Ch 18_Exam 1: Blood

Question 1

Blood is made of what two parts?

Answer 1

1. Plasma
2. Formed Elements

Question 2

Plasma is composed of…

Answer 2

90-95% water with the rest being dissolved substances.

Question 3

Name the five items that make up the dissolved substance of plasma.

Answer 3

1. Proteins
2. Nutrients
3. Gases
4. Salts/Electrolytes
5. Wastes

Question 4

The formed elements of blood are composed of…

Answer 4

• Red blood cells / Erythrocytes
• White blood cells / Leukocytes
• Platelets / Thrombocytes

Question 5

_______ stem cells in bone marrow that receive _______ initiate the production of erythrocytes.

Answer 5

Hemopoetic, erythropoetin

Question 6

_______ stem cells in bone marrow that receive _______ initiate the production of leukocytes.

Answer 6

Hemopoetic, interleukins

Question 7

Platelets are fragments of…

Answer 7

Megakaryocytes

Question 8

_______ trigger megakaryocytes to initiate the process of creating thrombocytes/platelets.

Answer 8

Thrombopoietin

Question 9

Hemopoetic stem cells can become ______ or _______.

Answer 9

Erythrocytes or Leukocytes

Question 10

The main purpose of a red blood cell is to…

Answer 10

carry O₂ to the tissues and organs of the body

Question 11

The main purpose of white blood cells is to…

Answer 11

work with the immune system to fight pathogens and infections

Question 12

What are the 3 stages of blood clotting?

Answer 12

1. Vascular spasm
2. Platelet plug formation
3. Coagulation

Question 13

Explain the stage of vascular spasm in the blood clotting process.

Answer 13

• An injury stimulates pain receptors innervating nearby blood vessels to constrict.
• This vasoconstriction is only effective for small blood vessels and lasts only a couple of minutes.
• Platelets release serotonin maintaining vasoconstriction long enough for the last two stages of blood clotting to take effect

Question 14

Serotonin is a chemical _______.

Answer 14

Vasoconstrictor

Question 15

Explain the stage of platelet plug formation.

Answer 15

• With an injury to a blood vessel, the collogen fibers of the vessel wall are exposed
• Platelets attach to these fibers and immediately grow pseudopods that adhere to the vessel wall and other platelets
• The pseudopods contract and draw the walls of the vessel together
• The mass of contracted platelets is the platelet plug

Question 16

The coagulation stage of blood clotting is needed for…

Answer 16

Larger injuries where platelet plug needs reinforcement

Question 17

Explain the stage of coagulation in the blood clotting process.

Answer 17

• Fibrinectin in blood plasma is converted to fibrin via a thrombin enzyme in platelets
• The fibrin then creates a mesh at the injury and closes it

Question 18

What are the two components of blood clotting and briefly explain each.

Answer 18

1. Extrinsic: clotting contributers found outside the blood such as the collagen fibers in the blood vessel walls
2. Intraisic: clotting contributers found inside the blood such as thrombin and fibronectin and platelets

Question 19

Fibrinogen is a precursor to _______ which is a factor used in creating clots.

Answer 19

fibrin

Question 20

Prothrombin is the precursor to _______, a secondary clot forming protein

Answer 20

thrombin