blood

What are the three main functions of blood?

Transport, regulation, protection

What does blood transport?

O₂, nutrients, hormones, wastes

How does blood regulate the body?

Temperature, pH, fluid volume

How does blood protect the body?

Clotting and immune defense

What are the two main components of blood?

Plasma and formed elements

What are formed elements?

RBCs, WBCs, platelets

What percentage of blood is plasma?

55%

What is hematocrit?

% of RBCs (~45%)

Normal blood pH?

7.35–7.45

Blood volume in average adult?

Males: 5–6 L; Females: 4–5 L

Blood color depends on what?

Oxygen content

What is plasma mostly made of?

90% water

Most abundant plasma solutes by number?

Electrolytes

Most abundant plasma proteins?

Albumin

Function of fibrinogen?

Blood clotting

Main function of RBCs?

Transport O₂ and CO₂

Structure of RBCs?

Biconcave, anucleate, no organelles

What is hemoglobin?

Protein that binds oxygen

Lifespan of RBCs?

100–120 days

Where are RBCs produced?

Red bone marrow

Hormone that stimulates RBC production?

Erythropoietin (EPO)

Key nutrients for RBC production?

Iron, B12, folic acid

What is anemia?

Low oxygen-carrying capacity

What is polycythemia?

Too many RBCs

Cause of sickle-cell anemia?

Abnormal hemoglobin (HbS)

Function of WBCs?

Immune defense

Normal WBC count?

4,800–10,800/µL

What is leukocytosis?

High WBC count

What is leukopenia?

Low WBC count

Two main WBC categories?

Granulocytes and agranulocytes

Most abundant WBC?

Neutrophils (50–70%)

Function of neutrophils?

Phagocytize bacteria

Function of eosinophils?

Kill parasites, allergies

Function of basophils?

Release histamine (inflammation)

Function of lymphocytes?

Immune response (B & T cells)

Function of monocytes?

Become macrophages (phagocytosis)

What are platelets?

Cell fragments for clotting

Platelet function?

Form platelet plug

Normal platelet count?

150,000–400,000/µL

Platelet lifespan?

10 days

What is hemostasis?

Process to stop bleeding

Three steps of hemostasis?

first Vascular spasm, second Platelet plug, third Coagulation

What is a thrombus?

Clot in a vessel

What is an embolus?

Traveling clot

What is DIC?

Widespread clotting + bleeding

When is whole blood used?

Severe, rapid blood loss

What are PRBCs?

Packed red blood cells

Universal donor?

Type O

Universal recipient?

Type AB

What determines blood type?

Antigens on RBCs

What does hematocrit measure?

% of RBCs

What is CBC?

Counts blood cells

What does leukocytosis indicate?

Infection

What does PT test?

Clotting ability