Cellular Respiration

Question 1

Define cellular respiration

Answer 1

Cellular respiration refers to the process by which cells create usable energy in the form of ATP from a series of biochemical reactions involving breakdown of glucose.

Question 2

Define aerobic cellular respiration

Answer 2

Aerobic cellular respiration refers to the metabolic pathway that occurs in the presence of oxygen, involves three stages, during which glucose and oxygen are converted to ATP, CO2 and water. Occurs at a slow pace

Question 3

Define anaerobic fermentation

Answer 3

anaerobic fermentation refers to the 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 carbon dioxide in yeasts. Occurs at a fast pace.

Question 4

Define Glycolysis

Answer 4

Glycolysis refers to the first stage in aerobic cellular respiration in which glucose is converted to two pyruvate molecules.

Question 5

Define the Krebs Cycle

Answer 5

The Kreb cycle refers to the second stage in aerobic cellular respiration where multiple reactions occur to create ATP, NADH, FADH2 and the waste product of carbon dioxide.

Question 6

Define the electron transport chain

Answer 6

the electron transport chain refers to the third stage in cellular respiration in which a series of protein complexes embedded in the inner membrane of a mitochondrian harness the stored energy in NADH and FADH2, to generate large amounts of ATP.

Question 7

Define cytosol

Answer 7

The cytosol refers to the aqueous fluid that surrounds a cell’s organelles inside the plasma membrane

Question 8

Define crista/cristae

Answer 8

The crista refers to the folds of the inner membrane of a mitochondrion. The site of the Kreb Cycle.

Question 9

Define pyruvate

Answer 9

Pyruvate refers to the three-carbon molecule that can be formed from the breakdown of glucose via glycolysis.

Question 10

Identify the inputs, outputs and location of Glycolysis

Answer 10

Inputs include: (c6h12o6), 2 ADP + 2Pi and 2 NAD+ + 2 H+. Outputs include: 2 pyruvate, 2 ATP and 2 NADH. It occurs in the cytosol.

Question 11

Define NAD

Answer 11

nicotinamide adenine dinucleotide refers to a coenzyme that acts as a proton (H+) and electron carrier in cellular respiration. NAD can cycle between its NAD+ and NADH forms, depending on the reaction its participates in.

Question 12

Define FAD

Answer 12

flavin adenine dinucleotide refers to the coenzyme that acts as a proton (H+) and electron carrier in cellular respiration. Can cycle between FAD and FADH2,, depending on the reaction it participates in.

Question 13

Define acetyl-CoA

Answer 13

acetyl-CoA refers to the product of the link reaction where pyruvate is combined to coenzyme A, creating the primary input into the Krebs cycle.

Question 14

Identify the inputs, outputs and location of Kreb Cycle

Answer 14

Inputs include: 2 acetyl-CoA (derived from 2 pyruvates), 2 ADP + 2 Pi, 6 NAD+ + 6 H+ and 2 FAD + 4 H+. Outputs include: 4 carbon dioxide, 2 ATP, 6 NADH and 2 FADH2. It occurs in the mitochondrial matrix.

Question 15

Identify the inputs, outputs and location of the Electron Transport Chain

Answer 15

Inputs include: 6 oxygen (O2) + 12 H+, 26 or 28 ADP + 26 or 28 Pi+, 10 NADH and 2 FADH2. Outputs include: 6 water molecules, 26 or 28 ATP, 10 NAD+ + 10 H+ and 2 FAD + 4 H+. It occurs in the cristae of the mitochondria.

Question 16

Define ATP synthase

Answer 16

ATP synthase refers to an enzyme in the inner mitochondrial membrane that uses the concentration gradient of H+ to synthesise ATP from ADP to Pi+.

Question 17

Identify the chemical equation of cellular respiration

Answer 17

the overall equation of cellular respiration is represented as: C6H12O6 + 6O2 > 6CO2 + 6 H2O + 30 or 32 ATP.

Question 18

Define the process of lactic acid fermentation

Answer 18

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

Question 19

Define the process of ethanol/alcohol fermentation

Answer 19

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

Question 20

List the factors affecting the rate of cellular respiration

Answer 20

factors affecting include: temperature and pH, glucose, oxygen and enzyme inhibition.

Question 21

Define fossil fuels

Answer 21

fossil fuels refers to fuel that formed over tens of millions of years from the remains of dead organic material. Considered non-renewable.

Question 22

Define biofuel

Answer 22

biofuels refer to fuel created from organic material known as biomass.

Question 23

Define biomass

Answer 23

biomass refers to an organic material, including plants, animals by-products and biological waste material. Multi-sourced from different industries.

Question 24

define carbon neutral

Answer 24

carbon neutral refers to a state in which there is no net release of carbon dioxide into the atmosphere, meaning there is a balance between amount of CO2 that is emitted during combustion of a fuel and how much was originally absorbed during the formation process of the fuel.

Question 25

Identify the steps in creating biofuels

Answer 25

the steps are Deconstruction, Digestion by enzymes, Ethanol fermentation and Purification and dehydration.

Question 26

Define first-generation biofuels

Answer 26

first-generation biofuels refer to biofuels produced from edible food crops such as corn or sugar cane. Compete directly with agricultural land. Easier to break down

Question 27

Define second-generation biofuels

Answer 27

second-generation biofuels refer to biofuels produced from non-edible crops such as agricultural and forestry residues and municipal waste. Compete less with agricultural land. Harder to break down.