3 Enzymes, Vitamins & Minerals

Question 1

What are the fat soluble vitamins?

Answer 1

A D E K

Question 2

Fat malabsorption may lead to deficiencies in which vitamins?

Answer 2

A D E K

Question 3

Which vitamin group is known as Retinoids?

Answer 3

Vitamin A

Question 4

Vitamin A is involved in which function of the body?

Answer 4

Vision

Question 5

What is the common precursor of A Group Vitamins?

Answer 5

ß-Carotene

Question 6

Decreased synthesis of Cholecalciferol is a result of what?

Answer 6

Inadequate sunlight exposure

Question 7

Cholecalciferol is a cholesterol derivative known as which vitamin?

Answer 7

D₃

Question 8

Rickets and Osteomalacia are a result of a deficiency of which vitamin group?

Answer 8

Vitamin D

Question 9

Primary Hypoparathyroidism is caused by a deficiency of which vitamin group?

Answer 9

Vitamin D

Question 10

Anorexia, polyuria, Renal Calculi and hypercalcaemia may be indicative of a toxic excess of which vitamin?

Answer 10

Vitamin D

Question 11

Regulation of bone mineralisation is associated with the levels of which vitamin?

Answer 11

Vitamin D

Question 12

Bile salts are important in the intestinal absorption of which vitamin group?

Answer 12

Vitamin E

Question 13

Which fat-soluble vitamin interacts with reactive oxygen species in order to protect the body?

Answer 13

Vitamin E

Question 14

Vitamin E is converted to a Quinone Intermediate in a process which serves what function in the body?

Answer 14

Removal of Free Radicals

Question 15

Vitamin E, colloquially, is considered to have what property?

Answer 15

Antioxidant Proerties

Question 16

Abetaproteinaemia can cause deficiencies in which vitamin group?

Answer 16

Vitamin E

Question 17

Vitamin K is critical for post translational modification of what proteins?

Answer 17

Coagulation factors

(II, VII, IX, X)

Question 18

Use of broad-spectrum antibiotics can destroy synthesis of what vitamin?

Answer 18

Vitamin K

Question 19

Why are newborn babies administered vitamin K at birth?

Answer 19

They lack bowel colonisation

requird for production of vitamin K

Question 20

Warfarin, a Dicoumarin drug inhibits the action of which vitamin in order to reduce thrombogenesis?

Answer 20

Vitamin K

Question 21

Which form of Vitamin A is essential in Embryonic Development?

Answer 21

Retinoic Acid

Question 22

What is the metabolic role of the vitamin group known as Tocopherols?

Answer 22

Reactive Oxygen Species scavenging

Vitamin E

Question 23

How can you have an overdose of a fat soluble vitamin rather than a water soluble one?

Answer 23

fat soluble vitamins are retained and cannot be directly excreted

Question 24

The body has no storage capacity for water soluble vitamins whith the exception of:

Answer 24

B₁₂

Question 25

Which B Group vitamin is known as Thiamine?

Answer 25

B₁

Question 26

Thiamine is involved in the decarboxylation of which molecule?

Answer 26

Pyruvate

Question 27

Enzymic conversion of **Pyruvate ⇔ Acetyl CoA** is assisted by which vitamin?

Answer 27

Thiamine B₁

Question 28

deficiency of Vitamin B₁ causes wich disease?

Answer 28

Beriberi

Question 29

Vitamin B₂ is also known as:

Answer 29

Riboflavin

Question 30

**Riboflavin**, Vitamin B₂ is important in the synhthesis of which electron transporting molecule?

Answer 30

FAD⁺

Question 31

Maize, when untreated, results in a protein low in which molecule? ## Footnote *Associated with Niacin*

Answer 31

Tryptophan

Question 32

Deficiency of vitamin B₃ results in which condition?

Answer 32

Pellagra

Question 33

Vitamin B₃ is also known as:

Answer 33

Niacin

Question 34

Formation of NADH requires what vitamin?

