HIS - Blood Flashcards
Fluid connective tissue that circulates through the cardiovascular system
Blood
Components of blood
- cells
- plasma (protein-rich fluid)
Protein-rich fluid component of blood
Plasma
Cellular component of blood
- erythrocytes/RBCs
- leukocytes/WBCs
- thrombocytes/platelets
- deliver O2 and nutrients and transport waste and CO2
- deliver hormones, regulatory substances, immune system cells
- maintain homeostasis
- act as a buffer
- participates in coagulation
- thermoregulation
functions of blood
Volume of RBCs in a sample of blood (packed cell volume = PCV)
Hematocrit (Hct)
Normal male hematocrit
39-50%
Normal female hematocrit
35-45%
Percentage of blood consisting of leukocytes and platelets
1%
buffy coat
leukocytes and platelets
- liquid extracellular component of blood
- >90% H2O by weight - act as a solvent of different solutes
- proteins
- nutrients
- electrolytes
- dissolved gases
- waste
Blood plasma
What does interstitial fluid derive from?
Blood plasma
important plasma proteins
- albumin
- globulins
- fibrinogen
What is serum?
Blood plasma without clotting factors
- Main protein component (50%)
- Made in the liver
- Functions:
- Responsible for concentration gradient between blood and extracellular tissue fluid
- Source of colloid osmotic pressure
- Carrier protein for thyroxine, bilirubin, and barbiturates
Albumin
How does colloid osmotic pressure affect fluid?
Pulls fluid into the blood
2 types of globulins
- immunoglobulins
- non-immune globulins
- largest globulins
- functional immune components (IgM, IgG, IgA, IgE, IgD)
Immunoglobulins (gamma-globulins)
- maintain osmotic pressure and serve as carrier proteins
- include fibronectins, lipoproteins, and coagulation factors
Non-immune globulins (alpha-globulin and beta-globulin)
- largest plasma protein
- made in the liver
- Functions:
- formation of the platelet plug
- interacts w/ thrombin to make fibrin
- cross-linking of fibrin > forms impermeable net that helps prevent further blood loss
Fibrinogen
functional components of blood cells
- erythrocytes
- leukocytes (BENML)
- platelets
- anunucleated cells devoid of typical organelles
- “bags of hemoglobin”
- biconcave disc and very flexible
- binds to O2 for delivery to tissues and CO2 for removal from tissues
- lifespan = 120 days (~1% of RBCs removed each day)
Erythrocytes
Normal erythrocytes count in males
4.5-6 million cells/MCL
Normal erythrocytes count in females
4-5 million cells/mcL
Where are erythrocytes phagocytized?
Spleen, bone marrow, and liver
- anucleated, immature RBCs
- reflects erythroid roliferation
- stains blue
Reticulocytes
Normal reticulocyte count
0.5-1.5% of RBC count
Normal pathway of reticulocytes
Enter circulation > lose polyribosomes > mature as an RBC
- decreased Hb levels
- most caused by reduction in # of RBCs
- insufficient dietary iron, vitamin B12, or folic acid can lead to decreased RBC production
- varying clinical symptoms depending on type
anemia
- point mutation in beta-globin chain of HbA
- glutamate > valine
- becomes HbS
- low O2 or dehydration > Hb precipitates and cells sickle
- 85% in homozygotes
- <40% in heterozygotes = symptomatic
sickle cell disease
Characteristics of sickled RBCs
- blood more viscous
- RBC more fragile
- break down after 20 days (instead of 120 days)
- pile up and occlude small and large vessels (ACS)
- yellow appearance of sclera of eye and skin
- results from buildup of bilirubin (pigment in RBCs) in blood)
- caused by destruction of circulating RBCs
- inherited RBC defects
- pathogenic organisms, animal venoms, chemicals, and drugs
- common in newborns due to inefficiency of newborn liver
jaundice
2 populations of leukocytes
- granulocytes: BEN
- agranulocytosis: LM
Normal count for total leukocytes
5000-10000 cells/mc
Relative amounts of leukocytes in descending order
- Neutrophils
- Lymphocytes
- Monocytes
- Eosinophils
