Blood Flashcards
what is the fluid connective tissue of the CardioVascular system?
Blood
The CardioVascular system includes what? (2X)
The CV system also includes a pump (the heart) that circulates the fluid and a series of conducting hoses (the blood vessels) that carry it throughout the body.
What is blood?
Blood is a specialized connective tissue that contains cells suspended in a fluid matrix.
What are the components of blood?
Whole blood is made up of plasma (fluid with dissolved substances) and formed elements (cells and cell fragments).
Can the components of whole blood be separated? Why?
The components of whole blood can be fractionated, or separated, for analytical or clinical purposes.
What does plasma contain? (5×)
Plasma contains significant quantities of dissolved proteins, namely albumins, globulins, and fibrinogen. (The remaining 1% is enzymes and hormones)
Which dissolved protein in plasma is most abundant?
Albumins
What is albumin’s function in plasma?
plasma osmolarity and osmotic pressure; also important for transporting fatty acids, hormones, etc.
What is the 2nd most abundant protein in plasma?
Globulins
What is globulin function in plasma? (4x)
(1) antibodies; (2) transport globulins, which bind small ions, hormones, and substances that are very low soluble in water; (3) apolipoproteins that carry lipids in blood; (4) steroid-binding proteins that transport steroid hormones in blood.
What is the third most abundant protein in plasma?
Fibrinogen
what is fibrinogen function in plasma?
Fibrinogen functions in clotting - clotting factor.
What happens when blood is taken & the blood clotting process?
When blood is taken, blood clotting process begins - the soluble fibrinogen in blood is converted to fibrin (an insoluble protein).
What is the most important blood clotting factor?
fibrinogen
What is the major difference between serum & plasma?
The major difference between serum and plasma is the absence of clotting factors in serum.
The clotting process also removes what from the solution?
Caclium
When the conversion of fibrinogen to fibrin is inhibited with an anticoagulant,
the resultant blood clot looks a little different and the separated fluid is plasma.
Serum is
Plasma - fibrogens
Where do the plasma proteins originate?
The liver
Can liver disorders alter the composition & functional properties of blood? Why?
liver disorders can alter the composition and functional properties of blood. Because The liver synthesizes and releases more than 90% of the plasma proteins,
What are the formed elements of blood? (3x)
The formed elements of blood are made up primarily of red blood cells (RBC), white blood cells (WBC), and cell fragments known as platelets.
How are formed elements produced?
Formed elements are produced in the process of hemopoiesis/hematopoiesis.
What are the 5 blood functions?
- Transporting dissolved gases, nutrients, hormones, and metabolic wastes.
- Regulating the PH and ion composition of interstitial fluids.
- Restricting fluid losses at injury sites.
- Defending against pathogens.
- Stabilizing body temperature.
Do veins, capillaries & arteries have the same basic physical characteristics?
Whole blood from any source—veins, capillaries, or arteries—has the same basic physical characteristics:
What are the basic characteristics of blood? (3x)
- Blood temperature is about 38°C (100.4°F),
- Blood is five times as viscous as water - five times as sticky, five times as cohesive, and five times as resistant to flow as water.
- Blood is slightly alkaline, with a pH between 7.35 and 7.45.
What are the most abundant blood cells?
The most abundant blood cells are the red blood cells (RBCs), AKA erythrocytes,
What are erythrocytes?
the red blood cells (RBCs),
What does red blood cells contain?
These cells contain the red pigment hemoglobin,
What does hemoglobin do?
which binds and transports the O2 and CO2.
The most specialized cells of the body are what?
Red blood cells
Each RBC is a ______________ with a ____________ and ______________
Each RBC is a biconcave disc with a thin central region and a thicker outer margin.
Do RBC have flexible plasma membranes?
Each RBC has very flexible plasma membrane
The biconcave disc shape of RBC allows: (3x)
- A large surface-area-to-volume ratio.
- RBCs can form stacks
- Enables RBCs to bend and flex when entering small capillaries.
The biconcave disc shape of RBC allows a large surface-area-to-volume ratio. (How?)
