Blood Flashcards
Components of the cardiovascular system
- Blood Vessels, blood and heart.
- Transports nutrients, gases and hormones to cells picks up cellular waste and transports for excretion.
Lymphatic system
- Network of vessels that return the fluid escaped from blood vessels back to bloodstream.
- Includes lymphocytes, lymphoid tissue and lymphoid organs. Fights infections and provides immunity.
Blood’s protective mechanism
Restricts fluid loss through damaged vessels. Platelets in blood and clotting proteins minimize blood loss when vessel is damaged.
Blood’s regulation role
- Regulates pH and electrolyte composition of the interstitial fluids.
- Regulates body temperature.
Blood composition
- 45% hematocrit
- 1% - Buffy coat (platelets and WBCs
- 55% Plasma
Plasma Proteins
- Albumins (60%)
- Globulins (35%)
- Fibrinogen (4%)
- Regulatory Proteins (<1%) (Enzymes, proenzymes, hormones)
Albumin function and components
Major contributors to osmotic pressure of plasma; transport lipids,
and steroid hormones.
Globulin components
(Plasma protein)
Transport ions, hormones, lipids, and immune function
Fibrinogen components
Essential component of the clotting system; can be converted into soluble fibrin.
Plasma Composition and function
- Plasma Proteins (7%)
- Other solutes (1%) (electrolytes, organic nutrients, organic wastes)
- Water (90%)
90% water
Helps regulate body temperature
Contains electrolytes
Transports blood cells, products of digestion and hormones throughout the body
Hematocrit differentiation in males and females.
Males - 47% +/- 5%
Females - 42% +/- 5%
Solute composition of plasma
- Nutrients - Glucose, Amino acids
- Hormones - cortisol and thyroxine
- Wastes - urea
- Blood gases - O2, CO2
Plasma functions
- Water:
* Transport medium; carries heat - Electrolytes:
* Membrane excitability
* Osmotic distribution of fluid b/t ECF & ICF
* Buffering of pH changes - Nutrients, wastes, gases, hormones:
No function – just being transported
Three types of hemopoietic growth factors.
- Erythropoietin - RBCs
- Thrombopoietin - Platelets
- Colony stimulating factors (CSFs) and interleukins - WBCs.
WBC amounts and composition
Human blood contains 4000-11,000 white blood cells per microliter .
- The granulocytes (polymorphonuclear leukocytes, PMNs) are the most numerous.
Young granulocyte morphology
Horseshoe-shaped nuclei and become multilobed as cells grow older.
WBC types in peripheral blood
lymphocytes and monocytes
Platelet functional composition
- lack nuculei
- half life of 4 days
- megakaryocytes form platelets by pinching off bits of cytoplasm and forcing into circulation.
- 60-75% are in circulation, with remainder in the spleen.
Composition of whole blood
RBCs - 99.9%
WBCs and platelets - 0.1%
Plasma - 46-63% volume
Formed elements - 37-54%
Plasma Proteins
(With alpha, beta etc groups)
Most produced in the liver
6-8% of plasma’s total weight
3 groups of plasma proteins
Albumins - Most abundant plasma protein
Globulins -Alpha
Angiotensinogen is an alpha globulin
Many functions, including carrying thyroid hormones
Beta
Plasminogen - Degrades fibrin clots
Transferrin - Mediates transport of iron through the plasma
Gamma - Antibodies
Fibrinogen - Produced in the liver in its inactive form
Cleaved to fibrin which forms the mesh in clotting
Production of formed elements
Hematopoiesis = the process of blood cell production
Stem cell = Cell which all formed elements in a single population are derived from
Proerythroblast
Develop into red blood cells
Myeloblast
Develop into basophils, neutrophils, eosinophils
Monoblasts
Develop into monocytes
Magakaryoblasts
Develop into platelets
General Plasma protein functions
- Maintaining colloid osmotic balance (albumins)
- Buffering pH changes
- Transport of materials through blood (such as water insoluble hormones)
- Antibodies (e.g. gamma globulins, immunoglobulins)
- Clotting factors (e.g. fibrinogen)
Formation of Blood Cells
- Negative feedback systems regulate the total number of RBCs and platelets in circulation
- Abundance of WBC types based of response to invading pathogens or foreign antigens
3.Pluripotent stem cells have the ability to develop into many different types of cells
Hemopoietic Growth Factors
Regulate differentiation and proliferation of blood cells.
a. Erythropoietin – RBCs
b. Trombopoetin – platelets
c. Colony-stimulating factors (CSFs) and interleukins – WBCs
Erythrocytes
- Transport oxygen from lungs to tissues and carbon dioxide from tissues to lungs
- Has no organelles ribosomes or nuclei
- Contains Hemoglobin, Lipids, ATP, carbonic anhydrase
- Each RBC has about 280 million hemoglobin molecules
- Biconcave shape – 30% more surface area for diffusion of O2 across the membrane
- Flexible Membrane- Allows the RBC to travel through narrow capillaries
Hemoglobin
- Oxygen carrying protein.
- Found only in RBCsPigment containing iron -
Appears reddish when oxygenatedAppears bluish when deoxygenated
(In polycythemia may have both. E.g., someone with chronic obstructive pulmonary disease (COPD): hypoxemia stimulates erythropoietin)