Answer 34

Niacin B₃

Question 35

Vitamin B₅ is also known as:

Answer 35

Pantothenic Acid

Question 36

Acetyl CoA contains a B-group vitamin by what name?

Answer 36

Pantothenic Acid B₅

Question 37

Amino acid metabolism relies on good levels of which vitamin?

Answer 37

Pyridoxine B₆

Question 38

Vitamin B₆ is also known as:

Answer 38

Pyridoxine

Question 39

Which B-Vitamin is synthesised solely by bacteria?

Answer 39

Cobalamin B₁₂

Question 40

**Pernicious Anaemia** is a result of deficiency of which vitamin?

Answer 40

B₁₂ Cobalamin

Question 41

Secretion of intrinsic factor by the parietal cells of the stomach is important for the function of which vitamin?

Answer 41

Cobalamin B₁₂

Question 42

Deficiency of vitamin B₁₂ results in inhibited production of which critical amino acid?

Answer 42

Methionine

Question 43

Vitamin B₇ is known as:

Answer 43

Biotin

Question 44

What are the metabolic functions of **vitamin B₇** (Biotin)?

Answer 44

Gluconeogenesis Lipogenesis Catabolism of BCAA

Question 45

Vitamin B₉ is also known as:

Answer 45

Folic Acid

Question 46

What is the function of **vitamin B**₉ (Folic Acid)?

Answer 46

DNA synthesis

Question 47

Deficiency of **vitamins K** and **C** cause easy bruising and bleeding, however which one has **associated connective tissue problems**?

Answer 47

Vitamin C

Question 48

Vitamins C and K both affect bleeding, however deficiency of which vitamin will increase clotting time?

Answer 48

Vitamin K

Question 49

What are Enzymes?

Answer 49

Biological Catalysts made from Proteins

Question 50

Can an enzyme force a reaction that is not spontaneous?

Answer 50

no

Question 51

What is the effect of an Enzyme on **Activation energy**?

Answer 51

Decrease

Question 52

Thermodynamically spontaneous reactions are Endergonic or Exergonic?

Answer 52

Exergonic

Question 53

In an **Endergonic** reaction, the change in **Gibbs Free Energy** ΔG, is less than, or greater than zero?

Answer 53

Greater than zero ## Footnote *Positive*

Question 54

In an **Exergonic** reaction, the change in **Gibbs Free Energy** ΔG, is less than, or greater than zero?

Answer 54

Less than zero ## Footnote *Negative*

Question 55

What effect do **enzymes** have on the change in **Gibbs Free Energy,** ΔG, when a reaction is completed?

Answer 55

No effect

Question 56

What is the function of **Oxidoreductase** enzymes?

Answer 56

Transfer of electrons from donors to acceptors

Question 57

What class of enzymes is responsible for the transfer of electrons from donors to acceptor molecules?

Answer 57

Oxidoreductases

Question 58

What is the function of **transferase** enzymes?

Answer 58

Transfer of functional groups between molecules

Question 59

What enzyme class is involved with the transfer of functional groups between molecules?

Answer 59

Transferases

Question 60

What is the function of **Hydrolase** class enzymes?

Answer 60

Cleavage of bonds by addition of water

Question 61

Which enzyme class is involved with the cleavage of bonds using water?

Answer 61

Hydrolases

Question 62

What is the function of **Lyase** class enzymes?

Answer 62

Addition of H₂O, CO₂ and NH₃ to double bonds (Or removing them to create double bonds)

Question 63

Which enzyme class is responsible for either the addition of water, ammonia or carbon dioxide to double bonds, or the removal of the same in order to create double bonds?

Answer 63

Lyases

Question 64

What is the function of **Isomerase** class enzymes?

Answer 64

conversion of a molecule to isomeric forms ## Footnote *Creation of isomers*

Question 65

What class of enzymes is responsible for the creation of various isomeric forms of the same molecule?

Answer 65

Isomerase

Question 66

What is the function of **Ligase** class enzymes? (also known as Synthetases)

Answer 66

Forming new covalent bonds using ATP

Question 67

Which class of enzyme uses ATP to form new covalent bonds?

