true false -3
The function of a pump is to decrease the pressure in a fluid to make the fluid move in the chosen manner.
F
The force pump is more versatile since it relies on atmospheric pressure directly.
F
The heart receives blood from the venous system and raises its pressure to push it out into the arterial system.
T
The right atrium contracts, forcing blood through the tricuspid valve into the right ventricle.
T
When the right ventricle expands, the atrioventricular valve opens to let the venous blood flow into the ventricle, while the semilunar valve remains closed to prevent backflow of previously pumped blood.
T
During the cardiac cycle, pressure within the heart chambers rises and falls with the contraction and relaxation of atria and ventricles.
T
The heart consists of two synchronous force pump
T
When the ventricles contract, pressure inside them increases sharply. This makes the A-V valves close, while the aortic and pulmonary valves open.
T
Many heart problems involve valves, which either have holes in them or do not close completely.
T
If the semilunar valve did not close properly, then the blood would backflow from the venous system during the expansion of the right ventricle.
T
When the circulatory system reaches an equilibrium flow state, thore will be some peake pressure at which blood enters the heart and a base pressure at which blood leaves the heart.
F
The right ventricle is the main pump responsible for the movement of blood around the body.
F
The pressure drop across the arterioles is greater than that across the capillaries.
T
As the resistance to flow increases, the blood volume flow rate decreases.
T
The circulatory system uses the blood pressure and the internal radii of the vessels for the short-term control of volume flow rate.
T
During moderate exercise the blood flow rate may increase by a factor of three, while the blood pressure increases only a small percentage, indicating that the total resistance of the circulatory system has dropped to less than half its previous value.
T
Blood vessel radius is the main determinant of the resistance to flow.
T
Within the normal range of blood pressures and speeds, the blood viscosity does not substantially vary with pressure.
T
Poiseuille's law applies only for laminar flow.
T
In a tube of a certain size, there is a critical speed above which turbulence occurs.
T
The volume flow rate in cm/s is equal to the area in cm^2 multiplied by the average speed of flow in m/s.
F
The speed of flow of a fluid in a closed system is inversely proportional to the area of the "pipes" through which it flows.
T
If the vessel cross sectional area decreases, then the speed will increase.
T
Though the speed of blood as it enters the capillaries is quite small compared to the aortic speed, the pressure is still a considerable fraction of that in the aorta.
T
A smaller vessel can withstand more pressure with a given wall strength.
T
The heart, in pumping, increases the energy of the blood by increasing the pressure and the potential energy
F
When blood flows down to the feet, the gravitational potential energy is reduced and some of it is converted into pressure and kinetic energy, thus helping the heart.
T
If a person's arterial blood pressure is elevated, the heart has to work harder to supply a normal blood volume flow rate.
T
If the vessel wall becomes thickened and loses elasticity, the diastolic pressure drops lower since the elastic rebound is less effective in maintaining the pressure. In this case the difference between systolic and diastolic pressure becomes smaller.
F
The pressure in the circulatory system varies throughout the body.
T