This video tells us about the heme synthesis mechanism and how alterations in this mechanism can cause porphyria. This video covers the basic questions related to the synthesis and porphyrias with explanations in the end. TIMELINE: 0:20 Introduction 0:30 Question 1 0:45 Question 2 1:27 Ala synthase explanation 1:53 Question 3 2:17 Question 4 5:22 Question 5 6:09 Question 6 9:55 Question 7 10:56 Question 8 11:53 Question 9 12:05 Question 10 12:16 Question 11 12:44 Question 12 13:38 End