Week 3 Blood Lymph Flashcards
(28 cards)
What are the components of blood?
Plasma and formed elements (RBCs, WBCs, and platelets).
What are formed elements?
Blood cells and fragments suspended in plasma – RBCs, WBCs, platelets.
What are the main functions of blood?
Transport, pH regulation, clotting, immune defense, and body temperature regulation.
What is haematocrit?
The percentage of blood volume occupied by red blood cells.
What is a normal haematocrit value?
42% for females, 46% for males.
What is the function of red blood cells?
Transport O2 and CO2 via haemoglobin.
What shape are red blood cells and why?
Biconcave discs – increases surface area for gas exchange.
What is haemoglobin?
A protein in RBCs that binds O2 and CO2; made of 2 alpha and 2 beta chains.
What is erythropoiesis?
The formation of RBCs in red bone marrow.
What is the function of white blood cells?
Immune defense and removal of foreign substances and dead cells.
What are the two main types of WBCs?
Granulocytes and agranulocytes.
List the WBCs in order of abundance.
Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils.
What is the function of neutrophils?
Phagocytosis; first to arrive at injury site.
What is the role of eosinophils?
Combat parasites, involved in allergic responses.
What do basophils do?
Release histamine and heparin at injury sites.
What is the role of monocytes?
Circulate then become macrophages in tissues.
What is the function of lymphocytes?
B cells produce antibodies, T cells mediate immunity, NK cells destroy abnormal tissue.
What are platelets?
Cell fragments from megakaryocytes involved in clotting.
What is haemophilia?
A genetic disorder with deficient clotting factor production (usually VIII).
What is lymph?
Interstitial fluid that enters lymphatic capillaries, lacking large plasma proteins.
What structures return excess fluid to the blood?
Lymphatic vessels.
What is the function of lymph nodes?
Filter lymph, remove antigens, and initiate immune response.
What is the function of the thymus?
Produces thymosin and T lymphocytes.
What does the spleen do?
Filters blood, recycles RBCs, and activates B/T cells.
