PHYSIOLOGY AND THE CIRCULATORY SYSTEM - Laboratory - Cracking the AP Biology Exam

Cracking the AP Biology Exam




Lab 10 had three parts.


In lab 10A, students were supposed to know how to measure blood pressure using a sphygmomanometer. In lab 10B, students determined fitness indexes.

What are the general concepts you really need to know?

  • Your heart rate changes with your body position. For example, your heart rate increases as you change from a reclining to a standing position.
  • Your heart rate also increases when you exercise.
  • A blood pressure reading consists of two numbers: a systolic pressure and diastolic pressure. Normal blood pressure for a healthy adult is about 120/80. The numerator is the systolic pressure and the denominator is the diastolic pressure.


In lab 10C, the Q10 value in water fleas, Daphnia, was evaluated. All animals generate heat in metabolism. Water fleas are ectotherms, meaning they get their heat from the environment. Ectotherms regulate their body temperature behaviorally. For example, if it’s too hot, they move to a shady place.

What are the general concepts you really need to know?

  • Fortunately, you don’t have to know about water fleas, per se. What you do have to know is the concept of Q10. Q10 measures the increase in metabolic activity resulting from an increase in body temperature. Because Daphnia can adjust their temperature to the environment, as the temperature in the environment increases, their body temperature also increases. This in turn increases their heartbeat rate per minute. The Q10 was measured for water fleas at various temperatures.

  • All you have to know is that a warm environment can increase the body temperature and heart rate of cold-blooded animals.