Answer 67

Ligase

Question 68

Ligase class enzymes are sometimes known as:

Answer 68

Synthetases

Question 69

Which **metal** is required in the **Pyruvate Dehydrogenase complex**?

Answer 69

Mg

Question 70

A number of inorganic metal ions are used in biochemical reactions, are they **Cofactors**, or **Coenzymes**?

Answer 70

Cofactors

Question 71

Which equation describes the relationship between the velocity of a reaction, and the concentrations of both the substrate and enzyme?

Answer 71

Michaelis-Menten Equation

Question 72

Which constant defines the number of **substrate molecules** which convert to **product** *per* **enzyme molucule**, *per* unit time?

Answer 72

K_cat

Question 73

What does the Michaelis-Menten equation assume about the conversion of the **enzyme-substrate complex** ⇒ **product** + **Enzyme**?

Answer 73

This is a rate limiting step

Question 74

In terms of enzymatic activity, what does **V_max** signify?

Answer 74

When all enzymes are saturated with substrate ## Footnote *The reaction reaches a maximum velocity*

Question 75

What is the property that describes how easily and readily an enzyme will bind to a substrate?

Answer 75

Affinity

Question 76

Enzymes with a low **K_m** will have a higher *or* lower **affinity** for a substrate?

Answer 76

Higher

Question 77

Enzymes with a high **K_m** will have a higher *or* lower **affinity** for a substrate?

Answer 77

Lower Affinity

Question 78

How is the **K_m** affected by enzymes with a **low** **affinity**?

Answer 78

K_m is high

Question 79

How is the **K_m** affected by enzymes with a **high affinity**?

Answer 79

**K**_m is low

Question 80

What aspect of chemical concentrations is relevant when considering the **K_m** with respect to **V_max** for an enzyme?

Answer 80

whether V_max occurs in biologically relevant conditions

Question 81

In an enzymatic reaction, **biologically relevant conditions** are evaluated relative to the relationship of **which two factors**?

Answer 81

K_m and V_max

Question 82

In **Enzymatic Reactions**, what is the fixed relationship between **V_max** and **K_m**?

Answer 82

**K_m** corresponds to half of **V_max**

Question 83

Glucokinase is much more sensetive to glucose concentration than hexokinase, which enzyme has the **higher K_m**?

Answer 83

Glucokinase

Question 84

A **rapid acting** scavenger enzyme with a rate relatively insensetive to substrate concentration will have a high *or* low **K_m** relative to its regulatory counterpart?

Answer 84

Low K_m

Question 85

What are the three forms of enzyme inhibition?

Answer 85

Competetive Non-Competetive Un-Competetive

Question 86

In addition to substrate concentration, which two physical properties can affect enzyme performance, with respect to V?

Answer 86

Temperature pH

Question 87

An enzyme will respond with an increase or decrease in activity to varying degrees dependant on the effector molecule - what is this called?

Answer 87

Allosterism

Question 88

Ethanol is given in the treatment of **acute methanol poisoning**, because of the relatiohsip between the liver enzyme **Alcohol Dehydrogenase** and the two chemicals - why?

Answer 88

Ethanol has a lower K_m than Methanol ## Footnote *Competes for the enzymes to avoid the poisonous byproduct, Formic Acid*

Question 89

Describe the effects on **K_m** and **V_max **in **competetive** enzyme inhibition:

Answer 89

K_m - Increased V_max - Unchanged

Question 90

Describe the effects on **K_m** and **V_max** in **uncompetetive** enzyme inhibition:

Answer 90

K_m - Reduced V_max - Reduced

Question 91

Describe the effects on **K_m** and **V_max** in **Noncompetetive** inhibition:

Answer 91

K_m - Unchanged V_max - Reduced

Question 92

What is the purpose of the **Pyruvate dehydrogenase complex**?

Answer 92

Linking Glycolysis to the TCA cycle

Question 93

Which set of enzymatic reactions links **Glycolysis** to the **TCA cycle**?

Answer 93

Pyruvate Dehydrogenase Complex