Key Knowledge 5 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

cellular respiration 

A

the process by which cells create usable energy in the form of ATP from a series of biochemical reactions, involving the breakdown of glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

cellular respiration equation

A

glucose + oxygen —> carbon dioxide + water + energy

C6H12O6 + 6 O2 —> 6 CO2 + 6 H2O + 36 or 38 ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Animals: lactic acid fermentation

A

Glucose —> Lactic acid + ATP

C6H12O6 2 C3H6O3 2 ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Plants and yeast: alcohol fermentation

A

Glucose —> Ethanol + Carbon dioxide + ATP

C6H12O6 C2H5 H 2 CO2 2 ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

glycolysis 

A

the first stage of aerobic cellular respiration in which glucose is converted to two pyruvate molecules. location is in the cytosol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Krebs cycle 

A

the second stage of aerobic cellular respiration, where multiple reactions occur to create ATP, NADH, FADH2, and the waste product CO2. Also known as the citric acid cycle or TCA cycle. The location is in the mitochondrial matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

electron transport chain 

A

the third stage of aerobic cellular respiration, in which a series of protein complexes embedded in the inner membrane of a mitochondrion harness the stored energy in NADH and FADH2 to generate large amounts of ATP. The location is the cristae of the mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Mitochondria

A

crucial to aerobic cellular respiration as they are the site of the second and third stages, with the first stage (glycolysis) occurring in the cytosol of the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

glycolysis inputs

A
  • 1 glucose (C6H12O6)
  • 2 ADP + 2 Pi
  • 2 NAD+ + 2 H+
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

glycolysis outputs

A
  • 2 pyruvate
  • 2 ATP
  • 2 NADH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

krebs cycle inputs

A
  • 2 acetyl-CoA (derived from 2 pyruvate)
  • 2 ADP + 2 Pi
  • 6 NAD + 6 H+
  • 2 FAD + 4 H+
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Krebs cycle outputs

A
  • 4 carbon dioxide (CO2)
  • 2 ATP
  • 6 NADH
  • 2 FADH2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

overall results from krebs cycle

A
  • By breaking down acetyl-CoA, protons and high-energy electrons are released. These protons and electrons are loaded onto NAD+ and FAD molecules to generate high-energy coenzymes NADH and FADH2.
  • The Krebs cycle produces two CO2 molecules for every one acetyl-CoA molecule. When added to the single CO2 molecule produced from each of the two pyruvates undergoing the link reaction, this means a total of six CO2 molecules are produced for every original glucose molecule.
  • The Krebs cycle produces a small amount of energy in the form of two ATP (one per acetyl-CoA molecule).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

ETC inputs

A
  • 6 oxygen (O2) + 12 H+
  • 26 or 28 ADP + Pi
  • 10 NADH
  • 2 FADH2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

ETC outputs

A
  • 6 water (H2O)
  • 26 or 28 ATP
  • 10 NAD+ + 10 H+
  • 2 FAD + 4 H+
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

ETC steps

A
  1. NADH and FADH2 unload electrons and protons at the first and second protein complexes of the electron transport chain that reside in the inner mitochondrial membrane. The following reactions take place:
    (1) NADH —> NAD+ + H+ + 2 e–
    (2) FADH2 —> FAD + 2 H+ + 2 e–.
  2. The excited electrons (from NADH and FADH2) are transferred through a number of different protein complexes embedded in the electron transport chain, powering the active transport of protons (H+) from the mitochondrial matrix into the narrow intermembrane space.
  3. This leads to a build-up of protons in the intermembrane space.
  4. To move down their concentration gradient, these protons must travel through the specialised protein channel ATP synthase
  5. This process produces large amounts of ATP, but also leads to many free protons and electrons building up in the matrix.
17
Q

Enzymes and coenzymes in cellular respiration

A

The tightly controlled sequence of biochemical reactions in cellular respiration relies heavily on the use of enzymes and coenzymes to ensure they happen at a fast rate.

18
Q

unloaded coenzymes

A
  • ADP
  • NAD+
  • FAD
19
Q

loaded coenzymes

A
  • ATP
  • NADH
  • FADH2
20
Q

anaerobic fermentation 

A

a metabolic pathway that occurs in the absence of oxygen. Involves glycolysis, followed by further reactions that convert pyruvate into lactic acid in animals, or ethanol and CO2 in yeasts

21
Q

lactic acid fermentation

A

the process of anaerobic fermentation in animals, where pyruvate produced via glycolysis is converted to lactic acid

22
Q

ethanol fermentation 

A

the process of anaerobic fermentation in yeasts, where pyruvate produced via glycolysis is converted to ethanol and carbon dioxide. Also known as alcohol fermentation

23
Q

temperature and pH

A

Temperature and pH have a large effect on the rate at which cellular respiration occurs due to their effect on enzymes, which are essential in cellular respiration

24
Q

glucose

A

Increasing glucose availability increases the rate of cellular respiration until the enzymes reach the saturation point.

25
Q

oxygen

A

Increasing the concentration of oxygen will increase the rate of aerobic respiration.

26
Q

Enzyme inhibition 

A

Enzyme inhibitors decrease the rate of cellular respiration by reducing the activity of enzymes involved in the process.

27
Q

biofuel

A

Biofuels are made from organic material known as biomass, which is plant and animal material that can be sourced from many of our existing industries. They offer an alternative to traditional fossil fuels like coal and gas, which are non-renewable

28
Q

The process of creating bioethanol

A
  1. Deconstruction
  2. Digestion by enzymes
  3. Ethanol fermentation
  4. Purification and dehydration
29
Q

Deconstruction

A

a process that involves breaking down the cell wall and cellulose of wood, paper, plastic and other plant fibres.

30
Q

Digestion by enzymes

A

the break down the starch and cellulose and convert them into glucose and other sugars. This breaking down of polysaccharides is aided by the presence of water in a process known as hydrolysis.

31
Q

Ethanol fermentation

A

Ethanol diffuses out of the yeast cells and is harnessed for biofuel production. The ethanol is produced as a product of this process, rather than coming from within the plant.

32
Q

Purification and dehydration

A

The ethanol is distilled via the removal of water, converting it into a usable form called biofuel. The biofuel is then purified and is ready to be used as liquid fuel.