RBC and WBC

Order of centrifuged blood TOP to BOTTOM

Plasma, Buffy coat, erythrocytes

What makes up the Buffy coat of centrifuged blood?

Platelets and WBC

What makes up plasma?

92% water

7% proteins

• Albumin

• Globulins

• Fibrinogen

albumin function

carrier protein for lipid-soluble drugs or steroid hormones

fibrinogen function

inactive protein that activates to fibrin which is involved in clotting

3 functions of blood

-transport o2, co2, hormones

-regulate homeostasis of bodily fluids, ph

-protect against blood loss, and infection

Components of Hemoglobin

Globin- 4 polypeptide chains

Heme pigment- 4 bonded to each globin chain

• Iron central atom which binds to O2

Nitric Oxide effect on red blood cells

Hemoglobin releases this to cause vasodilation to improve blood flow and oxygen delivery

Carbonic anhydrase effect on red blood cells

Catalyzes conversion of carbon dioxide + water to carbonic acid.

70% of carbon dioxide in plasma gets transported in FORM of Carbonic acid

How long do RBC live

~120 days

Removed by liver/spleen

Define Hematopoises

Formation of all blood cells

What is the starting stem cell of all blood cells

Pluripotent stem cell/ hematopoietic stem cell

Define erythropoiesis

Formation of red blood cells/ erythrocytes

What factors stimulate Erythropoiesis?

Hypoxia (not enough oxygen to tissues),

losing blood,

anemia (lack of RBC)

Order of Erythropoiesis

1. Hematopoietic stem cell

2. Myeloid stem cell

3. Proerythroblast

4. Basophilic Erythroblast

5. Polychromatic Erythroblast

6. Orthochromatic Erythroblast

7. Reticulocyte

8. mature cell

Elements needed for Erythropoiesis

Iron, B12, Folic Acid, Erythropoietin, intrinsic factor binds B12 for b12 to be absorbed into blood

Fats, Amino Acids, carbs (for Heme group)

Breakdown of RBC

1. Macrophages engulf, separate HEME, IRON, GLOBIN

2. Iron gets stored for reuse

3. Heme degrades → yellow bilirubin pigment →urobilinogen→ brown pigment stercobilin leaves in feces

4. Globin (a protein) → AA released into circulation

Are WBC nucleated Or anucleated

Nucleated

What are granular WBC

Basophils, Eosinophils, Neutrophils

Contain granules (vesicles) that appear when stained

Define Agranular WBC

Lymphocytes and Monocytes

No visible granules

Leukopoiesis pathways

1. Hemocytoblast stem cell/ hematopoietic/ pluripotent

2. Myeloid Stem cell line- all other blood cells

3. Lymphoid stem cell line- lymphocytes ( B T and NK)

Granulocyte production steps

1. Myeloblasts

2. Promyelocytes

3. Myelocytes- begin to differentiate into either Basophils, Eosinophil or Neutrophil

4. Band cells- fully curved nucleus

5. Mature cell

Physical appearance of Basophil

Large obscuring granules, almost fully purple appear appearance

Physical appearance of eosinophil

Bi-lobed “aviator glasses” shaped nucleus

Physical appearance of neutrophil

3-5 lobes of nucleus ( multiple blobs)

Physical appearance of monocyte

Kidney bean shaped purple

Define thrombopoiesis

Formation of thrombocytes, a.k.a. platelets

Steps to thrombopoiesis

1. Hemocytoblast stem cell → myeloid stem cell line

2. Megakaryoblast

3. Promegakaryocyte

4. Megakaryocyte- large

5. Breaks off into fragments= platelets

TIP: -blast before -cyte and Pro- before the mature cell

Agranulocyte production steps

1. Myeloid line

2. Monoblast

3. Promonocyte

4. Monocyte

Functions of basophils

Their granules have heparin and histamines to increase Inflammation

-high count can indicate allergic reaction, leukemia, cancers, or hypothyroidism

Function of eosinophils

Their granules secrete toxic proteins to kill parasites and play a role in type 1 hypersensitivities – allergies

High count indicates allergic reaction, parasitic infection, auto immune disease

Function of neutrophils

First responders, undergoes phagocytosis (engulfing),

oxidative bursts – kills difficult bacteria, but also itself. First engulfs bacteria, converts its oxygen to superoxide → hydroxide radical or hypochlorous acid- poisons the pathogen

NETS – can also eject its own DNA as a sticky web for destruction

High count indicates bacterial infection, burn, stress, inflammation

Which is the most abundant leukocyte?

Neutrophils

Function of T-lymphocytes

Divides into 2 lineages

• T-Helper cells alert and help b-cells to turn into plasma cells

• Cytotoxic T cells- induce apoptosis of pathogens (self-destruction)