Human Blood and Erythrocytes Overview

Study Notes

Blood circulates through vessels, carrying oxygen and nutrients to cells and removing waste products.
Total adult blood volume is approximately 5 liters.
Blood is divided into two main components: plasma (55%) and blood cells (45%).
Plasma is the liquid portion, composed of 90% water and 10% proteins, salts, nutrients, vitamins, hormones, enzymes, gases, electrolytes, and excretory products.
Plasma pH remains stable at around 7.4.
Blood cells are produced in red bone marrow; some white blood cells multiply in lymphoid tissue.
Blood cells types include red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes).

Main function is carrying oxygen to cells; oxygen binds to hemoglobin, an iron-containing pigment.
Small, disk-shaped, and lack a nucleus.
Concentration: approximately 5 million per µL of blood.
Hemoglobin concentration averages 15 g per dL of blood.
Life span is about 120 days, requiring constant replacement.
Production occurs in bone marrow and is regulated by erythropoietin (EPO), a hormone produced in the kidneys.

Lack hemoglobin and are colorless.
Varying shapes, with prominent nuclei.
Total count is approximately 5,000-10,000 per µL, but increases during infection.
Classified into two groups based on presence of granules: granular leukocytes (granulocytes) and agranulocytes.
Granulocytes have visible granules, include neutrophils, eosinophils, and basophils.
- Neutrophils are the most numerous WBC, identified by various-shaped nuclei.
- Eosinophils and basophils respond to allergic reactions and parasites.
Agranulocytes lack visible granules, include lymphocytes and monocytes.
- Lymphocytes are involved in immunity.
- Monocytes are involved in phagocytosis.

Genetically inherited proteins on the surface of red blood cells.
ABO and Rh are important groups.
ABO system includes A, B, AB, and O types; each type has corresponding antibodies.
Rh system includes Rh-positive (+) and Rh-negative (-) types.
Blood type matching is crucial for blood transfusions to avoid immune reactions.
Compatible blood types are determined by cross-matching.
Whole blood, packed red cells, platelets, plasma, or specific clotting factors may be used in transfusions.

The body's defense system against foreign matter.
Nonspecific defenses include unbroken skin, blood-filtering lymphoid tissue, cilia with mucus, bactericidal secretions, and reflexes like coughing/sneezing.
Specific defenses are mounted by the immune system to attack pathogens.
Immune response involves interactions between parts of the lymphatic system and the blood.
Antigens (foreign particles) trigger an immune response involving lymphocytes (a type of WBC.).
T cells mature in the thymus gland and directly attack foreign cells, while macrophages process antigens.
B cells mature in lymphoid tissue and produce antibodies (immunoglobulins) to inactivate antigens.
Antibodies provide long-term immunity to specific organisms.

Suffixes:
- emia/hemia: Condition of blood.
- penia: Decrease/deficiency.
- poiesis: Formation/production.
Roots:
- hem/o, hemat/o: Blood.
- erythr/o, erythrocyt/o: Red blood cell.
- leuk/o, leukocyt/o: White blood cell.
- thromb/o, thrombocyte: Blood clot/platelet.
- immun/o: Immunity.
- azot/o: Nitrogen compounds.
- calc/i: Calcium.
- ferr/o, ferr/i: Iron.
- sider/o: Iron.
- kali: Potassium.
- natri: Sodium.
- ox/y: Oxygen.

Measures of red blood cells, white blood cells, hemoglobin, hematocrit, and erythrocyte sedimentation rates.
CBC, a comprehensive blood count used for various diagnostic purposes.