Biochem- Vitamins and Iron

Question 1

Which 2 forms can B12 exist in the body as?

Answer 1

Free or bound

Question 2

What is the free B12 bound to?

Answer 2

Haptocorrins (transcobalamin I)

Question 3

Where does the Haptocorrins come from?

Answer 3

salivary and gastric mucosa

Question 4

What is the bound B12 bound to?

Answer 4

dietary proteins

Question 5

What causes the bound B12 to be released from the dietary proteins?

Answer 5

digestive proteases in the stomach and small intestine

Question 6

Once the B12 is bound to Haptocorrins, what are the steps to bind it to intrinsic factor?

Answer 6

The Haptocorrins get degraded by pancreatic proteases to allow it to bind to intrinsic factor

Question 7

What happens with the B12-IF complex?

Answer 7

it attaches to specific receptors in the ileum and is internalized

Question 8

Once the B12 is inside the cells of the GI, what does it bind to next?

Answer 8

transcobalmin II

Question 9

Once bound to transcobalmin II, where does the complex go?

Answer 9

into the circulation and then to the tissies.

Question 10

Which organ takes up 50% of the transcobalmin II-B12 complex and stores it for 3-6 years?

Answer 10

Liver

Question 11

What is the biggest problem in expectant mothers if they dont take folate?

Answer 11

Neural tube defects

Question 12

What is defective, biologically, which causes the neural tube defects from an inadequate folate intake?

Answer 12

DNA synthesis

Question 13

How else is folate used in the body to repair certain systems?

Answer 13

used for DNA repair

Question 14

How is folate used in DNA repair?

Answer 14

It does the methylization of dUMP to dTTP –> no folate –> uracil in DNA –> DNA repair cannot continue –> fragmented DNA

Question 15

What is the condition called when there are clumps of neutrophilic leukocytes in the bone marrow and peripheral blood of patients with improper folate or B12 intake?

Answer 15

Megaloblastic anemia

Question 16

What are the Sx to megaloblastic anemia?

Answer 16

fatigue, loss of appetite, pale skin, red/swollen tongue, and bleeding gums

Question 17

Why is vitamin A so important for your big, beautiful, sexy eyes?

Answer 17

It’s required for the synthesis of rhodopsin

Question 18

What are the Sx for inadequate vitamin A intake?

Answer 18

night blindness and xeropthalamia (severe drying of eye)

Question 19

Beri-beri is a deficiency in what vitamin?

Answer 19

B1 (thiamine)

Question 20

What are the general Sx of Beri-beri?

Answer 20

pitting edema, weight loss, emotional disturbance (OH GOD THE BERRIES), sensory problems and cardio problems

Question 21

This form of Beri-Beri is when the nervous system is affected by the low B1: ataxia, paresthesias, nystagmus, loss of muscle strength and tendon reflexes.

Answer 21

Dry beri-beri

“dry neurons”

Question 22

This form of beri-beri is in infants when the mothers were deficient in B1.

Answer 22

Infantile beriberi

Question 23

This form of beri-beri is when the cardio systems are affected: PITTING EDEMA, irregular heartbeat, increased HR

Answer 23

Wet beri-beri

“wet because of blood stuff and edema!”

Question 24

This B1 deficiency is in alcoholics, where there is an inability to absorb B1.

Answer 24

Wernicke-korsakoff syndrome

Question 25

What are the Sx of Wenicke's?

Answer 25

triad of ocular disturbances/nystagmus, mental state change, and ataxia

Question 26

What are the Sx of Korsakoff?

Answer 26

severe memory impairment lol wut.

Question 27

This vitamin is a coenzyme forms are NADH and NADPH and comes from meat, fish, cereals and enriched grains.

Answer 27

B3 (niacin)

Question 28

This disease is a deficiency in B3, and is characterized by dermatitis, diarrhea, dementia and death (4 D's).

Answer 28

Pallegra

Question 29

How is niacin used in large doses to treat hyperlipoproteinemias?

