Anatomy help! The influence of blood vessel diameter on peripheral resistance is:

Question

A. insignificant because vessel diameter does not vary B. significant because resistance is directly proportional to the blood vessel diameter C. The only factor that influences resistance D. significant because resistance is inversely proportional to the fourth power of the vessel

and....

Hemorrhage with a large loss of blood causes:

A. no change in blood pressure but a slower heart rate B. a lowering of blood pressure due to change in cardiac output C. no change in blood pressure but a change in respiration D. a rise in blood pressure due to change in cardiac output

one more

Answer 1

Only temporary like in a anti-gravity chamber they would dilate of course

Answer 2

The influence of blood vessel diameter on peripheral resistance is:

A. insignificant because vessel diameter does not vary B. significant because resistance is directly proportional to the blood vessel diameter C. The only factor that influences resistance D. significant because resistance is inversely proportional to the fourth power of the vessel

ANSWER B significant because resistance is directly proportional to the blood vessel diameter. Peripheral resistance is greatest in capillaries which have the narrowest diameter.

and....

Hemorrhage with a large loss of blood causes:

A. no change in blood pressure but a slower heart rate B. a lowering of blood pressure due to change in cardiac output C. no change in blood pressure but a change in respiration D. a rise in blood pressure due to change in cardiac output

ANSWER  B. a lowering of blood pressure due to change in cardiac output .

Hope this helps!

Answer 3

1. Vascular resistance is inversely proportional to the radius to the fourth power.

2. When you bleed a lot your body's blood pressure is decreasing due to an opening in your vessels and blood is leaking out. In order to provide homeostasis, your body will compensate by increasing the blood pressure.

Answer 4

The answer to the first question is D.  This is Pouiselle's Law.

The answer to the second question is B.  Loss of blood decreases the cardiac output potentially leading to shock.