Each RBC transports oxygen. Oxygen must be quickly absorbed/released as the RBC passes through the capillaries (lungs or peripheral tissues). The greater the surface area per unit volume, the faster the exchange between the RBC’s and the surroundings.
The benefits of being able to RBCs can form stacks is?
RBCs can form stacks and flow through narrow blood vessels.
RBCs form stacks form and dissociate repeatedly.
What would happen if RBCs couldn’t form stacks?
Otherwise - individual cells would bump the walls, bang together, form logjams and restrict blood flow.
Enables RBCs to bend and flex when entering small capillaries. (How?)
Red blood cells are very flexible. By changing shape, individual RBCs can squeeze through capillaries as narrow as 4 μm.
Additional Features of RBC: (3x)
- During maturation, RBC loses any organelle not directly associated with the transport of O2/CO2.
- Mature RBCs are anucleate (without nuclei); without ribosomes; without mitochondria.
- Mature RBCs cannot divide, synthesize protein, have low energy demand, have a short lifespan (~120 days).
Hemoglobin (Hb) have what structure?
a quaternary structure
Each Hb molecule has __________ chains and _____________ chains of polypeptides
Each Hb molecule has two alpha (α) chains and
two beta (β) chains of polypeptides.
Each chain is a globular protein subunit containing a
single molecule of heme, a nonprotein pigment complex that forms a ring.
Each heme unit holds an
iron ion in such a way that the iron can interact with an oxygen molecule, forming oxyhemoglobin, HbO2.
The binding of one O2 molecule to the iron in a heme unit is
reversible.
The oxygen can ____________ from the heme.
can easily dissociate
The amount of O2 bound to hemoglobin depends mostly on ____________ of the plasma.
on the O2 content
When the plasma O2 level is low while CO2 level is high, such as in peripheral capillaries, hemoglobin
releases O2 and binds CO2.
In the lung capillaries, the plasma O2 level is high while CO2 level is low. RBCs
absorb O2 and release CO2.
Anemia is a condition of
low levels of healthy RBCs or insufficient amount of hemoglobin in RBCs.
In anemia, there is not enough ______________ to the peripheral tissues.
enough oxygen delivery
_____________ organ is affected due to oxygen starvation.
Every organ
Anemic individuals become _____________________, and may also become
weak and lethargic; confused, because their brain is affected as well.
With all this wear and tear and no repair mechanisms, a typical RBC has a _________ life span (How long?)
short; 120 days
What causes RBC to die?
either its plasma membrane ruptures or some other damage occurs,
What happens after the RBC dies?
RBCs will be engulfed by phagocytes of the spleen, liver, and red bone marrow.
The continuous elimination of RBCs goes unnoticed, because
new ones enter the bloodstream at a comparable rate.
Erythropoiesis is the formation
of RBCs, and it occurs throughout life.
Embryonic blood cells appear in the bloodstream during the
third week of development.
The embryonic blood cells divide repeatedly and later differentiate into stem cells, like
(hematopoietic stem cells, HSC)
What do Hematopoietic stem cells do?
divide to produce blood cells.
During fetal period, the primary sites of
hemopoiesis are
liver, spleen, and bone marrow.
In adults, RBC formation, or erythropoiesis occurs only in
red bone marrow, also called myeloid tissue.
Only under extreme stimulations, such as _________________ areas of yellow marrow can ________________
such as severe and sustained blood loss; convert to red marrow, increasing the rate of RBC formation.
For RBCs to be produced,
hematopoietic stem cells (HSCs) in the red bone
marrow must divide.
hematopoietic stem cells (HSCs) divide into 2 types of cells called?
(1) myeloid stem cells,
(2) lymphoid stem cells,
myeloid stem cells,
which in turn divide to produce red blood cells and several classes of white blood cells,
lymphoid stem cells,
which divide to produce one class of white blood cells, lymphocytes.
In the red bone marrow, a red blood cell matures in what length of time?
1 week
On day 1, cells destined to become RBCs first
differentiate into
proerythroblasts,
(RBCs) On day 2 and 3 proceed through various
erythroblast stages. During this time, erythroblasts actively synthesize hemoglobin.
