Final answer:
Portal hypertension is the primary cause of increased bleeding tendencies associated with cirrhosis. Scarring within the liver obstructs blood flow, causing increased pressure in the portal vein and the development of bypass routes that circumvent liver detoxification function.
Step-by-step explanation:
The primary cause of increased bleeding tendencies associated with cirrhosis is portal hypertension. Due to scarring within the liver, blood flow through the liver is obstructed, causing increased pressure in the portal vein. This leads to the development of portal systemic anastomoses, which bypass the liver and allow portal blood to return to the heart without undergoing detoxification. The damaged liver also impairs the detoxification function, further contributing to increased bleeding tendencies.