Chapter 27- Blood Flashcards
What percentage of blood is formed elements?What percent of whole blood is plasma?
Plasma 55%
Formed elements- 45%
What is the plasma made up of?
7% proteins
- albumins 57% - maintain osmotic balance (pressure)
- Globulins 38% (ANTIBODIES) protect against antigens
- fibrinogens 4% (CLOTTING)
- prothrombin 1% (CLOTTING)
91% water
2% other solutes
- ions
- nutrients
- waste products
- gases
- regulatory substances
What are the formed elements in blood?
1% platelets
99% erythrocytes
1% leukocytes
- neutrophils 60%-70
- lymphocytes 20-25
- monocytes 3-8
- eosinophils 2-4
- basophils .5-1
What is the purpose of the blood?
Media of transportation
Heat regulation
Connective proposes
What are the main characteristics of red blood cells?
Have no nucleus
Carry hemoglobin
Very few organelles (for structure and shape)
What is the purpose of red blood cells?
Carry oxygen and carbon dioxide (general has exchange)
(Outnumber white blood cells 1000:1)
4-6 million per mm3
What is the the purpose of hemoglobin and how does it work?
Each RBC has 200-300 million hemoglobin globular molecules
4 iron containing heme groups(4 O2 or CO2 binding sites)
What is the normal range for hemoglobin?
140-180 g/L (slightly lower in females)
What are the two disorders relating to hemoglobin?
Anemia- low hemoglobin
Polycythemia- high hemoglobin (disease, respiratory disorder, cancer)
What are the two types of leukocytes and their subdivisions?
Granulocytes
- neutrophils
- eosinophils
- basophils
Agranulocytes
- lymphocytes
- monocytes
What is the main function of leukocytes?
- Defence against disease
- complete cells with nucleus and organelles
- able to move in and out of blood vessels
- respond to chemical released by damaged tissues
What is the normal leukocyte level and what are abnormal levels called?
Normal level- 4000 and 11000 cells per mm3
Leukocytosis- high. Indicates infection
Leukopenia- low. Indicates disease
What are neutrophils and how do they work? What are their characteristics?
Type of granulocyte
- most numerous leukocyte (65%)
- 3-7 lobed nucleus
- highly mobile phagocytic cell to fight off bacterial and fungal infections
Increase during infection
What are basophils and what are their characteristics?
Bilobed nucleus
Found in mucous lining of respiratory and digestive tract
Release chemicals in response to allergies and parasitic worms
What are basophils and what are their characteristics?
Type of granulocyte
Least numerous 0.5-1% of leukocytes
U or S shaped nucleus
Granules contain histamine- released in response to inflammation or allergic reaction
- cause vasodilation (wider veins) > contraction of smooth muscles> capillary walls become permeable to leukocytes to fight reaction
Also contain HEPARIN- anticoagulant to stop clotting
3-7 days to develop
What are lymphocytes and what are their characteristics?
Agranulated leukocyte
Second most numerous leukocyte 25%
Lymph system- immune response to VIRAL INFECTIONS
Large nucleus fills most of cell
Divided into T cells (attack infections directly) and B cells (produce antibodies against specific antigens)
Takes 1-2 days to develop
What are monocytes and what are their characteristics?
Type of Agranulocytes
Largest leukocyte
Kidney shaped nucleus
Clean up dead tissue in liver, lungs, lymph fluid and more
Fight CHRONIC infections
What are thrombocytes and what are some characteristics?
Crucial for clotting (hemostasis)
Normal count 300,000/mm3
What is the process of making blood cells called?
Hematopoiesis
Come from common stem cell hemocytoblast
How long is the RBC life cycle?
100-120 days before macrophage breaks cells down into various biologically useful elements
What are the three phases of hemostasis?
- vascular spasm
- platelet plug formation
- coagulation
Describe stage 1 of hemostasis
Vascular spasm
Injury detected> vasoconstriction of blood vessel to stop blood loss
Platelets release serotonin which causes blood vessel to spasm and constrict, attracts more platelets
Describe step 2 of hemostasis
Collagen fibres are exposed by break of blood vessel
Injured tissue releases THROMBOPLASTIN (acts as clotting factor to initiate coagulation cascade)
Within 1-5 seconds platelet plug will form
Platelets become stick and cling to exposed collagen fibres (temporary platelet plug)
Platelets secrete serotonin which makes them sticky and attracts more
Describe step 3 of hemostasis
Clotting cascade starts with PROTHROMBIN ACTIVATOR
prothrombin interacts with calcium to convert to thrombin
Thrombin interacts with FIBRINOGEN to produce FIBRIN (a fibrous gel that forms mesh like structure that captures RBC to form clot)
