physiology example exam 2

Front

Which of the following statements is/are TRUE?

• The origin of a skeletal muscle is the point of muscle attachment to the skeletal element that doesn’t move when the muscle contracts
• Contraction of skeletal muscle generates heat which contributes to maintaining body temperature
• Cardiac muscle cells differ from skeletal muscle fibers in that cardiac muscle cells lack T-tubules.

Back

both a and b are true

Front

_______ receptors are expressed on the motor end plate of a muscle fiber.

Back

nicotinic

Front

If a normal person at rest has a heart rate of 80 beats per minute and a stroke volume of 70ml, then this person will have a cardiac output of about ______ml/min.

Back

5600

Front

The intrinsic pathway of the coagulation cascade is activated by ______.

Back

Exposure of the collagen in the wall of the blood vessel to blood

Front

Sequence events following the release of acetylcholine (ACh) from the motor axon terminal: 1) Na+/K+ channels open 2) Troponin moves tropomyosin 3) DHP receptors are activated 4) Muscle fiber contracts 5) Muscle Action potential is initiated 6) Sarcoplasmic reticulum releases Ca++ 7) Sarcomere shortens 8) Myosin head completes powerstroke 9) ACh binds to receptors on the motor end plate

Back

9,1,5,3,6,2,8,7,4

Front

In terms of blood vessels, the combined cross-sectional area is highest in the ______, resulting in the relatively_______blood flow velocity compared to that of other vessels.

Back

Capillaries, slowest

Front

Which characteristic is shared by skeletal muscle fibers and smooth muscle cells?

• Voluntary Control
• Presence of multiple nuclei
• Presence of G-Actin
• Presence of T-tubules

Back

Presence of G-Actin

Front

When the body is at rest, the venous side of the circulation contains ____ of the total blood volume.

Back

60%

Front

The power stroke in a muscle fiber is initiated when:

• The DHP receptors are activated.
• An ATP is hydrolyzed by the myosin head.
• The inorganic phosphate ion (Pi) is released from the myosin head.
• The actin is attached to the myosin head.
• The ADP is released from the myosin head.

Back

The inorganic phosphate ion (Pi) is released from the myosin head.

Front

Which of the following is/are TRUE? Cardiac muscle cells do not have T tubules. Increasing the amount of Ca++ that enters a cardiac muscle cell will increase the force of contraction of that cell. The pacemaker cells of the heart express both α and β receptors on their cell membrane. All of the above are true statements. Only a and b are true statements.

Back

Increasing the amount of Ca++ that enters a cardiac muscle cell will increase the force of contraction of that cell.