reaction is catalysed by the enzyme ATPsynthetase. In order for ATP to release energy the terminal phosphate group is hydrolysed releasing 30.6KJmol-1 of energy. This reaction is catalysed by the enzyme ATPase


What is the terminal electron acceptor in aerobic respiration



Draw and label a mitochondria



What is the origin of the electrons that are passed alone the electron transport chain

Hydrogen atoms, which split to form H+ and E-


Why is SLP referred to as the simplest and oldest way to make ATP

Has no involvement of the ETC, no oxygen is needed and needs no pumps or carriers


Why does the diameter of the mitochondria not exceed 10 um

Because the diffusion pathway for O2 and CO2 must be as short as possible to be efficient


Why does the concentration of oxygen fall sometimes

Because oxygen is the terminal electron acceptor, it combines with H+ and E- to form water so the concentration of pure oxygen falls


What is produced in glycolysis

4 ATP and NADH2


How is reduced NAD used in aerobic respiration

Supplies high energy electrons to the ETC and protons to the proton pumps in the ETC


How is reduced NAD used in anaerobic respiration

Reduces pyruvate to lactic acid


Where does the Krebs cycle occur and why here

In the mitochondrial matrix because the enzyme required for the Krebs cycle are located here


Explain the process of Krebs cycle

Acetyl CoA enter the cycle and combines with a 4C acid to form a 6C compound
The 6C acid is dehydrogenated, making NADH2 to regenerate the 4C acid
(ATP is also made here by SLP)
The 4C acid can combine with more acetyl coA and the cycle is repeated


Why is it important that the 4C acid is regenerated in the Krebs cycle

In order for it to combine with Acetyl coA, to prevent it from accumulating


Explain why the overal count of ATP is not always 38

ATP is used to move pyruvate, ADP NADH2and FADH2 across the mitochondrial membrane
The proton gradient may be compromised by proton leakage across the inner mitochondrial membrane rather than passing through ATP synthetase
Molecules may also leak through the membrane preventing ATP from being generated


Where is the ETC located

On the cristae of the inner mitochondrial membrane


Name the molecules that show net movement into the mitochondrion



Name the molecules that sow net movement out of the the mitochondria



Explain why anaerobic respiration yields less ATP than aerobic

Anaerobic is the incomplete breakdown of glucose only producing 2 molecules of ATP per glucose molecule as energy still remains in lactate and ethanol, and oxygen does not act as the terminal electron acceptor


Describe the process of anaerobic respiration in animal cells

Pyruvate becomes the terminal electron acceptor, where it is reduced and accepts the H+ from NADH2 and is converted into lactate


State the way in which anaerobic respiration in a yeast cell differs from that in the animal cell

In yeast cells ethanol and carbon dioxide are produced in animals lactate is produced


Which part of aerobic respiration can lead to greater ATP production

Krebs cycle


Give a reason why ATP is used in the process of glycolysis

ATP activates glucose to convert into hexose biphosphate by accepting the Pi from the ATP


What provides the electrons in respiration