Metabolism, Cell Respiration and Photosynthesis

Question 1

Contrast metabolic chain reaction pathways with cyclical reaction pathways

Question 2

Define “activation energy”

Question 3

Explain the role of enzymes in lowering the activation energy of a reaction

Question 4

Contrast competitive and noncompetitive enzyme inhibition

Question 4

Define “enzyme inhibitor”

Question 5

Outline one example of a competitive enzyme inhibitor and one example of a noncompetitive enzyme inhibitor

Question 6

Describe allosteric regulation of enzyme activity

Question 7

Outline the mechanism and benefit of end-product inhibition

Question 8

Illustrate end-product inhibition of the threonine to isoleucine metabolic pathway

Question 9

State the consequence of an increase in isoleucine concentration

Question 10

Outline the reasons for development of new anti-malarial drugs

Question 11

Explain the use of databases in identification of potential new anti-malarial drugs

Question 12

Explain why the rate of reaction with increasing substrate concentration is lower with a non-competitive inhibitor compared to a competitive inhibitor

Question 13

State two methods for determining the rate of enzyme controlled reactions

Question 14

State the unit for enzyme reaction rate

Question 15

Given data, calculate and graph the rate of an enzyme catalyzed reaction

Question 16

Outline the use and benefits of the bioinformatics technique of chemogenomics in development of new pharmaceutical drugs

Question 17

Outline oxidation and reduction reactions in terms of movement of electrons, hydrogen or oxygen atoms

Question 18

Define “electron carrier”

Question 19

State the name of the electron carrier molecule used in cellular respiration

Question 20

Define “phosphorylation”

Question 21

State the consequence of a molecule being phosphorylated

Question 21

State the formula for the glycolysis reaction

Question 22

Outline the glycolysis reaction, including phosphorylation, lysis and energy harvest

Question 23

State that glycolysis occurs in both anaerobic and aerobic respiration

Question 24

State that glycolysis is an example of a metabolic pathway

Question 25

Define “decarboxylation” and “oxidation”

Question 26

​Summarize the reactant and products of the link reaction

Question 27

State that NADH and FADH2 are electron carriers formed during the Krebs cycle

Question 28

Outline the events of the Krebs cycle, referencing the formation of NADH and FADH2, formation of ATP and decarboxylation of acetyl groups

Question 29

State that NAD+ is reduced to become NADH in the link reaction and Krebs cycle

Question 30

State that FAD is reduced to become FADH2 in the Krebs cycle

Question 31

State that NADH and FADH2 carry electrons to the electron transport chain on the mitochondrial inner membrane

Question 32

State that at the electron transport chain, FADH2 and NADH given electrons to electron carrier proteins

Question 33

State that the movement of electrons through electron carrier proteins in the electron transport chain is used to pump protons (H+) across the inner mitochondrial membrane into the intermembrane space

Question 34

Define “oxidative phosphorylation” and “chemiosmosis”

Question 35

State that that formation of water in the matrix at the end of the electron transport chain helps to maintain the hydrogen gradient between the intermembrane space and the matrix

Question 35

​State that oxygen is the final electron acceptor in aerobic cellular respiration

Question 36

Outline how mitochondria structure could evolve through natural selection

Question 37

State evidence that suggests mitochondria were once free living prokaryotes

Question 38

State that electron tomography enables scientists to view the dynamic nature of mitochondrial membranes

Question 39

State that decarboxylation of glucose occurs in the linking reaction and Krebs cycle of aerobic respiration

Question 40

​Draw and label a diagram of the mitochondria

Question 41

State the function of the following mitochondrial structures: outer membrane, inner membrane, cristae, intermembrane space, matrix, ribosome and mtDNA

Question 42

State that Peter Mitchell’s proposal of the chemiosmotic hypothesis in 1961 lead to a major shift in our understanding of cellular processes

Question 43

State the location of the light dependent reactions of photosynthesis

Question 44

State that the light dependent reactions of photosynthesis include:
- Photoactivation
- Photolysis
- Electron transport
- Chemiosmosis
- ATP synthesis
- Reduction of NADP to NADPH + H+