- Basophils
Mnemonic: Never Let Monkeys Eat Bananas
- most numerous of the circulating WBCs: 50-70%
- hallmark: multi-lobed nucleus, general lack of cytoplasmic staining
- “PMNs”: polymorphonuclear neutrophils
- inactive and spherical when circulating; amoeboid during diapedesis w/ ECM
- function: acute inflammation and tissue injury
Neutrophils
Function of neutrophils
- Acute inflammation and tissue injury
- secrete enzymes (granules), ingest damaged tissue, kill invading microorganisms
- recognized and bind to bacteria, foreign organisms, fungi, and other infectious agents
Types of neutrophil granules
- azurophilic granules: lyososomes containing myeloperoxidase (MPO)
- specific granules: various enzyes, complement activators, and antimicrobial peptides
Lysosomes containing myeloperoxidase (MPO)
Azurophilic granules
Various enzymes, complement, activators, and antimicrobial peptides
Specific granules
Passage of WBCs through blood vessels to area of damage/infection
Diapedesis
Steps of diapedesis
- areas of damage/infection release cytokines
- intercellular junctions are loosened in the postcapillary venules
- cell adhesion proteins increased in the vessel wall
- WBCs express ligand and interact with adhesion proteins > slow them down > adhere to vessel wall
- extend trough openings between endothelial cells and migrate out of venule
- diapedesis
Attraction involving chemical mediators
Chemotaxis
- 1/4% of circulating WBCs
- similar size to neutrophils, bi-lobed nucleus
- hallmark: abundance of large, acidophilus granules staining intensely pink or red
- Function:
- phagocytize Ab-Ag complexes
- count increases w/ allergies or parasitic infections
- may mediate chronic inflammation (such as lung tissue in asthmatics)
Eosinophils
- least numerous <1%
- similar size to neutrophil
- lobed nucleus usually obscured by granules
- hallmark: basophilic, specific granules that stain intensely purple
- release vasoactive agents from granules
- supplement function of mast cells
- responsible for type 1 hypersensitivity reaction and anaphylaxis
- allergic infections
Basophils
- 2-8% of circulating WBCs
- hallmark: intensely staining, spherical nucleus with thin, pale blue rim of cytoplasm (small, medium, large lymphocytes)
- differentiate into other effector cells: T-cells, B-cells, NK cells
- think viral and fungal infections
Lymphocytes
- develop in the thymus
- involved in cell-mediated immunity
T-cells
- form and differentiate into bone marrow
- transform into plasma cells to make antibodies
B-cells
programmed to kill virus-infected and/or tumor cell
NK cells
- 2-8% of circulating WBCs
- largest of the WBCs
- indented, horseshoe shaped nucleus with paler cytoplasm (Contain small azurophilic granules)
- precursor cell of mononuclear phagocytic system
- differentiate in tissues in response to inflammation
Monocytes
Differentiation in tissues in response to inflammation
Monocyte leaves vasculature > macrophage > phagocytosis
- small, membrane-bound cytoplasmic fragments
- derived from megakaryocyte (large polyploid cells in the BM)
- contain granules that release platelet-specific proteins
- function in controlling blood loss (homeostasis)
Thrombocytes
Immature neutrophils with banded nucleus rather than lobed nucleus
Bands
When do “bands” increase?
Large increase in myeloid (neutrophil precursor) proliferation due to serious bacterial infection and cancer
why do reticulocytes stain blue?
residual ribosomal RNA retained
What does an increase or decrease in reticulocte count indicate?
pathology or malignancy
identify
erythrocytes
identify
reticulocytes
what condition does this individual have?
anemia
name the condition
sickle-cell anemia
type of cell
neutrophil
label
type of cell
eosinophils
type of cell
basophil
type of cell
lymphocyte
type of cell
monocyte
type of cell
thymocyte
(1. erythrocyte, 2. blood platelets)
type of cell
bands