(RBCs) After day 4, the erythroblast
sheds its nucleus and becomes a reticulocyte,
(RBCs) Days 5-7. Hemoglobin
Hemoglobin synthesis continues. During this period, the cell continues to synthesize Hb and other proteins.
After 2 days in the red bone marrow, the reticulocyte
enters the bloodstream.
After a final day in circulation, the reticulocytes
complete their maturation and become indistinguishable from other mature RBCs.
Erythropoiesis is directly stimulated by
the hormone erythropoietin (EPO).
Erythropoietin is a _____________ formed by the kidneys and liver.
glycoprotein
Once secrered, EPO circulates
in the plasma.
hypoxia is
When peripheral tissues are exposed to low oxygen,
When hypoxia occurs
more erythropoietin is released into circulation.
conditions that will cause EPO to release include (4x)
(1) anemia; (2) decreased blood flow to the kidneys; (3) oxygen content in the lung declines, due to disease or high altitude; and (4) lung injury.
Once in the bloodstream, EPO travels to
the red bone marrow,
Once in the bloodstream, EPO travels to the red bone marrow, where it
stimulates stem cells and developing RBCs.
EPO has two major effects:
(1) It stimulates division of hematopoietic stem cells (HSC) and erythroblasts, (2) it speeds up the maturation of RBCs, mainly by accelerating Hb synthesis.
Unlike red blood cells, white blood cells (WBCs), or leukocytes, have
nuclei and other organelles, and they lack hemoglobin.
White blood cells help
defend the body against invasion by pathogens.
WBCs also remove
toxins, wastes, and abnormal or damaged cells.
Most of the WBCs in the body are in
connective tissue or in organs of the lymphatic system.
WBCs migrate through the loose and dense connective tissues of the body and only use
the bloodstream as a means of rapid transportation to get to areas of infection or injury.
In general circulating WBCs are only a _______________ fraction of the total WBC population,
small
WBCs have the following functional characteristics: (2x)
- Can migrate out of the bloodstream. When WBCs in the bloodstream are activated, they squeeze between adjacent endothelial cells and enter the surrounding tissue. This process is called diapedesis.
- Attracted to specific chemical stimuli. This is called positive chemotaxis, and will guides WBCs to invading pathogens, damaged tissues, and other active WBCs.
diapedesis is
When WBCs in the bloodstream are activated, they squeeze between adjacent endothelial cells and enter the surrounding tissue.
positive chemotaxis is
when WBCs are attracted to specific chemical stimuli
Traditionally, WBCs have been divided (2x)
(1) granulocytes - neutrophils, eosinophils, and basophils; and (2) agranulocytes - monocytes and
lymphocytes.
the granules in “granular leukocytes” are
secretory vesicles and lysosomes,
the “agranular leukocytes” also contain
vesicles and lysosomes,
Neutrophils, eosinophils, basophils, and monocytes are part of the body’s _______ defense
non-specific
Macrophages are _________
monocytes that have moved out of the bloodstream and have become actively phagocytic.
Lymphocytes, are responsible for ________ defenses
specific
Lymphocytes, mount a ___________ against specific types of invading pathogens or foreign proteins.
counterattack
neutrophils make up the ______ of WBCs
majority (50-70%)
mature neutrophil has a very _________ nucleus with __________
dense, segmented; two to five lobes.
Neutrophils cytoplasm is packed with
pale granules containing lysosomal enzymes and bactericidal (bacteria-killing) compounds.
Neutrophils are highly
mobile.
Which WBC is the first to arrive at the site of an injury.
Neutrophils
Neutrophils are phagocytic cells specialized in
attacking and digesting bacteria that have been “marked” with antibodies or with complement proteins - plasma proteins involved in tissue defenses.
Most neutrophils survive for how long?
10 hours
When actively engulfing debris or pathogens, neutrophils survive for how long?
30 minutes
Eosinophils are what type of cells?
WBCs, and phagocytic cells
Phagocytic cells are what?
