Blood Flashcards
Functions of blood
- transportation of oxygen, nutrients, wastes, carbon dioxide, hormones and body heat
- Defense against invasion by pathogens
- Protects against fluid loss by clotting
- Regulatory functions
regulatory functions
- transports body temperature
- proteins dissolved in the plasma maintain osmotic pressure
- Buffers present in blood regulate pH, keeping it constant 7.4
Composition of blood
plasma (55%) + formed elements(45%) = blood
formed elements
- red blood cells/ erythrocytes
- white blood cells/ leukocytes
- platelets/thrombocytes
erythrocytes
red blood cells
leukocytes
white blood cells
thrombocytes
platelets
red blood cell
erythrocytes
white blood cells
leukocytes
platelets
thrombocytes
Plasma is made up of
- water (91%)
- proteins (7%)
- other solutes (2%) : nutrients, wastes, hormones
Three major types of plasma proteins
Albumins, Globulins, Fibrinogen
Solutes in plasma help ____
maintain the osmotic pressure of blood
Plasma proteins are produce by
liver
Plasma proteins create ________ on the blood
create osmotic pressure on the blood
Albumins
- contribute to osmotic pressure more than others
- transport molecules in the blood
Globulins
- some transport substances in the blood
- others such as gamma globulins, fight pathogens
fibrinogen
inactive; when activates forms blood clot
Erythrocytes function
To carry oxygen
Shape of RBC
Biconcave in shape which allows them to squeeze through small capillaries and allow for maximum surface area for gas diffusion
RBC has no nucleus + no organelles in the cytoplasm
Anucleate
RBC contain ____ _____
protein haemoglobin
The _____ portion of Hb binds up to four oxygens
heme / iron
Haemoglobin is a _____- containing proteins that binds oxygens
iron
When bound to oxygen , HB is called ______
oxyhaemoglobin
When oxygen leaves Hb in the tissues, it is called ______
deoxyhaemoglobin
Production of red blood cells occurs in
red bone marrow
Without a nucleus in RBC,
can’t make proteins for cell repair, therefore RBC only live up about 120 days.
Old, worn out RBCs are removed from circulation by
macrophages in the liver and spleen
Name of hormone produce for the production of red blood cells
Erythropoietin (EPO)
process of red blood cell production
A hormone produced by the kidneys called erythropoietin when oxygen levels of the blood are low will stimulates the bone marrow to produce more red blood cells.
Where is leukocytes produced
red bone marrow
Production of leukocytes is regulated by
colony-stimulating factor (CSF)
Function of leukocytes
Fight infection and form an important part of the immune system
Granulocytes and examples
- contain noticeable granules, lobed nuclei
Neutrophils, Eosinophils. Basophils
Agranulocytes and examples
-No granules, non-lobular nuclei
- lymphocytes
- monocytes
Neutrophils
- Have multilobed nucleus
- First responders to baterial infections
- Engulf pathogens by phagocytosis
- able to leave the blood stream -> are found in interstitial fluid and lymph
Eosinophils
-have a bi lobed nucleus and may large granule
Function of eosinophils
to kill parasitic worms and play a role in allergy attacks
Basophils
- have u shaped of lobed nucleus
- in connective tissues basophils and mast cells release histamine during allergic reactions
during allergic reaction what is being released?
-in connective tissues basophils and mast cells release histamine during allergic reactions
two types of Lymphocytes
B and T cells
B cells
when mature, produce antibodies, which mark a pathogen for destruction
T cells
directly destory pathogens
pathogens
a bacterium or virus or other microrganisms that can cause disease
Monocytes
Largest of the WBCs
-In tissues, develop into even larger macophages, which engulf pathogens, old cells and debris
Macrophages
type of phagocyte, responsible for detecting and engulfing & destroying pathogens
Phagocytes
cells that protect the body by ingesting harmful foreign particles , bacteria and dead or dying cells
Thrombocytes results from
fragmentation of large cells called megakaryocytes in the red bone marrow
Platelets are essential for
blood clotting (coagulation)
blood clotting
haemostasis
haemostasis
blood clotting/ stoppage of bleeding resulting from a break in blood vessel
why is haemostasis important
it is important so that plasma and formed elements don’t leak out of broken vessels
what participates in clot formation ?
