BIOCHEMISTRY 1

Question 1

Heme is a constituent of many hemoprotiens such as

Answer 1

Hemoglobin
Myoglobin
Cytochrome C & P450
Cytochrome oxidase
Peroxidase
Catalase

Question 2

Heme is an

Answer 2

Iron protoporphyrin

Question 3

Heme consists of

Answer 3

1) Porphyrin
(4 pyrrole rings)

2) Iron

Question 4

Porphyrin is a

Answer 4

Cyclic compound formed of 4 pyrrole rings.

Question 5

The 4 pyrrole rings are linked by

Answer 5

Methenyl or methene bridges
-HC=

Question 6

Iron forms complexes with

Answer 6

Nitrogen atoms of the pyrrole rings of the porphyrin.

Question 7

Reduced porph

Answer 7

Porphyrinogen CH2

Question 8

Oxidized porph

Answer 8

Porphyrin CH

Question 9

Porphyrinogen turns into porphyrin through

Answer 9

Oxidation rxn

Question 10

Site of heme synthesis

Answer 10

1) Bone marrow 85%
For synthesis of hemoglobin

2) Liver 15%
For synthesis of cytochrome P450

Question 11

Rxns of heme synthesis that occur in the mitochondria

Answer 11

The 1st step and last 3 steps

Question 12

The intermediate steps of heme synthesis occur in

Answer 12

The cytosol

Question 13

Heme synthesis doesn’t occur in RBCs, why?

Answer 13

No mitochondria