Immune cells that play a critical role in both the early and late stages of immune responses
Eosinophils represent what percentage of WBCs?
2-4% small precentage
What makes Eosinophils easy to identify?
The combination of deep red granules and a typically bilobed (two-lobed) nucleus
Eosinophils attack pathogens that are coated with
antibodies
Eosinophils are also phagocytic cells and can
engulf antibody-marked bacteria, protozoa, or cellular debris.
Eosinophils’ primary mode of attack is
the exocytosis of toxic compounds,
Eosinophils’ primary mode of attack is particularly effective against
multicellular parasites
Why are eosinophils’ primary mode of attack effective against multicellular parasites
b/c too big to engulf, such as flukes or parasitic roundworms.
Eosinophils increase in number during what? (2x)
- allergic reactions
- parasitic infection
Eosinophils attracted to where? What do they do there?
sites of injuries; they release enzymes that reduce inflammation produced by mast cells and neutrophils.
Basophils are what percentage of WBCs?
relatively rare, accounting for less than 1%
Basophils migrate to where? What do they there?
migrate to injury sites and cross the capillary wall to accumulate in the damaged tissues. There they discharge their granules into the interstitial fluids.
The granules contain histamine and heparin,
What does histamine do?
dilates blood vessels,
What does heparin do?
compound that prevents blood clotting.
Stimulated basophils release these chemicals into the interstitial fluids to
enhance the local inflammation.
Stimulated basophils also release other chemicals that attract
eosinophils and other basophils to the area.
Monocytes are how big compared to what?
are spherical cells that are nearly twice the diameter of a typical RBC.
What percentage does Monocytes account for?
2-8% of WBCs, small percentage
Do Monocytes remain in the bloodstream, for how long? Where do they go if not in the bloodstream?
Monocyte only temporarily travels in the bloodstream, remaining in circulation for ~ 24 hours before entering peripheral tissues to become a tissue macrophage.
Which WBcs are aggressive phagocytes?
Macrophages
Macrophages (func)
They engulf items as large as or larger than themselves. When active, they release chemicals that attract and stimulate neutrophils, monocytes, and other phagocytic cells. Also, secrete substances that draw fibroblasts into the region.
What do the fibroblasts attracted by macrophages do?
begin producing scar tissue to wall off the injured area.
What percentage of Lymphocytes account for WBCs?
account for 20-40%
Where does Lymphocytes continuously migrate from? (3x)
Lymphocytes continuously migrate from the bloodstream, through peripheral tissues, and back to the bloodstream.
Basophils have numerous granules that stain
darkly with basic dyes
Circulating lymphocytes represent only _____________ of all lymphocytes.
a small fraction
most of your body’s lymphocytes are in ___________of the lymphatic system.
in other connective tissues and in organs
What are three functional classes of lymphocytes?
- T cells
- B cells
- Natural killer (NK) cells
If Monocyte is not in the bloodstream then it is called?
Macrophage
T cells (T lymphocytes) (func)
responsible for cell-mediated immunity, a specific
defense mechanism against invading foreign cells. T cells are also the coordinator of the immune response. T cells enter peripheral tissues and attack foreign cells directly or control the activities of other lymphocytes.
B cells (B lymphocytes) (func)
responsible for humoral immunity, a specific
defense mechanism that involves the production of antibodies. The antibodies are released by the B cells and distributed throughout the body by blood, lymph, and interstitial fluid.
Activated B cells differentiate into ___________ which ___________________
Activated B cells differentiate into plasma cells, which then synthesize and secrete antibodies.
The T cells responsible for cellular immunity must
migrate to their targets,
the antibodies produced by plasma cells in one location can destroy ______________
antigens almost anywhere in the body.
Natural killer (NK) cells (func)
carry out immune surveillance - the detection and destruction of abnormal cells, thus are important in preventing cancer.
Platelets play what role in Cardiovascular system?
Platelets play a major role in a vascular clotting system that also includes plasma proteins and blood vessels.
Platelets, AKA
thrombocytes,
Platelets, appear as
disc-shaped cell fragments.
