Blood and Lymphatic System Quiz

Blood and Lymphatic System

• Blood is approximately 5 liters in an average 70kg individual
• Blood is a protein-rich fluid with cellular components
• Plasma (~55%) is the protein-rich portion of blood
• Formed elements (~45%) are the cellular components of blood
• Formed elements include leukocytes and platelets (<1% of whole blood) and erythrocytes (45% of whole blood)
• Blood is composed primarily of water (90-92%)
• Blood also contains dissolved ions, nutrients, waste products, and proteins
• Albumin is the most abundant plasma protein and maintains blood osmotic pressure.
• Fibrinogen and Prothrombin are necessary for blood clotting
• Antibodies are necessary for immune defense.
• Red blood cells (RBCs) transport oxygen and carbon dioxide. Hemoglobin binds to O2 and CO2. RBCs are biconcave in shape, enabling more surface area for gas exchange. There are 4 to 6 million RBCs per mm³ of whole blood. Lower numbers of RBCs, or hemoglobin, is called anemia.
• White blood cells (WBCs) defend the body against pathogens, destroy dead/dying body cells, and recognize/kill cancerous cells. WBCs are called leukocytes, and there are 5,000-11,000 per mm³ of blood
• Platelets (thrombocytes) function in blood clotting, are formed from fragmentation of megakaryocytes, and last for about 10 days. Platelets are produced at a rate of 200 billion per day.

Blood Plasma Components

• Water (91-92%) is the solvent
• Plasma proteins (albumin, globulins, fibrinogen) regulate blood osmotic pressure and are involved in defense and clotting
• Ions, sugars, and other substances aid metabolism, cell and tissue function, nutrition, and respiration.

Blood - Formed Elements

• Erythrocytes: Transport oxygen and carbon dioxide, contain hemoglobin. 4-6 million per mm³
• Leukocytes: Fight infection, destroy dead/dying cells, and recognize/kill cancerous cells, and are 5,000-11,000 per mm³
• Platelets: Involved in blood clotting, 150,000-300,000 per mm³

Hematopoiesis

• Multipotent stem cells divide to produce specific stem cells (myeloid and lymphoid).
• Myeloid stem cells produce RBCs, platelets, and most WBCs.
• Lymphoid stem cells produce lymphocytes.

Red Blood Cell Regulation

• Kidneys release erythropoietin (EPO) when blood oxygen levels are low.
• EPO stimulates red bone marrow to increase RBC production.
• When blood oxygen levels increase to normal, EPO production decreases.

Red Blood Cell Destruction

• Macrophages engulf and destroy old or damaged RBCs.
• Hemoglobin is broken down into amino acids, iron, and heme.
• Iron is recycled to the bone marrow.
• Heme is converted into bile pigments, which are eliminated in the bile.

White Blood Cells (WBCs)

• Also known as leukocytes
• Different types with various functions (granulocytes and agranulocytes)

Granular Leukocytes

• Neutrophils: Multi-lobed nuclei, phagocytose pathogens
• Eosinophils: Bi-lobed nuclei, combat parasitic worms, and participate in allergic responses
• Basophils: U-shaped nuclei, release histamine and heparin

Agranular Leukocytes

• Lymphocytes: Spherical nuclei, provide specific immunity to pathogens. There are two types: B and T.
• Monocytes: Kidney-shaped nuclei, become macrophages after migrating to tissues, engulf pathogens, and cellular debris. They are the largest WBCs

Platelets (Thrombocytes)

• Formed from fragmentation of megakaryocytes
• Involved in blood clotting
• Produced at a rate of 200 billion per day
• Have no nucleus
• Last about ten days

Lymphatic System

• Consists of lymphatic vessels and lymphatic organs.
• Fluid balance: takes up excess interstitial fluid and returns it to the bloodstream.
• Fat absorption: absorbs fats from the digestive tract and transports them to the bloodstream.
• Defense: helps defend the body against disease.

Lymphatic Vessels

• Begin with close-ended lymphatic capillaries with large pores allowing particles to enter.
• Larger lymphatic vessels have valves to regulate lymph flow.
• Lymph movement largely depends on skeletal muscle contractions.
• Lymphatic vessels merge to form larger vessels that empty into one of two ducts: thoracic duct or right lymphatic duct.
• Lymph from the right side of the body & right upper limb drains into the right subclavian vein.
• Lymph from the lower body, the left side of the head & neck, and left upper limb drains into the left subclavian vein.

Lymphatic Organs (Primary)

• Thymus: Site of T cell maturation.
• Red bone marrow: Site of blood cell production, including stem cells capable of producing blood cells; limited in adults.

Lymphatic Organs (Secondary)

• Lymph node: Filters lymph, and location for lymphocytes to fight infections and attack cancer cells.
• Spleen: Functions as a blood reservoir and removes dead/dying blood cells
• Lymphatic nodules: concentrations of lymphatic tissues that help defend against pathogens (includes tonsils, Peyer's patches, and the appendix).

Blood Types

• ABO blood typing is based on the presence or absence of antigens A and B on the surface of red blood cells (RBCs).
• Type A blood has type A antigens and anti-B antibodies
• Type B blood has type B antigens and anti-A antibodies
• Type AB blood has type A and B antigens and no antibodies
• Type O blood has neither A nor B antigens, and both anti-A and anti-B antibodies
• Rh factor: another important blood group system, presence or absence of the Rh antigen on RBCs affects compatibility.

Hemolytic Disease of the Newborn

• Occurs when an Rh-negative mother carries an Rh-positive fetus.
• Maternal antibodies against the Rh factor attack fetal RBCs, causing hemolysis.
• Prevented by injections of RhoGAM to the mother during pregnancy and after delivery.

Blood Typing Tests

• Blood samples are tested with antibodies against A, B, and Rh antigens to determine blood type. Observed reactions provide the definitive diagnosis.

Test your knowledge on the components and functions of the blood and lymphatic system. This quiz covers topics such as blood composition, cellular elements, and the roles of various proteins. Perfect for students studying biology or health sciences.