Final answer:
Scar tissue in the liver obstructs blood flow. Scar tissue in the liver obstructs normal blood flow through the liver, causing portal hypertension. Venoconstriction increases blood pressure within veins, blood flow, and returns of blood to the heart. The correct option is B.
Step-by-step explanation:
Scar tissue in the liver obstructs blood flow. Due to the presence of scarring, a condition called cirrhosis occurs, which leads to the obstruction of the passage of blood through the liver. This obstruction causes portal hypertension, making it difficult for blood from the intestines to flow through the liver and return to the heart. As a result, portal systemic anastomoses, or shunts, develop and blood bypasses the liver, returning to the heart via another route without undergoing detoxification by the liver.
Scar tissue in the liver obstructs normal blood flow through the liver, causing portal hypertension. Venoconstriction increases blood pressure within veins, blood flow, and returns of blood to the heart.
Scar tissue in the liver, as seen with conditions like cirrhosis, leads to an obstruction of blood flow through the liver. This obstruction causes a condition known as portal hypertension, making it difficult for blood coming from the intestines to pass through the liver and return to the heart. Consequently, alternative pathways or shunts develop, allowing blood to bypass the liver and go directly back to the heart without being detoxified first by the liver. Therefore, the correct answer to how scar tissue in the liver affects blood flow is b) Obstructs blood flow.
Regarding the blood flow within veins, venoconstriction is the narrowing of the veins. When veins constrict, it can lead to an increase in blood pressure within the veins, augment blood flow due to a more forceful push, and enhance the return of blood to the heart. Hence, the answer to question 12, "Venoconstriction increases which of the following?" is d) all of the above.