Blood Flashcards
(24 cards)
What are the primary functions of blood?
- Transport of gases, nutrients, and waste products
- Transport of processed molecules
- Transport of regulatory molecules
- Regulation of pH and osmosis
- Maintenance of body temperature
- Protection against foreign substances
- Clot formation
These functions are essential for maintaining homeostasis and overall health.
What is the composition of blood?
- Plasma (liquid matrix)
- Formed elements (cells and cell fragments)
The average blood volume is approximately 4-5 L in females and 5-6 L in males.
What percentage of plasma is made up of water, proteins, and other substances?
91% water, 7% proteins, 2% (ions, nutrients, gases, waste products, and regulatory substances)
Plasma proteins include albumin, globulins, and fibrinogen.
What is the main function of albumin in blood plasma?
Transport molecules
Albumin constitutes 58% of plasma proteins.
What role do globulins play in blood plasma?
- Immune system function
- Transport molecules
- Clotting factors
Globulins make up 38% of plasma proteins.
What is serum?
Plasma without the clotting factors
Serum is used in various medical tests and treatments.
What are the main types of formed elements in blood?
- Red blood cells (RBC or erythrocytes) - 95%
- White blood cells (WBC or leukocytes) and platelets - 5%
The formed elements play crucial roles in oxygen transport and immune response.
What is hematopoiesis?
The process of blood cell production
Hematopoiesis occurs in red bone marrow and lymphatic tissue.
What is the shape of red blood cells and its significance?
Biconcave shape increases surface area compared to a flat disk
This shape facilitates efficient gas exchange.
What is hemoglobin and its function?
A pigmented protein responsible for the red color of blood and oxygen transport
Hemoglobin consists of globin, heme, and iron.
What stimulates the production of red blood cells?
Low blood oxygen levels stimulate the formation and release of erythropoietin from the kidneys
Erythropoietin acts on red marrow to increase RBC production.
What are the main functions of white blood cells?
- Protect the body against invading microorganisms and pathogens
- Remove dead cells and debris through phagocytosis
WBCs are crucial for the immune response.
What are the three types of granulocytes?
- Neutrophils - phagocytize microorganisms
- Basophils - release histamine to promote inflammation
- Eosinophils - respond to allergies and destroy worm parasites
Granulocytes contain large cytoplasmic granules.
What are the two types of agranulocytes?
- Lymphocytes - produce antibodies and regulate the immune system
- Monocytes - enlarge into macrophages and phagocytize bacteria
Agranulocytes have very small granules.
What are platelets and their function?
Minute fragments of cells important for preventing blood loss
They are produced in the bone marrow from megakaryocytes.
What are the three mechanisms of preventing blood loss?
- Vascular spasm
- Platelet plug formation
- Blood clotting (coagulation)
These mechanisms are essential for hemostasis.
What occurs during vascular spasm?
Immediate but temporary constriction of a blood vessel due to smooth muscle contraction
Thromboxane and endothelin are involved in this process.
What is the process of platelet plug formation?
Accumulation of platelets that seals small breaks in blood vessels
This is a crucial step in hemostasis.
What is blood clotting?
A network of threadlike protein fibers called fibrin that traps blood cells and fluid
Clotting is essential for stopping bleeding.
What is the difference between transfusion and infusion?
Transfusion is the transfer of blood or blood components; infusion is the introduction of a fluid other than blood
Understanding this distinction is important in medical settings.
What are antigens and antibodies in the context of blood?
Antigens are molecules on the surface of RBCs; antibodies are proteins in plasma
The interaction between antigens and antibodies can lead to agglutination.
What is agglutination?
Incompatibility of antigen and antibody leading to clumping of blood cells
This can have serious implications during blood transfusions.
What are the main blood groups based on the ABO system?
Type A and Type B antigens
The presence or absence of these antigens determines blood type.
What distinguishes Rh positive from Rh negative blood groups?
Rh positive has Rh antigens on RBCs; Rh negative does not have Rh antigens
This classification is important for blood transfusions and pregnancy.
