Blood Physiology

Which dietary component is needed for the synthesis of DNA and influences the production of RBCs?

• Calcium

• Iron

• Vitamin A

• Folic acid

• Vitamin D

What percentage of the body weight (in kg) is composed of blood? What percentage of this blood is composed of plasma?

• 20%; 55 %

• 20%; 45%

• 7%; 45%

• 7%; 55%

• < 1%; < 1%

Which of the following statements about red blood cells (RBCs) is INCORRECT?

• Mature RBCs lack ribosomes

• The lifespan of RBCs is about 30 days

• Mature RBCs lack nuclei

• RBCs contain hemoglobin

The biconcave shape of RBCs is beneficial because it:

• allows more space for the mature RBCs to accommodate the nucleus.

• makes the RBCS more flexible so they can pass and bend through the smaller bloodvessels more easily.

• prevents diapedesis of RBCs through the walls of the blood capillaries.

• decreases the ratio of cell surface area to volume of the cell and allows for greater functionality

Which of the following conditions can stimulate erythropoietin secretion?

• Low levels of oxygen in blood

• Normal levels of hemoglobin in RBCs

• A high RBC count

• An increased blood flow through the kidneys

Tags

NGSS.HS-LS1-3

Which of the following blood components provide the major defense for our bodies against invading bacteria and viruses?

• red cells

• white cells

• platelets

• hemoglobin

Most of the volume of normal human blood is composed of:

• red cells

• hemoglobin

• plasma

• white cells

The relatively clear liquid medium which carries the other cells of blood is called:

• plasma

• antibody

• lipid

• chyme

Which of the following statements is true concerning human blood?

• The blood of all normal humans contains red and white cells, platelets, and plasma.

• Some human populations normally lack the ability to produce plasma.

• Proteins are not normal components of human blood.

• Human blood can be transfused to other people directly without any complications

Which of the following statements regarding the platelets is correct?

• In the blood they are present in greater number than red cells.

• They secrete the main clotting factors.

• They aggregate in the presence of prostacyclin.

• They will adhere to the walls of damaged blood vessels.