Module 2 - Structure and Function of the hematological systm Flashcards
Blood volumes amounts to how many L in adults?
5.5 L
What is the composition of blood?
- It is made up of various cells - suspended in a solution of protein and inorganic materials (plasma).
- Solution is approximately 92% water and 8% solutes
List the functions of blood
- delivery of substances needed for cellular metabolism in the tissues
- removal of wastes
- defence against invading organisms or injury
- maintenance of acid-base balance
Plasma protein accounts for how much percentage in blood for adults?
50-55%
Describe Plasma
- complex liquid - has organic and inorganic parts
- concentration depends on diet, metabolic demand, hormones, and vitamins
How does plasma differ from serum?
Serum is plasma that has been allowed to clot in the lab to remove fibrinogen and other clotting factors that may interfere with diagnostic tests.
What is the function of water in the plasma?
medium for carrying all constituents
What is the function of electrolytes in the plasma?
Maintenance of H2O in extracellular compartment. Acts as buffers and function in membrane excitability
What is the function of protein in the plasma?
Provision of colloid osmotic pressure of plasma, act as buffers
What is the function of CO2 in plasma?
By product of oxygenation; most co2 content is from HCO3- and acts as a buffer
What are the 2 major groups of protein in the plasma?
albumin and globulins
Which organ produces most of plasma proteins?
liver
What do plasma cells in the lymph nodes produce?
antibodies
This protein composes 60% of plasma protein?
Albumin
This protein acts as a carrier molecule for components of blood and medications.
Albumin
What is the key role of albumin?
regulation of the passage of water and solutes through capillaries.
What does the albumin help maintain?
It helps maintain the critical colloidal osmotic pressure (oncotic pressure) that regulates the passage of fluids and electrolytes into the surrounding tissues.
How are globulins classified?
By their movement compared.
What are the different types of globulin?
-alpha globulins (those moving most closely to albumin),
-beta globulins, and gamma globulins (those with the least movement).
This is a major plasma protein that is about 4% of total plasma. It would move between the beta and gamma regions but is removed during the formation of serum.
Fibrinogen
What does the gamma-globulin region mostly consist of?
antibodies
What are the functions of plasma proteins?
- clotting
- defence
- transport
- regulation
What does clotting factors do?
Promote coagulation and stop bleeding from damaged blood vessels.
What is fibrinogen?
Most plentiful of the clotting factors and precursor to fibrin clot.
Most plentiful of the clotting factors and precursor to fibrin clot.
Fibrinogen
What are the proteins that are involved in defence or protection against infection?
antibodies and complement proteins
What does transport proteins do?
Bind an carry a variety of inorganic and organic molecules. These include iron, copper, lipids, and steroid hormones, and vitamins.
What do regulatory proteins do?
Regulatory proteins include a variety of enzymatic inhibitors (e.g., α1-antitrypsin) that protect the tissues from damage, precursor molecules (e.g., kininogen) that are converted into active biological molecules when needed, and protein hormones (e.g., cytokines) that communicate between cells.
What are the inorganic ions in plasma that regulate cell function, osmotic pressure and blood PH.
Electrolytes, Na, K, Calcium, chloride and phosphate.
What are the cellular components of blood?
- Erythrocytes
- Leukocytes
- Platelets.
What is the most abundant cells of the blood.
Erythrocytes.
How much percentage of the blood volume does RBC occupy?
48% in men and 42% in women
What is the main role of RBC?
Tissue oxygenation
What component carries the gases
Hemoglobin
What does the mature erythrocyte lack?
nucleus and cytoplasmic organelle
What are some the things the mature erythrocyte is unable to do?
- It cannot create protein or carry out oxidative reactions
- Does not go mitotic division
What is the lifespan of the erythrocyte?
80-120 days
what is the size and shape of RBC
Its a small disc with a biconcave shape and has the capacity to reversibly deformed.
What are the functions of leukocytes?