Platelet Functions (3X)
- Releasing chemicals important to the clotting process.
- Forming a temporary patch in the walls of damaged blood vessels.
- Reducing the size of a break in a vessel wall.
Platelet Functions: Releasing chemicals important to the clotting process. (Means?)
By releasing enzymes and other factors at the appropriate times, platelets help initiate and control the clotting process.
Platelet Functions: Forming a temporary patch in the walls of damaged blood vessels. (How?)
Platelets clump together at an injury site, forming a platelet plug, which can slow blood loss while clotting takes place.
Platelet Functions: Reducing the size of a break in a vessel wall. (How?)
Platelets contain filaments of actin and myosin. After a blood clot has formed, platelet filaments contract to shrink the clot and reduce the size of the break in the vessel wall.
Thrombocytopoiesis means
Platelet Formation
thrombocytopoiesis takes place where?
in the red bone marrow.
What is the producer of platelets?
Producer: megakaryocytes
During development, megakaryocytes continuously synthesize
proteins, enzymes, and membranes to grow to a large size.
They then begin shedding cytoplasm in small membrane-enclosed packets, which are
the platelets
Three substances influence the rate of megakaryocyte activity and platelet formation
(1) thrombopoietin (TPO), which accelerates platelet formation and stimulates the production of megakaryocytes;
(2) interleukin-6 (IL-6), a cytokine that stimulates platelet formation;
(3) multi-CSF, which stimulates platelet production by promoting megakaryocyte formation and growth.
Blood Clotting AKA
Coagulation
The process of hemostasis refers to
the stopping of bleeding and halting the loss of blood through damaged vessel walls. As well as establishing the framework for tissue repair
Hemostasis has three phases:
the vascular phase, the platelet phase, and the coagulation phase.
The end of the process of hemostasis is
clot retraction
The Process of Blood Clotting (4X)
- Vascular Phase
- Platelet Phase
- Coagulation Phase
- Clot Retraction
Clot retraction does what?
pulls the torn edges of the vessel closer together, thus reducing the size of the break and making it easier for fibroblasts, smooth muscle cells, and endothelial cells to complete repairs.
Fibrinolysis is what?
when the repairs proceed, the clot gradually
dissolves
When does Fibrinolysis begin?
when the proenzyme plasminogen is converted to plasmin.
What does plasmin do?
begins digesting the fibrin strands and eroding the clot.
What are Antigens
are substances that can trigger the binding of antibodies- a protective defense reaction/mechanism (i.e., an immune response).
Your plasma membranes contain surface antigen, that your immune system recognizes which means?
your immune system ignores your own surface antigen rather than attacking them as “foreign”.
Can the same surface antigen can be recognized by antibodies in another individual and trigger an immune reaction
Yes
Surface antigens on red blood cells determine
blood type
Your blood type is determined by
the presence or absence of specific surface an7gens in RBC plasma membranes.
The surface antigens involved are
integral membrane glycoproteins
three surface antigens are of particular importance:
A, B, and Rh (or D).
Type A blood has RBCs with surface antigen
A only
Type B has surface antigen
B only
Type AB has
A and B
Type O has
neither A or B
The Rh blood group is based on the presence or absence of the
Rh surface antigen
Rh positive (Rh+) indicates
the presence of the Rh surface antigen
If you have type A blood, your plasma contains
anti-B antibodies,
cross-reaction or transfusion reaction means
When during a transfusion, if an antibody meets its specific surface antigen, the RBCs will be attacked and may break up (hemolyze)
the surface antigens on the donor’s cells are _______ important in determining compatibility than are the antibodies in the donor’s plasma. why?
the surface antigens on the donor’s cells are more important in determining compatibility than are the antibodies in the donor’s plasma. Because cross-reactions between the donor’s plasma and the recipient’s blood cells will not produce significant agglutination. This is because the donated plasma is diluted through mixing with the larger plasma volume of the recipient.
How many pathways are needed for coagulation?
- Extrinsic pathway
- Intrinsic pathways
- Common pathway
