The free-flowing blood located in the middle of a blood vessel is called . The free-flowing blood located in the middle of a blood vessel is called . laminar flow gradient flow friction flow lumen flow Request Answer Part B The flow rate of a liquid is . The flow rate of a liquid is . directly proportional to the resistance directly proportional to the pressure gradient inversely proportional to the pressure gradient directly proportional to the pressure gradient and the resistance Request Answer Part C Which of the following is INCORRECTLY matched with the corresponding equipment used in this experiment