L6 Blood Flashcards
What are the Embryonic Connective Tissue ?
Mesenchyme and Mucous CT
Adult Connective Tissue Proper:
- Loose CT, Dense Irregular CT, and Dense Regular CT
Specialized Connective Tissue
- Cartilage, Bone, Adipose Tissue, Blood, Hematopoietic Tissue, and Lymphatic Tissue
Blood
is a fluid specialized connective tissue which consists of cells and an extracellular components
What are the permanent residents ?
- Fibroblasts, Macrophages, Adipose cells, Mast cells ,and Mesenchymal Stem Cells
What are the transient cells that migrate from the blood specialized CT ?
- Lymphocytes. Plasma cells, Neutrophils, Eosinophils, Basophils, and Monocytes
Blood consists of ?
red blood cells, white blood cells and platelets and protein-rich plasma
What are the major proteins in the plasma ?
- albumin, globulins ( non-immune and immunoglobulins), and Fibrinogen
What happens when blood is removed from the circulatory system without addition of anticoagulants ?
It will separate into blood clot and serum
Blood Clot
contains formed elements such as fibrin network ( an insoluble protein) with trapped cells
Serum
is plasma that lacks coagulation factors such as fibrinogen ( soluble protein)
Albumin
maintains pressure on the blood vessel wall
“Colloid Osmotic Pressure”
which assures the correct proportion of blood to tissue fluid volume
What happens to the colloid osmotic pressure when albumin leaks out of the blood vessels into the LCT ?
- Decreases and Fluid Accumulates into the tissues
Basic Dyes
- nuclei, granules of basophils, and cytoplasmic RNA
Acid Dyes
- erythrocytes and granules of eosinophils
Erythrocytes Morphology
are very elastic and deformable and can pass through the smallest blood vessels and narrowest capillaries
What do the erythrocytes contain?
- contain hemoglobin
How long do the erythrocytes circulate in the blood for ?
120 days
What does the erythrocytes transport ?
Oxygen and Carbon Dioxide between the lungs and other tissues
What is unique about the disk shape in the erythrocytes ?
- facilitates the gas exchange
- allows more hemoglobin molecules to be close to the plasma membrane
What is the most prevalent hemoglobin group type in adults ?
- 2 alpha and 2 bets chains
What is the main type in the fetus ?
- 2 alpha and 2 gamma
What causes Sickle Cell Disease?
- single point mutation in the gene that encodes beta-globin chain of hemoglobin A (HbA)
Why may the sickle cells lead to obstruction in the vessels ?
- adhere more readily to endothelial surface
- pile in the capillaries
- deprive some parts of the tissues from oxygen and nutrients
What is a consequence of sickle cell anemia ?
stroke
Spectrin
actin-cross-linking proteins , that cross link actin filaments with each other
Erythrocytes Membrane Organization
consists of peripheral membrane proteins and integral membrane proteins
Peripheral Membrane Proteins
composed of cytoskeleton proteins, spectrin
Integral Membrane Proteins
determine blood groups, have attached antigens: A,B,O
Jaundice
yellowing of the skin or the sclera due to excess of the pigment bilirubin because of excessive breakdown of red blood cells
What are the hereditary defects in the erythrocytes ?
- Hereditary Spherocytosis
- Hereditary Elliptocytosis
Hereditary Spherocytosis
spherical shape, mutation of proteins in ankyrin complex
Hereditary Elliptocytosis
- elliptical shape; mutation of spectrin molecules
What are the granulocytes ?
- have granules that stain specifically with certain dyes
- neutrophils, eosinophils, and basophils
Argranulocytes
- show azurophilic granules
- Lymphocytes and Monocytes
Neutrophils
- first line of defense against bacterial infection )innate immunity)
What do the neutrophils contain?
- specific granules ( secondary granules) and azurophilic granules (primary granules)
Where is the heterochromatin in the nucleus ?
periphery of the nucleus
Where is the euchromatin ?
center of the nucleus
Barr Body
repressed X chromosome
What happens when there is inactivation of the second X chromosome ?
- prevent double dose of phenotypic attributes encoded by X chromosome
neutrophils interact with endothelium through ?
their adhesion molecules such as integrin and s-Le carbohydrate on the neutrophils
What are adhesion molecules of the selectins and immunoglobulin superfamily ?
