blood background - Sheet1 Flashcards
What is the primary function of albumin in blood?
Maintaining capillary oncotic pressure.
Which serum protein is involved in the inflammatory response?
Globulin.
What is the role of fibrinogen in blood?
Blood clot formation.
Which serum protein is crucial for forming blood clots?
Prothrombin.
What happens to plasminogen, and why is it important?
It is converted to plasmin, which breaks down blood clots; this process prevents perfusion issues.
What are the two major components of blood?
Plasma (55%) and formed elements (45%).
What is the main component of plasma?
Water.
Name some circulating solutes found in plasma.
Electrolytes, nutrients, waste products, gases, glucose, and lipids.
What are the formed elements in blood?
Platelets, leukocytes (WBCs), and erythrocytes (RBCs).
What is hematopoiesis, and where does it primarily occur?
Hematopoiesis is the production of blood cells, primarily occurring in the bone marrow.
What is the difference between red and yellow bone marrow?
Red marrow contains blood stem cells, producing RBCs, WBCs, and platelets, while yellow marrow contains fat and stem cells that can become cartilage, fat, or bone cells.
Which bones in adults contain active bone marrow?
Pelvic bones, vertebrae, cranium and mandible, sternum and ribs, humerus, and femur.
What stimulates the production and release of erythropoietin?
Hypoxia, due to causes such as decreased RBCs, decreased hemoglobin synthesis, decreased blood flow, hemorrhage, or increased O2 consumption by tissues.
Where is erythropoietin produced, and what is its effect?
Produced by peritubular cells in the kidney; it stimulates the bone marrow to increase RBC production and release.
What is thrombopoietin’s role in hematopoiesis?
Thrombopoietin stimulates the production of platelets from megakaryocytes.
Describe endomitosis in platelet development.
In endomitosis, megakaryocytes undergo DNA replication without completing anaphase and cytokinesis, causing nucleus enlargement and resulting in platelet formation.
How are platelets formed from megakaryocytes?
A megakaryocyte expands due to DNA replication and then breaks into fragments known as platelets.
What fraction of platelets enter circulation, and where do the rest reside?
Two-thirds of platelets enter circulation, and one-third reside in the spleen.
How long do platelets circulate before losing their clotting ability?
8-10 days.
Why is the RBC’s ability to change shape important?
RBCs have a biconcave shape that optimizes surface area for gas diffusion and deformability. Their reversible deformity allows them to change to a compact, torpedo-like shape to squeeze through tiny blood vessels (microcirculation) and then return to normal, ensuring efficient oxygen delivery throughout the body.
What is the importance of a reticulocyte count?
A reticulocyte count measures the number of immature erythrocytes (reticulocytes) in the blood, indicating whether new RBCs are being produced. This helps assess bone marrow function and the body’s response to factors like anemia or blood loss.
What role does vitamin C (ascorbic acid) play in erythropoiesis?
Vitamin C helps iron dissolve and be absorbed by creating an acidic environment in the stomach and prevents the oxidation of iron.
What is the function of riboflavin (vitamin B2) in erythropoiesis?
Riboflavin is a coenzyme for erythropoietin production, aiding in the absorption of iron, folic acid, and multiple B vitamins in the digestive tract.
Why is niacin important in erythropoiesis?
Niacin is involved in RBC maturation and is necessary for respiration in mature erythrocytes.