Answer 44

Photoactivation:

Photolysis:

Electron transport:

Chemiosmosis:

ATP synthesis:

Reduction of NADP to NADPH + H+:

Question 45

State that the light dependent reactions convert light energy into chemical energy in the form of ATP and NADH

Question 46

State the location of the light independent reactions of photosynthesis

Question 47

Define “photosystem” and “reaction center”

Question 47

State that the light independent reactions of photosynthesis include:
- Carbon fixation
- Carboxylation of RuBP
- Production of triophosphate
- ATP and NADPH as energy sources
- ATP used to regenerate RuBP
- ATP used to produce carbohydrates

Answer 47

Carbon fixation:

Carboxylation of RuBP:

Production of triophosphate:

ATP and NADPH as energy sources:

ATP used to regenerate RuBP:

ATP used to produce carbohydrates:

Question 48

State that the light dependent reactions of photosynthesis begin at Photosystem II

Question 49

State that to replace the electrons lost during photoactivation, the reaction center chlorophyll takes electrons by splitting water

Question 49

Outline process of photoactivation of the reaction center chlorophyll

Question 50

State that in photoactivation at Photosystem II, the reaction center chlorophyll is oxidized and the plastoquinone (Pq) is reduced

Question 51

Draw a cross section of the thylakoid membrane to show the path of transfer of excited electrons, inclusive of Photosystem II, ATP synthase, an electron transport chain (with Pq first) and Photosystem II

Question 52

State that electrons pass from plastoquinone (Pq) through a chain of electron carrier molecules

Question 53

State that the energy released by the movement of electrons is used to pump protons across the thylakoid membrane, from the stroma into the thylakoid lumen

Question 54

State that the result of the electron transport chain is a proton gradient, with a high concentration of protons in the thylakoid lumen

Question 55

State that NADPH is an electron carrier molecule

Question 55

State that in chemiosmosis, ATP is generated as protons move down their concentration gradient through ATP synthase

Question 56

State that photoactivation of the reaction center chlorophyll in photosystem I excites electrons which pass through a different electron transport chain

Question 57

State that the electrons of Photosystem I are used to reduce NADP+ to form NADPH

Question 58

State that the electrons from the Photosystem II electron transport chain are used to replace the electrons lost during photoactivation of Photosystem I

Question 59

Define “carbon fixation” and “carboxylation”

Question 60

State that carbon fixation occurs in the chloroplast stroma

Question 60

State that the 5-carbon molecule ribulose bisphosphate (RuBP) is carboxylated by CO2, forming 2 3-carbon molecules called glycerate-3-phosphate (G3P)

Question 61

State that the enzyme that catalyzes the carboxylation of RuBP is called ribulose bisphosphate carboxylase (rubisco)

Question 62

State that ATP (from the light dependent reaction) provides the energy for NADPH (from the light dependent reaction) to reduce G3P, forming a three carbon carbohydrate, triose phosphate

Question 63

State that six turns of the Calvin Cycle are needs to produce one molecule of glucose

Question 64

State that in the Calvin Cycle, triose phosphate is used to regenerate RuBP and create glucose

Question 65

State that ATP is used to regenerate RuBP from triose phosphate

Question 66

Outline how chloroplast structure could evolve through natural selection

Question 67

State evidence that suggests chloroplast were once free living prokaryotes

Question 68

Outline Calvin’s “lollipop” experiment, including the role of:
- Radioactive carbon-14
- Green algae
- Air with CO2
- Light
- Varying the time of light exposure
- Heated alcohol
- Chromatography
- Autoradiography

Question 69

Draw and label a diagram of the chloroplast

Question 70

State the function of the following chloroplast structures: double membrane, thylakoids, pigment molecules, thylakoid lumen, and stroma

Question 71

State that the discovery of the radioactive 14C isotope allowed Calvin to determine the pathway of the light independent reactions of photosynthesis