Blood Flashcards
Functions of Blood
Transports O2, CO2, nutrients, hormones, wastes
Regulates pH and ion composition by absorbing and neutralizing acids
Restricts fluid loss at injury sites with clotting process
Defends against toxins and pathogens with white blood cells and antibodies
Stabilizes temperature by absorbing heat and distributing blood flow to different areas
Components of Blood
Formed elements - living cells (RBC, WBC, platelets)
Plasma - non-living matrix
Volume of blood in average man/woman?
5 – 6 liters in average male
4 – 5 liters in average female
Physical characteristics of blood include:
Blood is a sticky opaque fluid with a salty metal taste
~5 x thicker than H2O
Oxygen-rich blood is scarlet red
Oxygen-poor blood is dull red/blue
pH 7.35 – 7.45 (alkaline)
Blood temperature is slightly higher than body temperature (38°C or 100.4°F)
Blood plasma is composed of
Composed of:
90% water
7% plasma proteins
3% other solutes
Straw colored fluid – contains over 100 substances (proteins, ions, nutrients, gases, wastes)
Transports organic and inorganic molecules, formed elements, heat
Forms ~55% of whole blood volume
Blood plasma
Plasma proteins in the blood include
Albumin, Clotting proteins/factors (fibrinogen, prothrombin), Globulins
regulates osmotic pressure
keeps water in the blood stream
regulates fluid volume (small assistance with pH)
approx 60% of plasma proteins
Albumin
helps to prevent blood loss when a blood vessel is injured
Clotting proteins/factors (fibrinogen, prothrombin)
helps to prevent blood loss when a blood vessel is injured
Antibodies - help protect the body from pathogens
Lipid carriers - HDL’s and LDL’s
Globulins
Plasma solutes
Electrolytes
Na+, K+, Ca2+, Mg2+, Cl–, HCO3–, HPO4–, SO42–
Organic nutrients
Lipids, carbohydrates, amino acids
Organic wastes
Urea, uric acid, creatinine, bilirubin, ammonium ions
~45% (37–54%) of whole blood (termed Hematocrit)
Main function is to carry O2 – also transport some CO2
Erythrocytes RBC’s
Blood with oxygen bound to hemoglobin
Oxyhemoglobin – bright red
Blood with lots of hemoglobin not bound to oxygen
Deoxyhemoglobin – dark red / blue
Crucial in the body’s defense against disease
Defends the body against bacteria, viruses, parasites, tumors – can move between blood and tissues
Circulate in bloodstream for short period then migrate into loose and dense connective tissue.
Attracted to specific chemical stimuli released by damaged tissues
Surround and destroy the foreign substance by phagocytosis.
Leukocytes WBCs
2 Categories of leukocytes
Granulocytes
Granules in their cytoplasm
Include neutrophils, eosinophils, and basophils
Agranulocytes
Lack cytoplasmic granules
Include lymphocytes and monocytes (macrophages)
WBCs from most to least abundant:
Hint!
Never Let Monkeys Eat Bananas
WBCs from most to least abundant: Neutrophils Lymphocytes Monocytes Eosinophils Basophils
Most common of WBC – 50 to 70%
Life span ~12 hours
Role is phagocytosis
High quantity in exudates
Neutrophils (granulocyte)
<1% of leukocytes
Main role is release of histamine to activate inflammation
Inflammatory chemical that makes blood vessels leaky and leads to chemotaxis
Reason why you get swelling with inflammation/infection
Also releases heparin (anticoagulant) – so blood does not clot with all these extra cells
Basophils (granulocyte)
2 – 4% of leukocytes
Secrete chemicals that destroy certain parasites or allergens
Those with parasite infection or allergic reaction will have elevated eosinophil count
Eosiniphils (granulocyte)
20–40 % of leukocytes
Comprised of B-cells and T-cells (part of immune system)
Lymphocytes (Agranulocytes)
2–8 % of leukocytes
Largest of the white blood cells
Mature into dendritic cells or macrophages
Also eat up the old RBC’s
Monocytes (Agranulocytes)
_____ _____ are present in those tissues that are in contact with the external environment, such as theskinand the inner lining of the nose, lungs, stomach and intestines.
Their main function is to function as antigen presenting cells (APC).
They act as messengers between theinnateand theadaptive immune systems.
Dendritic Cells
Functions of NK cells
NK cells provide rapid responses to viral-infected cells, acting at around 3 days afterinfection, and respond totumorformation.
Typically,immune cellsdetectforeign antigens presented on infected cell surfaces, triggeringcytokinerelease, causinglysisorapoptosis.
NK cells are unique, as they have the ability to recognize stressed cells in the absence ofantibodiesand foreign antigens, allowing for a much faster immune reaction.
Functions of Mast Cells
Mast cells are present in most tissues characteristically surrounding blood vessels and nerves, and are especially prominent near the boundaries between the outside world and the internal milieu, such as theskin and mucosa of therespiratory anddigestive tract.
Contains manygranulesrich inhistamineandheparin.
Best known for their role inallergyandanaphylaxis
Also play an important protective role, being highly involved in wound healing,angiogenesis,immune tolerance, defense againstpathogens, andblood–brain barrierfunction.
Not actually cells – they are fragments of cells
They cling to broken blood vessel or tissue, thus helping to control blood loss
Needed for the clotting process
Low number means more bleeding
High number means clotting
Life span of ~9-12 days
Platelets (thromobocytes)
Hematopoiesis
Definition: blood cell (RBC, WBC, platelets) formation
Occurs in red bone marrow – common sites include skull, pelvis, ribs, sternum, heads of humerus and femur
Bone marrow produces different cells at different rates – does this based on the body needs
What stimulates stem cells in bone marrow to produce RBCs?
Erythropoietin (EPO) is released into plasma when oxygen levels are low (hypoxia) such as with:
Anemia
Declining blood flow to kidneys
Decreased O2 content of air (ex: high altitudes)
Damage to respiratory surface of lungs