Heme Synthesis Pathway

The video tutorial explains the heme synthesis pathway, detailing each step and the intermediates involved. It highlights the importance of heme in hemoglobin and cytochrome synthesis, and discusses the regulation of the pathway, including the role of enzymes like Ala synthase and Ferrochelatase. The tutorial also covers how lead can inhibit certain steps, leading to anemia. A mnemonic is provided to help remember the pathway steps.

What is the primary role of heme in the body?

• To store fat

• To transport oxygen

• To transport glucose

• To synthesize proteins

Which system is primarily responsible for detoxification in the liver?

• Digestive system

• Nervous system

• Erythropoietic system

• Hepatic system

What is the starting material for heme synthesis?

• Glucose and oxygen

• Iron and zinc

• Amino acids and lipids

• Glycine and succinyl-CoA

Which enzyme is the rate-limiting step in heme synthesis?

• Cytochrome oxidase

• Porphobilinogen synthase

• Ferrochelatase

• ALA synthase

What metal can inhibit both ALA dehydrase and ferrochelatase?

• Iron

• Zinc

• Lead

• Copper

Which enzyme adds iron to protoporphyrin IX to form heme?

• Porphobilinogen deaminase

• Cytochrome P-450

• ALA synthase

• Ferrochelatase

What mnemonic can help remember the steps of the heme synthesis pathway?

• Heme ladder

• Glycine cycle

• A puck PP

• Iron loop