Blood

Question 1

What is haematology?

Answer 1

The study of cells and dissolved substances circulating in blood vessels—their origin, functions, and fate.

Question 2

What is the difference between whole blood and peripheral blood?

Answer 2

Whole blood is blood contained in the cardiovascular system; peripheral blood is blood circulating in blood vessels.

Question 3

What is plasma?

Answer 3

The clear liquid component of blood in which cellular components are suspended.

Question 4

What are the functions of blood?

Answer 4

Transportation (O2, nutrients, waste, hormones), regulation (temperature, fluid content, pH), defense (WBCs, platelets).

Question 5

What are the non-cellular and cellular components of blood?

Answer 5

Non-cellular: plasma; Cellular: erythrocytes, leukocytes, thrombocytes.

Question 6

What is the difference between plasma and serum?

Answer 6

Plasma contains clotting factors; serum does not.

Question 7

Where are most plasma proteins synthesized?

Answer 7

In the liver.

Question 8

What are the functions of albumin?

Answer 8

Maintains colloid osmotic pressure and transports substances.

Question 9

What are globulins and their types?

Answer 9

Alpha, beta, and gamma globulins involved in immunity and transport.

Question 10

What is the function of fibrinogen?

Answer 10

Blood clotting.

Question 11

Where does hematopoiesis occur in adults?

Answer 11

Primarily in red bone marrow of skull, ribs, sternum, vertebrae, pelvis, and femurs.

Question 12

What hormone controls erythropoiesis?

Answer 12

Erythropoietin (EPO) from kidneys in response to hypoxia.

Question 13

What are the three types of leukopoiesis?

Answer 13

Lymphopoiesis, monopoiesis, granulopoiesis.

Question 14

What is the precursor of platelets?

Answer 14

Megakaryocyte.

Question 15

Which hormone regulates thrombopoiesis?

Answer 15

Thrombopoietin (TPO).

Question 16

What is the function of erythrocytes?

Answer 16

Transport of blood gases and buffering.

Question 17

What is hemoglobin composed of?

Answer 17

4 subunits, each with a globin and a haem molecule (each binds one O2).

Question 18

What are the two types of hemolysis?

Answer 18

Intravascular and extravascular.

Question 19

What happens during intravascular hemolysis?

Answer 19

RBCs rupture in vessels, releasing hemoglobin which binds to haptoglobin.

Question 20

What happens during extravascular hemolysis?

Answer 20

RBCs are phagocytosed in spleen/liver and broken down into amino acids, iron, and bilirubin.

Question 21

What is the role of transferrin?

Answer 21

Transports iron in the blood.

Question 22

What is hepcidin?

Answer 22

A liver protein that regulates iron by binding to ferroportin.

Question 23

What is ferritin?

Answer 23

The major intracellular storage protein for iron.

Question 24

What is the function of vitamin B12?

Answer 24

Part of enzyme systems, needed for DNA synthesis and erythropoiesis.

Question 25

What is required for B12 absorption?

Answer 25

Intrinsic factor (IF).

Question 26

What are the three types of icterus?

Answer 26

Pre-hepatic (increased hemolysis), hepatic (liver damage), post-hepatic (bile duct obstruction).

Question 27

What is the primary energy source for erythrocytes?

Answer 27

Glucose.

Question 28

What is the glycolytic pathway used for?

Answer 28

ATP production, reduction of methemoglobin, 2,3-BPG production.

Question 29

What is the function of 2,3-BPG?

Answer 29

Decreases hemoglobin’s affinity for oxygen, promoting oxygen release.

Question 30

What is the function of the pentose phosphate pathway?

Answer 30

Produces NADPH for antioxidant protection and ribose for DNA synthesis.

Question 31

What is hematocrit (HCT)?

Answer 31

Percentage of blood volume occupied by RBCs.

Question 32

What causes low HCT?

Answer 32

Overhydration or anemia.

Question 33

What causes high HCT?

Answer 33

Dehydration, polycythemia, or hypoxia.

Question 34

How is oxygen transported in the blood?

Answer 34

1.5% dissolved in plasma, 98.5% bound to hemoglobin.

Question 35

What does the oxygen-hemoglobin dissociation curve represent?

Answer 35

The relationship between PO2 and hemoglobin saturation.

Question 36

What shifts the oxygen dissociation curve to the right?

Answer 36

Decreased pH, increased CO2, increased temp, increased 2,3-BPG.

Question 37

Why does fetal hemoglobin have a left-shifted curve?

Answer 37

It has lower affinity for 2,3-BPG and higher affinity for oxygen.

Question 38

What is methemoglobinemia?

Answer 38

High levels of Fe3+ Hb that cannot bind oxygen, leading to hypoxia.