Hematology

Question 1

Plasma

Answer 1

55% of blood.
7% proteins, 91% water, 2% other solutions (nutrients, waste products, gases, regulatory substance.)

Question 2

Buffy Coat

Answer 2

Platelets and Leukocytes

Question 3

Formed Elements

Answer 3

Suspended in plasma
Finite lifespan
Originate from stem cells
Erythrocytes (RBCs)
Leucocytes (WBCs)-Granular and Agranular
Thrombocytes (Plts)

Question 4

Serum

Answer 4

refers to blood which has been allowed to clot and then spun to remove clotting factors that may interfere with tests.

Question 5

Plasma proteins

Answer 5

ALBUMIN-Vascular, transport, and metabolic
GLOBULINS-3 types (alpha, beta,
and gamma)
FIBRINOGEN- clotting

Question 6

Hematopoiesis

Answer 6

Begins to form about 5th week of gestation in spleen/liver and then moves to the bone marrow

Starts with pluripotent stem cells (parent cells) then differentiates

Cytokines control proliferation, differentiation and functional activity

Production is regulated by Colony stimulating factors (CSFs):
Erythropoietin (RBCs)
GM-CSF (granulocytes & monocytes)
G-CSF (neutrophils)
M-CSF ( macrophage )
Thrombopoietin (platelets)

Question 7

Erythropoiesis

Answer 7

Synthesis of RBCs, formed in bone marrow.

All RBCs begin as a pluripotent stem cell in the bone marrow that is stimulated to become an erythroid precursor cell.

The precursor goes through a series of changes until it becomes a mature erythrocyte released by the bone marrow.

Question 8

Erythrocytes

Answer 8

Most abundant, Make up about 1/2 of the blood volume

Tissue oxygenation

Contains hemoglobin (Gases, Electrolytes,
Regulate diffusion through the cell membrane)

Has no nucleus, or cytoplasmic organelles (no protein synthesis)

Life span of 120 days

Question 9

Types of Hemoglobin

Answer 9

Hb A - adult (Oxygen carrying protein)
Hb F – fetal
Hb S – sickle cell
Hb A1C - glycosylated

Question 10

Nutritional requirements for adequate synthesis of healthy RBCs include

Answer 10

Protein
Iron-the main nutritional element needed for hemoglobin synthesis
Vitamin B12
Folic acid.

Question 11

Hypoxia

Answer 11

Low oxygen in blood

Question 12

Reticulocyte Count

Answer 12

The number of reticulocytes is a good indicator of bone marrow activity, because it represents recent production of RBCs.

A high reticulocyte count indicates that the bone marrow is working hard to keep up with RBC loss.

Examples of causes: anemia and cancer

Question 13

Role of the Spleen

Answer 13

Is a highly vascular organ, considered tobe the “graveyard of RBCs”.

Also is an organ of immunity.

The spleen removes aged, lysed, and dead RBCs from circulation.
In the spleen, RBCs are broken down into their component parts, which are recycled to make new RBCs.
It sequesters abnormally shaped and hemolyzed RBCs and destroys them.

Question 14

Splenomegaly

Answer 14

occurs when there is a large amount of RBC breakdown occurring in the body.

Question 15

Leukocytes

Answer 15

Normal count = 5 to 10,000
Types:
Granulocytes
Neutrophils
Eosinophils
Basophils
Agranulocytes
Lymphocytes
Monocytes

Function – to combat inflammation and infection

Question 16

Leukocyte Development Stages

Answer 16

Begins with pluripotent stem cells that differentiate into either MYELOID or LYMPHOID cells in the bone marrow.

BLAST CELLS are the immature precursor cells for each line

Granulocytic precursor cells called MYELOBLASTS (have delicate chromatin and blue gray cytoplasm)

PROMYELOCYTES have the same nuclei, and now the cytoplasm has granules.

BANDS are immature cells

Question 17

Granulocytes

Answer 17

Are round and distinctive multi-lobar nuclei

All can be phagocytic because of the cytoplasmic granules
Specific granules : bind neutral, basic or acidic dye components
Azurophilic: lysosomes

Question 18

Neutrophils

Answer 18

AKA: Polymorphonuclear leukocytes (Polys)
Segmented (Segs): Mature
Blasts: Immature

Responsible for host defense against invaders
Account for 60 -70% of total WBC

Only live 2-5 days

Major role: phagocytosis

Die 1-2 days after migrating to site of injury/inflammation

Question 19

Eosinophils

Answer 19

1-3% of total WBC count
Primary role: Ingest antigen-antibody complex
Mediate vascular effects of histamine and serotonin in allergic reactions

Thought to help by releasing chemicals which detoxify the agents causing the reaction

Also work in parasitic reactions by attaching themselves to the parasite and then release hydrolytic enzymes to kill it

Question 20

Basophils

Answer 20

Lowest number of basophils (2%)
Granules contain:
Heparin
Histamine
Other inflammatory mediators

Structurally similar to mast cells

ALLERGIC AND HYPERSENSITIVTY

Question 21

Agranulocytes

Answer 21

No cytoplasmic granules
Types:
Lymphocytes
Monocytes