- defence
- remove debris
How are leukocytes classified?
Through their structure and function
Name the different types of leukocytes according to their structures
granulocytes and agranulocytes
What are the different types of granulocytes?
- Neutrophils
- Basophils
- Eosinophils
These are all phagocytes
List the different types of Leukocytes according to their function?
Phagocytes and immunocytes.
List agranulocytes that are phagocytes?
monocytes and macrophages
List agranulocytes that are immunocytes?
lymphocytes
What does granulocytes have in their cytoplasm?
they have membrane-bound granules
What do the granules in the granulocytes contain?
- enzymes capable of killing microorganism and catabolizing debris ingested during phagocytosis.
- also holds powerful biochemical mediators with inflammatory and immune functions.
What are the granulocytes capable of in order to get to sites where their action is needed?
Movement through vessel walls (diapedisis)
What is the most numerous granulocyte
Neutrophil
What percentage does neutrophil make up of the total leukocyte count in adults?
60-70%
What are the chief phagocytes of early inflammation?
Neutrophils
What does neutrophils do soon after bacterial invasion or tissue injury?
- Neutrophils migrate out of the capillaries and into the damaged tissue
- At the site of injury, they ingest and destroy contaminating microorganism and debris.
What is the lifecycle of neutrophil?
1-2 days - they are sensitive to the environment in the damaged tissue.
Describe eosinophils?
- They have large coarse granules
- They make up 2-4% of the normal leukocyte count in adults
Using pattern-recognition receptors, what are the eosinophils capable of?
They are capable of amoeboid movement and phagocytosis
What does eosinophil secondary granules contain?
toxic chemicals that are highly destructive to parasites and viruses
During type I hypersensitivity, allergic reactions and asthma are characterized by?
high eosinophil counts
The high eosinophil counts during type I hypersensitivity, allergic reactions and asthma are involved in?
regulation of inflammation and contribute to the destructive inflammatory processes seen in the lungs of persons who have asthma.
How much percentage does basophils make up the leukocytes?
1%
These are immature macrophages
Monocytes
Where are monocytes formed and release?
Bone marrow into the bloodstream.
Where do monocytes move as they mature and change into tissue macrophages?
liver, spleen, lymph nodes, peritoneum, gastro-intestinal tract
These make up 20 - 25% of the total leukocyte count and are primary cells of the immune system?
Lymphocytes
These resemble lymphocytes. They kill some types of tumour cells in vitro and some virus infected cells without prior exposure.
NK cells.
Where do NK cells develop and circulate?
Develop in bone marrow and circulate in the blood
Describe platelet
are not true cells but plate-like or disc-shaped anuclear cytoplasmic fragments
What are platelets essential for
are not true cells but plate-like or disc-shaped anuclear cytoplasmic fragments
How are platelets formed?
They are formed by the breaking up of large (40 to 100µm in diameter) cells known as megakaryocytes
What do platelets hold?
Platelets hold cytoplasmic granules capable of releasing strong mediators when stimulated by injury to a blood vessel
1/3 of the body’s available platelets are found where?
spleen
How long does platelet circulate for?
8-11 days and ages.
What removes platelets?
macrophages, mostly in the spleen
What joins with circulatory system?
Lymphoid system
What are the classification of lymphoid organs?
Primary and secondary
What are the primary lymphoid organs?
Thymus and bone marrow
What are the secondary lymphoid organs?
spleen, lymph nodes, tonsils, peyer patches of the small intestines.
This is the largest lymphoid organ
spleen
What are the functions of spleen?
- It serves as a site of fetal hematopoiesis,
-filters and cleanses the blood by mononuclear phagocytes,
-and starts an immune response to bloodborne microorganisms.
-It is also a reservoir for blood.
What can happen after splenectomy?
-Leukocytosis - This finding suggests that the spleen has some control over the rate of proliferation of leukocyte stem cells in the bone marrow or their release into the bloodstream.
