Blood Flashcards
What are erythrocytes?
RBC’s
Are non-nucleares cells that use the molecule hemoglobin to carry oxygen from the lungs to peripheral cells and tissues
What do leukocyte function as?
Mediators of inflammatory and immune responses
What are the types of leukocyte?
Neutrophils Eosinophils Basophils Monocytes Lymphocytes Platelets
What is hematocrit?
Volume of packed RBCs expressed as % of total blood volume; normal = 35-50%
What is anemia?
Decreased hemoglobin concentration (decreased concentration of erythrocytes)
What can cause anemia?
Hemorrhage
Low production of RBCs in bone marrow
Iron deficiency
Hemolysis of RBCs
What is polycythemia?
Increased number of erythrocytes
Blood may become too viscous resulting in impaired blood flow
What are erythrocyte membranes formed from?
Lipids, proteins and carbohydrates
What is spectrum for in erythrocytes?
Allows membrane flexibility and results in normal bicóncava shape of RBCs
It functions to per my RBCs to transmit through small diameter lumens of capillaries
What is sickle cell anemia?
An inherited disease causing deoxygenated hemoglobin to clump and form sickle-shaped RBCs
What is hereditary spherocytosis?
An inherited disease resulting in malformed RBCs (sphere-shaped)
Aberrant shape is due to defects in the spectrin molecule
Abnormal cells are engulfed by macrophages from the spleen, liver and bone marrow
What treatment is used for hereditary spherocytosis?
Splenectomy
How are erythrocytes formed?
Immature erythrocytes are formed in bone marrow from uncleared cells that synthesize hemoglobin
Their maturation involves extrusion and loss of the nucleus and loss of mitochondria, ribosome and most cytoplasmic enzymes
The concentration of Hb increases during maturation; once the cell leaves the bone marrow no further Hb is formed
What are reticulocytes?
The last stage of RBC production (1% of RBC)
Contain residual ribosomal RNA visible as cell inclusion
Increased number of reticulocytes indicates an increased need for oxygen, often the result of hemorrhage
What individuals might have high levels of reticulocytes?
Individuals who move to high altitudes
How long do erythrocytes live for?
120 days
What removes old blood from circulation?
Macrophages of the bone marrow
Spleen
Liver
What parts of RBCs are recycled for the formation of new RBCs?
Iron and heme groups
When iron is removed and transported to tissues, what if formed?
Ferritin
What catabolizes heme and where is this located?
Biliverdin catabolizes heme into bilirubin in the liver
What is bilirubin used for?
Bilirubin is a component of bile and is normally stored in the gall bladder
What are leukocyte involves in?
The immune system
What is dipedesis that is used by leukocytes?
The process by which cels leave venues and capillaries by transmitting vessel walls (between endothelial cells) in order to enter connective tissue
What are leukocyte attracted to?
Infected or inflamed tissues by chemotaxis
How do leukocytes travel?
Migrate through tissues using pseudopodia
What are the two types of leukocytes?
Granulocytes
Agranulocytes
What are the granulocytes?
Neutrophils
Eosinophils
Basophils
What are the characteristics for granulocytes?
Usually billowed or multilobed nuclei
Live for only a few days
All have cytoplasmic granules
What are the kind of granules found on granulocytes?
Primary: are lysosomes containing hydrolytic enzymes
Secondary: specific granules differ according to the cell type and have specific functions
What are the agranulocytosis?
Lymphocytes and monocytes
Contain lysosomes
What is the most common type of leukocyte?
Neutrophils
60-70% of total
What are some characteristics of neutrophils?
Aka polymorphonuclear leukocytes (polymorphs)
Bi or multi-lobed nucleus
May contain bar bodies
Stay in blood vessels for 6-7 hours and migrate to CT where they live for 1-4 days
What are the functions of neutrophils?
Involved in acute inflammation
Engulf and destroy bacteria using pseudopodia (forming phagosomes)
Lysosomes produce hydrolytic enzymes to help destroy phagosomes
Pus is a mixture of dead neutrophils and destroyed bacteria
What do the specific granules of neutrophils do?
Fuse to phagosomes to add hydrogen peroxide, myeloperoxidase, halide ions and other substances to help destroy bacteria
What is opsonization?
Antibodies and complement from blood plasma recognize specific bacteria and coat their surface in a process called opsonization
What is neutrophilia?
Increase numbers (or percentage of total leukocyte number) of neutrophils, usually due to bacterial infection
What is neutropenia?
Decreased numbers of neutrophils, due to enlarged spleen leading to abnormally early destruction of neutrophils
What are some characteristics of eosinophils?
2-4% of leukocyte
12-15 micrometers in diameter
Usually bilobed nucleus
Have prominent acidophilic (eosinophilic) granules
What is function of eosinophils?
Allergic reactions
Eosinophilia
Cells phagocytize antigen-antibody complexes formed in allergic responses
Granule inclusion are toxic to parasitic worms
Where are eosinophils found?
SI tract propia, respiratory system (bronchi) and in the uterovaginal tract
What do eosinophils synthesize?
Substances that inactivate histamine and leukotrienes (produced by basophils and mast cells) in order to reduce inflammation reactions
What are some characteristics of basophils?
<0.5% of leukocyte
Large multilobed nucleus
Have prominent basophilic granules
Where are basophils formed?
Bone marrow
What type of responses are basophils responsible for?
Inflammatory response to antigens
What do basophils and mast cells both contain?
Heparin (anticoagulant)
Histamine (vasodilator)
What are some characteristics of lymphocytes?
30% of leukocyte (MC agranular)
6-18 microns in diameter
Large spherical or globular nucleus
What is the function of T lymphocytes?
Cell-mediated immunity: to destroy antigens (foreign cells, virus-infected cells, etc)
What is the function of B lymphocytes?
To mature into plasma cells in the CT and produce antibodies for the humoral immune response
Where are T and B lymphocytes found?
Spleen
Lymph nodes
Lymphatic nodules of the intestines
What leukocyte are the only ones that can return to the circulation after entering ct by diapedesis?
Lymphocytes
What are some characteristics of monocytes?
Less common granular leukocyte (5%)
12-20 microns
Large C-shaped nucleus
Where are monocytes formed?
Bone marrow
When do monocytes transform into macrophages?
After leaving the circulatory system
What do monocytes form?
Kupffer cells of the liver Alveolar macrophages of the lung Osteoclasts in bone marrow Microglia Antigen presenting cells (APCs)
What do APCs do?
Concentrate antigen and present it to the lymphocyte during an immune response
What are the characteristics of platelets?
Anuclear cell fragments
2-4 microns
Derived from megakaryocytes in the bone barrow
Function in clotting, to control hemorragias
Clump together
What are the 3 types of granules of platelets?
Delta
Alpha
Lambda
What do delta granules do?
Contain calcium ions, ATP, ADP; facilitate platelet aggregation and adhesion
What do alpha granules do?
Contain fibrinogen and platelet derived growth factor to facilitate vessel repair, platelet aggregation and blood coagulation
What do lambda granules do?
Contain lysosomal hydrolytic for blot removal
