test 2 Flashcards
what is hematology
the study of blood and blood-forming tissues. This includes the bone marrow, blood, spleen, and lymph system.
what is hematopoiesis
Blood cell production (hematopoiesis) occurs within the bone marrow. Bone marrow is the soft material that fills the central core of bones.
what are two types of bone marrow
yellow (adipose) and red (hematopoietic), and it is the red marrow that actively produces blood cells.
blood and its function
transportation, regulation, and protection. There are two major components to blood: plasma and blood cells.
plasma
is composed primarily of water, but it also contains proteins, electrolytes, gases, nutrients, and waste.
3 types of blood cells
rythrocytes (RBCs), leukocytes (WBCs), and thrombocytes (platelets)
where do the blood cells develop from?
All three types of blood cells develop from a common hematopoietic stem cell within the bone marrow, best described as an immature blood cell that is able to self-renew and to differentiate into hematopoietic progenitor cells.
Erythrocytes
are primarily composed of a large molecule called hemoglobin, which is a complex compound composed of heme (an iron compound) and globin (a simple protein) and binds with oxygen and carbon dioxide.
Erythropoiesis
is the process of RBC production
Hemolysis
destruction of RBCs) by monocytes and macrophages removes abnormal, defective, damaged, and old RBCs from circulation.
Leukocytes
WBCs) appear white when separated from blood. There are five different types of leukocytes, each of which has a different function.
Leukocytes: granulocytes
Granulocytes (neutrophils, eosinophils, basophils): the primary function of the
granulocytes is phagocytosis, a process by which WBCs ingest or engulf any unwanted organism and then digest and kill it. The neutrophil is the most common type of granulocyte.
leukocytes: lymphocytes
Lymphocytes constitute 20% to 25% of WBCs, and originate form stem cells in bone marrow. They form the basis of the cellular and humoral immune responses.
leukocytes: Monocytes
Monocytes constitute 3% to 8% of all WBCs, and are phagocytic cells. They can ingest small or large masses of matter, such as bacteria, dead cells, tissue debris, and old or defective RBCs.
The primary function of thrombocytes
is to initiate the clotting process by producing an initial “platelet plug” in the early phases of the clotting process.
Hemostasis
is a term used to describe the blood clotting process. This process is important in minimizing blood loss when various body structures are injured.
Four components contribute to normal hemostasis
(1) vascular response, (2) platelet plug formation, (3) fibrin clot development of the blood, and (4) clot dissolution.
Fibrinolysis
a method of maintaining blood in its fluid form, is a continual process resulting in the dissolution of fibrin and thus clots.
spleen and role in hematological system
which is located in the upper left quadrant of the abdomen. The role of the spleen can be classified into four general functions: hematopoiesis, filtration, immunological support, and storage.
The lymph system
onsisting of lymph fluid,
lymphatic capillaries,
lymphatic ducts,
and lymph nodes—carries fluid from the interstitial spaces to the blood.
physical exam for hematological system
including an assessment of lymph nodes, liver, spleen, and skin.
The most direct means of evaluating the hematological system
is through laboratory analysis and other diagnostic studies.