13 different clotting factors, calcium ions, enzymes
When a vessel breaks____,
platelets clump to partially seal it
clotting factor
prothrombin activator
prothrombin activator (haemostasis)
converts prothrombin to thrombin
what releases prothrombin activator
Platelets and injured tissues release a factor called prothrombin activator, which converts prothrombin to thrombin
______ ions are required to release prothrombin activator
calcium
Three phases of hemostasis
- Vascular spasms
- Platelet plug formation
- Coagulation (blood clotting)
Vascular spasms
Smooth muscle contracts causing vasoconstriction.
Vasoconstriction causes blood vessel to spasm.
Spasms narrow the blood vessel, decreasing blood loss
Describe the process of Platelet plug formation
Injury to lining of vessel exposes collagen fibres
Platelets become sticky and cling to fibers
Anchored platelets release chemicals to attract more platelets
Platelets pile up to form a platelet plug (white thrombus)
platelet plug
white thrombus
What happens in the Coagulation process
Clotting factors present in plasma and released by injured tissues cells interact with CA2+ to form thrombin, the enzyme that catalyzes joining of fibrinogen molecules in plasma to fibrin
fibrin forms a mesh that traps red blood cells and platelets , forming the clot
within the hour, serum is squeezed from the clot as it retracts
Serum is plasma minus clotting proteins
Blood types are determined by
the presence or absence of two antigens, type A and type B on the surface of RBC.
Blood transfusion
transfer of blood from one person to another
agglutination
clumping
to prevent agglutination
need to make sure blood types are compatible
Antigen
a foreign substance, often a glycoprotein, that stimulates an immune response
type A blood has _____ antigen
the A antigen
type B blood has ____ antigen
B
type AB has _____ antigens
A and B
Type O had _____ antigen
neither
Rh positive notation indicates ______
the presence of the Rh antigen
Rh negative indicates
the absence of Rh antigen
Type A blood has ____ surface antigens and plasma has _____
type A surface antigen, anti-B antibodies
Type B blood has ____ surface antigens and plasma has _______
type B surface antigen, anti- A antibodies
Type AB have ______ surface antigens and plasma has
type A and type B surface antigens, neither anti-A and anti-B antibodies
Type O has _______ surface antigens and plasma has _______
neither type A or B surface antigen , plasma has both anti- A and anti-B antibodies
Antibodies are ________
specific and bind only to the antigen they are made for
How agglutination occur
During blood transfusion, if antibodies in the recipient’s plasma bind to antigens on the surface of donated RBC, agglutination occurs
Universal donor
type O
universal recipient
type AB
cross-matching
testing for agglutination of donor RBCs by the recipient’s serum and vice versa
anti-D
anti-Rh
Anemia
too few RBCs or too little Hb
Iron-deficiency anemia
Inadequate intake of dietary iron, so can’t make Hb
Pernicious anemia
lack of vitamin B12, which is needed to make RBCs
Folic-acid-deficiency anemia
need folic acid to make RBCs
Hemolytic anemia
too much hemolysis (rupturing of the RBCs)
Sickle-cell disease
genetic disease that causes RBCs to become sickle-shaped and prone to rupture
Disorders of the white blood cells
- Severe combined immunodeficiency disease
- Leukemia
- Infectious mononucleosis
SCID
an inherited disease in which lymphocytes don’t develop
Leukemia
a group of cancers in which WBCs proliferate without control
Most of the WBCs are abnormal, so don’t function well
Infectious mononucleosis
the Epstein-Barr virus (EBV) infects lymphocytes, resulting in fatigue, sore throat, and swollen lymph nodes
Disorders relating to blood clotting
- Thrombocytopenia
- Thromboembolism
- Hemophilia
Thrombocytopenia
too few platelets due to not enough being made in the bone marrow or the increased breakdown outside the marrow. Can be caused by leukemia or drugs .
Symptoms: excess bleeding
Thromboembolism
when a thrombus forms, travels (embolism) and plugs another vessel
Hemophilia
genetic defiency of a clotting factor. Unable to form clots
