Final answer:
Phospholipase enzymes in puff adder and rattlesnake venom target the red blood cell membrane, causing cells to rupture, which is lethal.
Step-by-step explanation:
One of the important biochemical targets of puff adder and rattlesnake venom is the red blood cell membrane. The venom contains phospholipase enzymes which catalyze the hydrolysis of the fatty acid on the secondary hydroxyl group of glycerol in the phospholipids that comprise the cell membrane. This reaction produces lysophospholipids, which cannot integrate properly within the lipid-bilayer, leading to the rupture of the red blood cell membranes. Such envenomization can cause significant health risks and potentially be lethal to humans.
The pharmacological effects of natural toxins like snake venom are being researched for medical applications. For instance, components of snake venom have been used to develop drugs for conditions such as hypertension, chronic pain, and diabetes. This demonstrates the potential for turning a dangerous toxin into a therapeutic agent.