Question

1) You were the top student in your physiology class last semester. For this reason, your professor has asked that you prepare some lectures for her physiology class this semester. Specifically, she would like you to discuss the similarities and differences between the cardiovascular and respiratory systems, in terms of pressure gradients and fluid flow.

Explain how will you describe the role of the following structures: the pump and the tubes.

2) Julia is breathing 14 times per minute, with a tidal volume of 520 mL and a dead space of 152 mL. Lyle is breathing 15 times per minute, with a tidal volume of 400 mL and a dead space of 175 ml. Which patient has better alveolar ventilation?

Answer 1

1)

Cardiovascular system

Blood pressure gradient is the difference in the blood pressure inside the vasculature.The tone of blood vessel plays an important in the regulation of pressure gradients.

1. Smooth muscles of blood vessel normally exhibit tone,a state of prolonged partial contractrion
2. Blood pressure is mostly influenced by the resistance of the blood vessels(arterioles,small arteries etc)
3. The vasoconstriction increases the vascular tone and thereby increases the blood pressure and the vasodialation increases the blood pressure.
4. By altering the activity of vascular smooth muscle the vasoconstrictor and vasodialator agents alter blood pressure.
5. By altering the intracellular calcium concentration in vascular smooth muscle many of the chemicals affects the vascular tone.

Respiratory system

The pressure gradient in pulmonary circulation where the amount of blood ejected by heart is equal to the amount ejected to the systemic circulation.

The factors affecting pulmonary blood flow are

1. pulmonary vascular resistance
2. Gravity
3. Arterial to venous pressure gradient
4. Alveolar pressure

• ​​​​​​​pulmonary vascular resistance is affected by lung volumes,hormones,and oxygen
• Due to the effect of gravity,in upright posture pulmonary blood flow increases from apex to the base of lungs
• The rate of blood flow determines by the pressure differnce between the aterial and venous compartment.
• Alveolar pressure depends on lung volume.Difference in alveolar pressure changes pulmonary blood pressure and floe due to lung volume.

​​​​​​​2)

Julia has better alveolar ventilation

Because here the dead space is low which ia 152ml with a tidal volume of 520ml.so the tidal volue that doesnot take part in gas exchange is less.