Ch 18-2 Blood Flashcards
What is blood?
A fluid connective tissue in which living blood cells are suspended in a fluid matrix (plasma).
What are the formed elements of blood?
- Erythrocytes (red blood cells)
- Leukocytes (white blood cells)
- Platelets
What percentage of total blood volume do leukocytes constitute?
Less than 1%
What is diapedesis?
The ability of leukocytes to leave the bloodstream and move into surrounding ECM and tissues.
What are the two major categories of leukocytes?
- Granulocytes
- Agranulocytes
How can you remember the relative abundance of leukocyte types?
N EVER L ET M ONKEYS E AT B ANANAS (Neutrophil, Lymphocyte, Monocyte, Eosinophil, Basophil)
What are the types of granulocytes?
- Neutrophils
- Eosinophils
- Basophils
What is the average lifespan of neutrophils?
5-6 days
What are the primary functions of eosinophils?
- killing parasitic worms
- Associated with inflammation and allergies
What role do basophils play in the body?
Roles in inflammation, allergy, and asthma.
What are the two types of agranulocytes?
- Lymphocytes
- Monocytes
What is the function of T lymphocytes?
Involved in killing diseased self cells (viruses, cancers).
What is the role of B lymphocytes?
Make plasma cells which produce antibodies (immunoglobulins).
Where do all formed elements of blood arise from?
Hematopoietic stem cells.
What stimulates leukopoiesis?
- Interleukins (IL-1 etc.)
- Colony-stimulating factors (CSFs)
What are platelets also known as?
Thrombocytes.
What is the lifespan of platelets?
Approximately 10 days.
What are the three major steps of hemostasis?
- Vascular Spasm
- Platelet Plug Formation
- Coagulation/Clotting
What occurs during vascular spasm?
Smooth muscle contracts, causing vasoconstriction.
What triggers platelet plug formation?
Injury to the vessel lining exposes collagen fibers.
What is the role of fibrin in coagulation?
Forms a mesh that traps red blood cells and platelets, forming the clot.
What is prothrombin activator?
A complex that converts prothrombin to thrombin during coagulation.
What two pathways can generate prothrombin activator?
- Intrinsic pathway
- Extrinsic pathway
What does thrombin do?
Catalyzes the conversion of soluble fibrinogen to insoluble fibrin.
What is clot retraction?
The process by which clots become more compact.
What is fibrinolysis?
The removal of clots.
What are common anticoagulant drugs?
- Heparin
- Aspirin
- Coumadin (Warfarin)
What is hemophilia?
A disorder resulting from genetic mutations in clotting factors.
What are the types of hemophilia?
- Hemophilia A (mutation in factor VIII)
- Hemophilia B (lack of factor IX)
- Hemophilia C (lack of factor XI)
What is leukemia?
A cancer of white blood cells characterized by uncontrolled division of a single cell clone.
What is leukopenia?
Decreased WBC cells, increasing the risk of infection.
What is a thrombus?
A clot formed in an unbroken blood vessel.
What is an embolism?
When an embolus impedes blood flow because it is too large to pass.
What is thrombocytopenia?
A condition characterized by a low platelet count.
What can cause impaired liver function in relation to hemostasis?
The liver cannot synthesize needed amounts of procoagulants.
What is cerebral embolism?
Emboli in the brain that causes stroke
Cerebral embolism occurs when a blood clot or other debris travels through the bloodstream and lodges in a blood vessel in the brain.
What is thrombocytopenia?
A condition characterized by not enough platelets
Thrombocytopenia can arise from bone marrow malignancy, exposure to some drugs and radiation, or a lack of Vitamin K.
What symptoms are associated with thrombocytopenia?
Bleeding from widespread blood vessels, normal movement causes hemorrhaging, small purple skin spots called petechiae
Petechiae are tiny, flat purple or red spots that appear on the skin due to bleeding under the skin.
What causes impaired liver function related to hemostasis?
Liver can’t synthesize needed amounts of procoagulants
Impaired liver function can be due to cirrhosis, hepatitis, or Vitamin K deficiency.
What is a common cause of Vitamin K deficiency in newborns?
Use of antibiotics
Antibiotics can disrupt the gut flora that produce Vitamin K, leading to deficiency.
What are hemostasis disorders?
Conditions that affect the body’s ability to stop bleeding or form blood clots
Hemostasis disorders can include issues like thrombocytopenia and impaired liver function.
