physiology example exam 2

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.

• both a and b are true

• a, b and c are all true

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

• muscarinic

• α

• nicotinic

• β

• calcium

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.

• 150

• 1500

• 4900

• 5600

• 70

Tags

NGSS.HS-LS1-3

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

• Fibrinogen in the blood

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

• Tissue factor released by blood vessel endothelial cells

• Chemical signals released by platelets

Put events 1-9 in the correct sequence 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

• 9,1,5,6,3,2,8,7,4

• 9,1,5,4,8,2,6,7,3

• 9,3,5,1,6,2,7,4,8,

• 9,1,5,3,6,2,8,7,4

• 9,1,4,8,5,2,6,7,3

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.

• Aorta, slowest

• Arterioles, fastest

• Capillaries, slowest

• Capillaries, fastes

• Veins, slowest

Which of the following characteristics are shared by skeletal muscle fibers and smooth muscle cells?

• Voluntary Control

• Presence of multiple nuclei

• Presence of G-Actin

• Presence of T-tubules

• Both c and d

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

• 29%

• 60%

• 11%

• 75%

• 50%

Tags

NGSS.HS-LS1-3

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.

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.

Tags

NGSS.HS-LS1-7