Blood 1 Flashcards
Blood is :
A connective tissue composed of cellular elements suspended in an extensive fluid matrix that circulates the CV system
Plasma proteins are the primary difference between
Plasma and the interstitial fluid
erythrocytes are
Red blood cells
-have a lot of them
Leukocytes are
White blood cells
-low amount of them
-includes lymphocytes, monocytes, neutrophils, eosinophils, basophils
Thrombocytes are
Platelets
-low amount
Total blood Volume:
Around 7-8% of total body weight, about 4-5L
70mL/ 1kg females, 80mL/kg males
Hematocrit
40-45% of blood volume
-fraction of the total column occupied by RBCs
Buffy Coat
WBCs and platelets
<1%
Plasma
55-60%
-pale white solution of electrolytes, plasma proteins, CHOs, lipids
Difference in RBCs between male and female is due to
Males have more testosterone which stimulates RBC production and carries more hemoglobin which the iron in it attaches and carries more O2
Hematopoieses
Production of blood cells
-happens in bone marrow in pelvis, spine, ribs cranium, proximal ends of long bones
-begins with hematopoietic stem cell (produces)
-lineage development guided by cytokines (cell signalling molecules)
Cytokines
Proteins or peptides released from one cell that affect growth or activity in another cell
-guides hematopoiesis
Erythropoiesis
RBC production
-by Erythropoietin in kidney cells
-stimulated by low oxygen
Leukopoiesis
Leukocyte (WBC) production
-by Colony- stimulating Factors inn endothelium, fibroblasts of bone marrow, leukocytes
-all types of blood cells, mobilizes hematopoietic cells
Thrombopoiesis
Thrombocyte (platelet) production
-driven by thrombopoietin in the liver
-influences megakaryocytes (platelets)
RBCs/ Eryhtrocytes are the most
Abundant cell type in blood
-about a 4 month lifespan
-distinctive shape increases surface to volume ratio, decreases diffusion distance
RBCs Three Major Tasks:
- Carrying O2 from lungs to systemic tissue
- Carrying CO2 from tissues to lungs
- Assisting in the buffering of acids and bases
The disk shape of RBCs allow them to
Squeeze through capillaries
Respond to osmotic changes
Provide evidence of disease
RBCs mainly consist of
Hemoglobin
-the O2 transport proteins
-about 96%of dry weight
-other 4% of RBCs are cytoskeleton proteins and transmembrane proteins
Globin proteins:
Most are alpha and beta
-fetus is alpha gamma
Delta
70% of what in the body is found in heme groups of hemoglobin
Iron!
-each heme group can bind one O2 molecule, so each hemoglobin having 4 heme groups can carry 4 O2
WBCs (leukocytes) defend against
Infections
WBCS are grouped into 2 major groups
Granulocytes
Non-granule containing lymphocytes and monocytes
Granulocytes
Contain cytoplasmic granules -little vesicles that are visible under microscope
-contain substances or lysosomes
-brief lifespan in blood, <12 hours, but if activated can migrate into tissues for longer time
Granulocytes 3 Classes: Neutrophil
- Neutrophil: most abundant, granules with lysosomal enzymes capable of digesting foreign material (phagocytosis), then broken down by lysosomes
Granulocytes 3 classes: Eosinophil
- Eosinophil: granules contain major basic protein (MBP)- toxic to parasites and other enzymes
-important in response to virus’s and in allergic reactions (exocytosis)
Granulocytes 3 classes: Basophil
Basophil: least common -granules contain histamine, heparin, and proxidase -play a role in allergic reactions
Non Granule Containing Lymphocytes and Monocytes 2 groups:
Lymphocytes: 2nd most abundant after erythrocytes :t-lympho and b-lympho for adaptive immunity
Monocytes: spend life in peripheral tissues developing into macrophages to: Phagocytosis of pathogens or cellular debris, and Present antigens to lymphocytes
T- Lymphocytes (T-Cells) responsible for:
70-80% of all lymphocytes and for cell mediated immunity
-doesn’t involve antibodies
B- Lymphocytes (B-Cells) responsible for:
Humoral immunity
-make antibodies to antigens
-antibodies neutralize or delete them
