Question

question 10
1 pts
____ is used to determine the volume percentage of red blood cells in whole blood.
spectrin
hematocrit
hematopoiesis
hemocytometer
question 11
1 pts
during pregnancy, what happens to the oxygenated blood returned from the placenta via the umbilical vein?
it flows into the inferior vena cava.
it flows into the superior vena cava.
it flows into the ductus venosus.
it flows into the ductus arteriosus.
question 12
1 pts
which of the following vessels do not have the ability to constrict and dilate?
capillaries
arterioles
arteries
veins

Explanation:

• Question 10: Hematocrit is a laboratory test that measures the volume percentage of red blood cells in whole blood. Spectrin is a cytoskeletal protein in red blood cells. Hematopoiesis is the process of blood cell formation. A hemocytometer is a device used to count cells.
• Question 11: During pregnancy, oxygenated blood from the placenta via the umbilical vein flows into the ductus venosus. The inferior vena cava and superior vena cava return deoxygenated blood to the heart. The ductus arteriosus shunts blood from the pulmonary artery to the aorta.
• Question 12: Capillaries are the smallest blood vessels and do not have smooth muscle, so they cannot constrict and dilate. Arterioles, arteries, and veins have smooth muscle that allows them to constrict and dilate.

Answer:

• Question 10: Hematocrit
• Question 11: It flows into the ductus venosus.
• Question 12: capillaries