Nutritional Biochemistry

Question 1

What are the two types of carbohydrate transporters?

Answer 1

SGLT1 – absorbs glucose and galactose

GLUT5 – transports fructose

Question 2

What are some vitamins involved in the pathway that takes pyruvate to acetyl-CoA?

Answer 2

TPP - Thiamine Pyrophosphate
FAD - Flavin Adenine Dinucleotide (Riboflavin)
NAD - Nicotinamide Adenine Dinucleotide (Niacin)

Question 3

• Cofactor for pyruvate dehydrogenase–decarboxylation
• Cofactor in pentose phosphate pathway–NADPH
• Maintains neural membranes and normal nerve conductions–pH, myelin, neurotransmitters

Answer 3

Thiamine/Vitamin B1

Question 4

Deficiency of Thiamine

Answer 4

Polyneuropathy – Dry Beriberi
Dilated cardiomyopathy – Wet Beriberi
Wernicke-Korsakoff syndrome

Question 5

• Coenzyme A–Amino acid, carbo, fat and nucleic acid metabolism
• Acyl carrier protein–fatty acid synthesis

Answer 5

Pantothenic acid/Vitamin B5

Question 6

Deficiency of pantothenic acid/vit B5

Answer 6

Dermatitis
Enteritis
Alopecia
Adrenal insufficiency

Question 7

Active forms of Riboflavin/Vitamin B2

Answer 7

Flavin mononucleotide (FMN)
Flavin adenine dinucleotide (FAD)

Question 8

Acts as an electron carrier for complex dehydrogenases and for the citric acid cycle to electron transport chain

Answer 8

Riboflavin/Vitamin B2

Question 9

Deficiency of Riboflavin/Vitamin B2

Answer 9

Cheilosis (scaling and fissures at the corner of the mouth)
Dermatitis
Corneal neovascularization

Question 10

What are some sources of niacin/vitamin B3?

Answer 10

Diet

Synthesized from tryptophan

Question 11

Active forms of Niacin?

Answer 11

NAD+: carbohydrate, fat, amino acids and nucleic acid degradation, citric acid cycle
NADH: citric acid cycle –> electron transport chain
NADP+: Glucose-6-phosphate dehydrogenase in the pentose phosphate shunt
NADPH: Used in synthesis of carbohydrates, fats, amino acids and nucleic acids

Question 12

Deficiency in Niacin/Vitamin B3?

Answer 12

Glossitis

Pellagra

Question 13

Active forms of Biotin/Vitamin B7?

Answer 13

Biotin bound to carboxylases
Released by biotinidase in small intestine
Bound in cells to carboxylases

Question 14

Carboxylase cofactor–binds CO2
For pyrovate carboxylase
Acetyl CoA carboxylase

Answer 14

Biotin/Vitamin B7

Question 15

Deficiency of biotin/vitamin B7

Answer 15

Dermatitis
Hair loss (alopecia)
Enteritis

Question 16

Active form of pyridoxine/Vitamin B6

Answer 16

Pyridoxal phosphate

Question 17

Coenzyme involved in amino acid degradation/conversion to other important molecules
-Aminotransferases
-Decarboxylases–serotonin, norepi
-Serin hydroxymethyltransferase – one carbon metabolism/myelination
-Aldolases
Coenzyme involved in glycogen degradation
-Glycogen phosphorylase
Coenzyme involved in porphyrin synthesis

Answer 17

Pyridoxin/Vitamin B6

Question 18

Deficiency in Pyridoxin/Vitamin B6

Answer 18

Convulsions
Dermatitis
Peripheral neuropathy
Sideroblastic anemia

Question 19

Active form of Folate/Vitamin B9

Answer 19

Tetrahydrofolate

Question 20

Carrier of 1 carbon units for purine synthesis, dTMP synthesis from dUMP and conversion of homocysteine to methionine for S-adenosylmethionine synthesis

Answer 20

Folate/Vitamin B9

Question 21

Deficiency of Folate/Vitamin B9

Answer 21

Megaloblastic anemia

Fetal neural tube defects

Question 22

How is Cobalamin/Vitamin B12 absorbed?