Answer 29

cuz it inhibits lipolysis in adipose tissue and VLDL and LDL synthesis

Question 30

Where is B12 (cobalamin) used in the body? | 2 reactions

Answer 30

AA and odd chain fatty acid metabolism

Question 31

Where can u get B12 in your diet?

Answer 31

meat, fish, dairy and eggs

Question 32

This is a defect in B12 due to a loss of intrinsic factor, which is required fro B12 uptake.

Answer 32

Pernicious anemia

Question 33

What can cause pernicious anemia?

Answer 33

atrophic gastritis or autoimmune destruction of the mucosal cells

Question 34

What are the Sx to pernicious anemia?

Answer 34

anemia, fatigue, depression :(, GI problems (heart burn, diarrhea, etc)

Question 35

What is vitamin C used for in the body?

Answer 35

Synthesis of collagen

Question 36

This disease is from inadequate vitamin C intake.

Answer 36

Scurvy

Question 37

What was the pirate movie rated?????

Answer 37

PG-13

Question 38

What are the Sx to Scurvy?

Answer 38

defective collagen synthesis, so u lose your teeth, impaired wound healing

Question 39

What does vitamin D do in the body?

Answer 39

it's a precursor to a hormone that controls Ca levels in the circulation by controlling GI absorbtion of the Ca, bone resorption of Ca and renal excretion of Ca

Question 40

What is it called when there are weak bones and bowed legs in kids cuz of inadequate vit D intake?

Answer 40

Rickets

Question 41

What is it called when there are soft bones in adults due to inadequate vit D intake?

Answer 41

Osteomalacia

Question 42

What is the role of vit K in the body?

Answer 42

It's important in blood clotting cuz it's a cofactor for gamma-carboxylation of glutamate residues on proteins II, VII, IX, and X.

Question 43

Case: you decide to prescribe a patient warfarin for heart disease. You are also aware vit K is high in leafy greens like spinach. Should you advise the pt to consume more or less of these foods? Why?

Answer 43

LESS! Vit K accelerates clotting mechanisms, so the pt should eat less if you're trying to thin the blood.

Question 44

What are the Sx to vit K deficiency?

Answer 44

prolonged blood clotting --> hemorrhages`

Question 45

What is anemia?

Answer 45

When Hb and Hct are low

Question 46

Normocytic, microcytic, and macrocytic refer to what about the RBC?

Answer 46

it's size

Question 47

Normochromic and Hypochromic refer to what?

Answer 47

The [Hb]

Question 48

So what is going on with microcytic & hypochromatic RBC's?

Answer 48

small RBC's with low Hb

Question 49

What causes anemia with microcytic hypochromatic RBC's?

Answer 49

impaired Hb synthesis

Question 50

What causes impaired Hb synthesis?

Answer 50

iron deficiency, thalassemia mutation, lead poisoning

Question 51

What causes anemia with macrocytic, normochromatic RBC's?

Answer 51

impaired DNA synthesis

Question 52

What causes impaired DNA synthesis?

Answer 52

B12 or folic acid deficiency, erytholeukemia

Question 53

What causes anemia with normocytic and normochromic RBC's?

Answer 53

RBC loss

Question 54

What causes RBC loss?

Answer 54

Bleeding, sickle cell, red cell metabolic disease, red cell membrane defects

Question 55

How much iron is absorbed when we consume 10-50mg a day?

Answer 55

only 10-15% of it

Question 56

Is Fe from meat or plants easier to absorb? Why?

Answer 56

Meat cuz its already in the heme form

Question 57

Is Fe absorbed in the ferrous or ferric state?

Answer 57

Ferrous (Fe2+)

Question 58

What converts the ferrous iron to ferric?

Answer 58

ceruloplasim

Question 59

Why is free Fe always bound to apotransferrin in the blood?

Answer 59

cuz its toxic as shit

Question 60

What is the complex called when Fe binds to apotransferrin?

Answer 60

Transferrin

Question 61

What are the 3 main locations for the storage of Fe?

Answer 61

liver, spleen and bone marrow

Question 62

Once in the tissue, Fe binds with apoferritin to form what?

Answer 62

Ferritin seriosuly can they come up with more names that look exactly alike?