Hemoglobin, Porphyrine, Iron metabolism

Question 1

Composition of haemoglobin

Answer 1

• 4 Haems
• 4 polypeptide chains

Question 2

Give the systematic name of Haem

Answer 2

• 1,3,5,8 tetramethyl
• 2,4 divinyl
• 6,7 dipropionyl porphin

1,3,5,8 tetramethyl-2,4 divinyl-6,7 dipropionyl porphin

Question 3

Which structure is circled?

Answer 3

Vinyl-group

Question 4

Which structure is circled?

Answer 4

Methine bridge

Question 5

Which structure is circled?

Answer 5

Propionate-group

Question 6

What does the red line indicate?

Answer 6

The coordination site

Question 7

Give the observed levels of carboxyhaemoglobin (COHb)

Answer 7

• Non-smokers = 0-5%
• Smokers = 10%
• Abnormal = >10%
• Treatment is essential = >40%

Question 8

The first step of haemoglobin synthesis

Answer 8

Rate limiting step

Question 9

Rate limiting step reaction

Answer 9

Aminolevulinic acid synthase (PALP co-factor)

Succinyl + CoA + Glycine → Aminolevulinic acid + HSCoA + CO₂

Question 10

Which pathway is shown?

Answer 10

Haemoglobin synthesis

Question 11

Degradation of Haeme takes place in…

Answer 11

• Spleen
• Liver
• Bone marrow

Completed by cells of the mononuclear phagocyte system (MPS)

Question 12

Title the figure

Answer 12

Enterohepatic circulation of bilirubin

Question 13

Answer 13

Hemolysis → Unconjugated bilirubin + albumin

Question 14

Answer 14

Unconjugated bilirubin + albumin → Unconjugated bilirubin

Question 15

Answer 15

Unconjugated bilirubin → Conjugated bilirubin

Question 16

Answer 16

Conjugated bilirubin → Urobilinogen

Catalysed by bacterial proteases

Question 17

Symptoms of bilirubin in the blood

Answer 17

Icterus/Jaundice

• Prehepatic - Due to haemolysis
• Hepatic - Due to liver disease
• Posthepatic - Due to bile stones

Question 18

Composition of myoglobin

Answer 18

• 1 haem
• 1 polypeptide chain
• O₂ binding protein of the skeletal muscle

Question 19

Absorption of iron is completed by…

Answer 19

Enterocytes

Question 20

Answer 20

Iron Uptake

Intestine

• Iron uptake
• Fe³⁺ → Fe²⁺

Question 21

Answer 21

Nonabsorbed iron is eliminated by the faeces

Question 22

Answer 22

Absorption

Mucosal cells

• Fe²⁺ → Fe³⁺
• Ferritin IC transport

Question 23

Answer 23

Transport

• Plasma*
• 2Fe³⁺ + Transferrin

Question 24

Answer 24

Body distribution

Question 25

Answer 25

**Red Blood Cells** * 70-80% Fe²⁺ haemoglobin

Question 26

Answer 26

**Storage** * 20-25% Fe³⁺ * Ferritin (Soluble) * Haemosiderin (Insoluble)

Question 27

Answer 27

**Muscle** * 5% Fe²⁺ * Myoglobin

Question 28

Answer 28

**Iron Loss** * Desquamation of cells * Loss of: * Hair * Nails * Urine * Sweat * Milk * Occult blood loss

Question 29

Describe Anaemia of piglets because of iron deficiency

Answer 29

1. Iron in sow milk decreases 2. Iron storage of piglets Decreases 3. The growth rate of piglets increases?