- iron level decreases - reflecting the spleen’s role in the iron cycle.
- The immune response to encapsulated bacteria, which is primarily an immunoglobulin M (IgM) response, may be severely decreased. This decrease results in increased susceptibility to disseminated infections.
- Loss of the spleen results in an increase in morphologically defective blood cells in the circulation. This finding confirms the spleen’s role in removing old or damaged cells.
Lymph nodes are part of which systems?
hematological and immune system
They are the primary sites for the first encounters between these 2 things.
Antigen and lymphocytes
How does lymphocytes enter the lymph node from the blood?
through the postcapillary venules by diapedesis across the endothelial lining
Where does B cell and T Cell migrate to?
B cells tend to migrate to the cortex and medulla of the nodes, while T cells migrate to the paracortex.
These leukocytes live in the lymph nodes.
Macrophages
What are the function of the macrophages in the lymph nodes?
They help filter the lymph of debris, foreign substances, and microorganisms; and supply antigen-processing functions.
What can cause lymph node enlargement?
The B-cell proliferation in response to a great deal of antigen (e.g., during infection) may result in lymph node enlargement and tenderness (reactive lymph node).
What is mononuclear phagocyte system (MPS)?
is made up of monocytes that differentiate without dividing and live in the tissues for months or perhaps years.3
Macrophages for bonemarrow
Monocytes/macrophages
Macrophages for liver
Kupffer cells (inflammatory macrophages)
Macrophages for lung
alveolar macrophages
Macrophages for connective tissue
histiocytes
Macrophages for bone marrow
macrophages
Macrophages for spleen and lymph nodes
fixed and free macrophages
Macrophages for serous and lymph nodes
fixed and free macrophages
Macrophages for nervous system
Microglial cells
Macrophages for kidney
Mesangial cells
Macrophages for bone
Osteoclasts
Macrophages for skin
Langerhans
Macrophages for lymphoid tissue
dendritic cells
What are the functions of the MPS cells that make them play an important fold in defence?
- These cells ingest and destroy (by phagocytosis) unwanted materials.
These materials include foreign protein particles, circulating immune complexes, microorganisms, debris from dead or injured cells, defective or injured erythrocytes, and dead neutrophils.
This MPS cell are specialized for the function of bone resorption; however, they are also known to have phagocytic abilities.
Osteoclast
How much new blood cells do humans require per day?
100 billion new blood cells per day
blood cell production
Hematopoiesis
Where does Hematopoiesis occur?
It occurs in the liver and spleen of the fetus and only in bone marrow (medullary hematopoiesis) after birth.
What is the process involved in hematopoeisis
This process involves the biochemical stimulation of populations of relatively undifferentiated cells to undergo mitotic division (i.e., proliferation) and maturation (i.e., differentiation) into mature hematological cells.
Which cells differentiate fully before entering the blood?
Erythrocytes and neutrophils
Which cells continue to mature in the blood and in secondary lymphatic organs?
Monocytes and lymphocytes
Where is the bone marrow found?
cavities of the bone
What is the primary residence of hematopoietic stem cells.
Bone marrow
What does the bone marrow consist of?
It consists of blood vessels, nerves, mononuclear phagocytes, stromal cells, and blood cells in various stages of differentiation.
What are the 2 kinds of bone marrow?
red, or active (hematopoietic) marrow (also called myeloid tissue); and yellow, or inactive marrow.
What makes inactive marrow appear yellow:
The large quantities of fat in inactive marrow make it yellow.
Where is active marrow found?
In adults, active marrow is found in the flat bones of the pelvis (36%), vertebrae (29%), cranium and mandible (13%), sternum and ribs (10%), upper limb girdle (8%), and in the extreme proximal portions of the femur (4%).
Where is inactive marrow found?
in the cavities of other bones.
How is hematopoietic marrow vascularized?
by the primary arteries of the bones, which end in a capillary network forming large venous sinuses.