Why is the velocity of blood flow lowest in capillaries?
a. Capillaries are far from the heart, and blood flow starts to slow as it moves away from the heart.
b. The systemic capillaries are supplied by the left ventricle, which has a lower cardiac output than the right ventricle.
c. The total surface area of capillaries is larger than the total surface area of the arterioles.
d. The capillary walls are not thin enough to allow oxygen to exchange with the cells.
e. The diastolic blood pressure is too low to deliver blood to capillaries at a high flow rate.
Answer: c. The total surface area of capillaries is larger than the total surface area of the arterioles.
You might also like to view...
What is in the outer cytoplasmic layer of radiolaria?
a. nucleus b. contractile vacuoles c. algae d. mitochondria e. gas filled vacuoles
The arrival of an action potential at a synaptic terminal causes voltage-gated potassium channels to
open. ____________________ Indicate whether the statement is true or false.
The results in the accompanying figure support the conclusion that:
a. natural selection does not occur in guppies.
b. natural selection can occur in guppies within a few generations.
c. predation is not a selective force in determining the average size of guppies.
d. male body weight increased proportionately more than female body weight.
e. in the experimental setting, the guppies produced fewer, larger offspring.
During the alternation of generations in plants, _____
A) meiosis produces gametes B) mitosis produces gametes C) fertilization produces spores D) fertilization produces gametes