Answer 22

Through an Intrinsic factor – Vitamin B12 complex

Question 23

Cofactor for methionine synthase and methylmalonyl-CoA mutase
Required fro TH4 Folate availability for DNA synthesis
Functions in myelin synthesis

Answer 23

Cobalamin/Vitamin B12

Question 24

Deficiency of Cobalamin/Vitamin B12

Answer 24

Megaloblastic anemia
Fetal neural tube defects
Demyelination
Neural degeneration

Question 25

Where are most B-vitamins absorbed?

Answer 25

Duodenum | Jejunum

Question 26

Where is B12 absorbed?

Answer 26

Ileum

Question 27

Where is microbiota produced biotin absorbed?

Answer 27

Large intestine

Question 28

Active form of Ascorbate/Viatmin C

Answer 28

Ascorbic acid

Question 29

Antioxidant Cofactor of enzymes that reduce metal ions Post-translational modification of proteins--collagen Synthesis of ntm and hormones

Answer 29

Ascorbate/Vitamin C

Question 30

Deficiency of Vitamin C

Answer 30

Abnormal collagen cross linking leading to bleeding | Scurvy

Question 31

Where is vitamin E/tocopherol stored?

Answer 31

In adipose tissue, liver, muscle

Question 32

Antioxidant-scavenges free radicals | Recycled by Vitamin C

Answer 32

Vitamin E/Tocopherol

Question 33

Deficiency of Vitamin E/Tocopherol?

Answer 33

Hemolytic anemia Muscle weakness Demyelination

Question 34

Cofactor for coagulation factors 2, 7, 9, 10, protein C and protein S; also for bone calcium binding proteins Modified Gla residue binds calcium, localizes to activated platelets

Answer 34

Vitamin K/Phylloquinone

Question 35

Deficiency of vitamin K/phylloquinone?

Answer 35

Bleeding

Question 36

Where is vitamin A stored?

Answer 36

Liver

Question 37

Active forms of vitamin A and what they are used for

Answer 37

Beta-carotene: antioxidant, vit A precursor Retinol (vit a): major transport form 11-cis retinal (retinaldyhyde): vision Retinoid acid: gene regulation

Question 38

What are some things that retinoid acid regulates the gene expression of?

Answer 38

``` Epithelial cell function Mucous cell function Immunity Reproduction Development ```

Question 39

Deficiency of Vitamin A (carotenes, retinoids)

Answer 39

``` Night blindness Susceptibility to infection Dry scaly skin Corneal degeneration Alopecia Oseoporosis ```

Question 40

What does 11-cis-retinal bind?

Answer 40

Rhodopsin in rods | Cone pigments in cones

Question 41

Forms of vitamin D/Calciferols

Answer 41

Dietary in micelles: Cholecalciferol (animals), ergocalciferol (plants) Hormone: 7-dehydrocholesterol --> vitamin D2 Active: 1, 25 dihydroxyvitamin D

Question 42

Controls expression genes that act in calcium and phosphate absorption in the intestine, bone formation and dissolution, renal retention of calcium and phosphate Also: cell cycle arrest, apoptosis, immune suppression, anti-inflammation, differentiation Requires retinoic acid

Answer 42

Vitamin D/Calciferols

Question 43

Deficiency of vitamin D/calciferols

Answer 43

Children-rickets | Adults-osteomalacia

Question 44

Where are fat soluble vitamins absorbed?

Answer 44

Duodenum/jejunum: all fat soluble vitamins Ileum: vitamin D Large intestine: microbiota produced vitamin K

Question 45

Where are minerals absorbed?

Answer 45

Stomach and the entire intestine

Question 46

Mineral involved in oxygen transport and energy metabolism

Answer 46

Iron

Question 47

Mineral involved in wound healing and spermatogenesis

Answer 47

Zinc

Question 48

Mineral involved in thyroid hormones

Answer 48

Iodine

Question 49

Mineral with antioxidant properties, involved in electron transport, collagen-crosslinking, development

Answer 49

Copper

Question 50

Mineral involved in dental health

Answer 50

Fluoride

Question 51

Mineral with antioxidant properties and involve in thyroid hormone function

Answer 51

Selenium