- intracellular adhesion molecule- 1 (ICAM-1) on endothelial cells
What are the integrins activated by ?
- chemokines from endothelial cells bind to ICAM-1
What does the neutrophils do when there is inflammation ?
- more adhesion molecules are induced on the surface on the neutrophils
- Neutrophils extend pseudopods and migrate
Neutrophils migrate how during inflammation
- through opened junction by histamine and heparin released from the mast cells.
When there is a site of injury , what must the neutrophils do ?
- must recognize foreign substance, e.g., bacteria , and phagocytes it
During a blood injury, what happens to the foreign material ?
- specific and azurophilic granules release enzymes, and digest it
What does the specific granules (secondary) consist of ?
- inflammatory response
- contains bacteriostatic and bactericidal agents such as lysozyme
What does the large specific granules contain?
- histamine, heparan sulfate (vasoactive reagents-dilation of small blood vessels).
Where are the vasoactive agents released from ?
- basophils and mast cells
What are the consequences of the vasoactive agents being released ?
- vascular disturbances, hypersensitivity, and anaphylaxis
What causes for the vasoactive agents to be released ?
- antigens bind to immunoglobulins - E (IgE) on the surface of basophils
What are the azurophilic granules
- lysosomes
Mast cells are ?
- large granules with vasoactive : histamine, heparin, and immunoreactive substances
where do mast cells arise from ?
bone marrow stem cells
What is the purpose of the mast cells ?
mediate inflammatory response
What may mast cells cause ?
- systemic hypersensitivity reaction, allergy and anaphylaxis
Major Basic Protein
- eosinophil peroxidase eosinophil-derived neurotoxin
What is the role of the eosinophil cationic proteins?
- directed against helminth parasites
Histaminase
degrade substances released by mast cells and basophils
What are azurophilic granules involved in?
- destruction of parasites and hydrolysis of Antibody-Antigen complexes
When are eosinophils elevated in blood ?
- allergic reaction
- chronic inflammation
- helminthic parasitic infections
What are monocytes transformed into ?
- activated macrophages
What do the monocytes do while in the connective tissue?
- increasing their capacity for phagocytosis
What does the monocytes do to foreign material ?
- ingest microbes (phagocytose)
Where do the monocytes destroy the microbes ?
intracellular vesicles
What do the monocytes become ?
osteoclasts in bone
Where are the macrophages from ?
blood monocytes
What are macrophages ?
- cytoplasm contains granules and/ or vacuoles
- nucleus is irregular
What does the active macrophages have ?
- numerous phagocytic vesicles
- abundant lysosomes
What happens when the lymphocytes get active ?
become active
What are the main functional cells of the lymphocytes ?
- t-cells, b-cells, and natural killer cells (NK)
What is the unique role of the lymphocytes ?
- may re-circulate after leaving the bloodstream
What is the life span of the T-cells ?
- long life-span
What is the T-cell involved in ?
cell-mediated immunity
What is the B-cell involved in ?
activated (plasma cell) produce antibody
Plasma are derived from?
B-cell
What does the rER (basophilia) produce, package, and secrete?
immunoglobulins
What appearance does the nucleus of the plasma have ?
cart wheel
What are the 4 zones of the platelets (thrombocytes) ?
- Peripheral Zone
- Structural Zone
- Organelle Zone
- Membrane Zone
Where the platelets derived from ?
large polyploid megakaryocytes
Cytoplasmic Granules of the “Organelle Zone” :
- serotonin, Histamine, and ADP,
- Fibrinogen, Coagulation Factors,
- Plasminogen, platelet-derived growth factor repair
- blood coagulation and platelet aggregation
What can serotonin do ?
Vasoconstrictor
What is the function of platelets ?
- surveillance of blood vessels, blood clot formation, and repair of injured tissue
What events leading to the restoration of the normal blood flow ?
- Serotonin, vasoconstrictor
- ADP and Thromboxane
- Soluble Fibrinogen is converted to fibrin
What does the ADP and thromboxaneA2 cause ?
- platelet aggregation forming primary hemostatic plug
What does the soluble fibrinogen do ?
- converted to fibrin
- forms loose mesh over the initial plug and secondary hemostatic plug is formed