Lab 3 - Exercise 25: Blood

what are the two main components of blood?

formed elements (45%)

• erythrocytes

• leukocytes

• thrombocytes

plasma (55%)

• water

• lipids

• dissolved substances (electrolytes Na, K, Cl, nutrients, hormones, wastes)

• colloidal proteins

• clotting factors

plasma

fluid portion of the blood; about 91% water; the remainder consists mostly of proteins such as albumins, globuins, and fibrogen

albumins

produced by the liver, make up the majority of the plasma proteins

globulins

some made by plasma cells; make up next largest portion of proteins in plasma

fibronogen

clotting protein; produced by the liver

red blood cells (erythrocytes)

most common cells in blood

• 5 million per cubic millimeter

• NO nucleus

• appear as pink, biconcave disks

• production of red blood cells is called erythropoiesis

• 7.5 micrometers in diameter

• life span of about 120 days before broken down by spleen or liver

platelets

involved in clotting

• about 250 to 400,000 per cubic millimeter of blood

• consist of small purple fragments of megakaryocytes

white blood cells

• about 7,000 per cubic millimeter, with a range of 5,000 to 9,000

• formed in bone marrow tissue

• lifespan varies from a few hours to several months

• capable of ameboid movement (diapedesis) as they squeeze between cells and engulf foreign particles and cellular debris

what are the two subgroups of white blood cells?

• granulocytes

• agranulocytes

granulocytes

• have granules in their cytoplasm

• also known as polymorphonuclear (PNM) leukocytes due to their variable shapes of their nuclei (which are lobed, not round)

neutrophils

most common of all white blood cells

• typically live for about 1-2 days

• ambeiod capabilities

• move by diapedesis between blood capillary cells and in the interstitial areas between the cells of the body

• move toward infection sites and destroy foreign material

• phagocytic white blood cells

• can be distinguished by their 3-5 lobed nuclei

• 1.5x the size of red blood cells

eosinophil

• two-lobed nucleus

• red-orange granules in their cytoplasm

• 2x size of red blood cells

basophils

• rare

• granules stain very dark

• nucleus cant be seen because granules so dark

• nucleus indistinct and two lobed

• 2x size of red blood cells

• contain histamines (vasodilators) and heparin (anticoagulant that allows for movement of other white blood cells out of their capillaries to infection sites)

agranulocytes

nuclei not lobed, but may be dented or kidney bean shaped

• lymphocytes or monocytes

lymphocytes

have large, unlobed nucleus that usually has a flattened or dented area

• clear cytoplasm

• may appear as a blue halo around the purple nucleus

• separate cells have specific antibodies for specific antigens: B cells and T cells

• arise from fetal bone marrow

b cells versus t cells

b cells

• mature in the fetal liver and spleen

• mature into plasma cells, which make antibodies called immunoglobulins

• provide antibody-mediated immunity; that is, the plasma cells secrete antibodies that travel in the fluid portion of the blood

t cells

• mature in the thymus

• provide cell-mediated immunity

• cells themselves move close to and destroy bacteria or virus infected cells

• attack tumors and transplanted tissue

• most found in lymph nodes, thymus, and spleen

• enter bloodstream via lymphatics

monocytes

• very large and have a kidney bean shape

• 3x size of red blood cell

• activated by T cells

overall look at white blood cells

neutrophils

• represent about 60-70% of all white blood cells

• numbers increase in cases of appendicitis or acute bacterial infection

eosinophils

• represent about 2-4% of all WBCs

• increase in number during allergic reactions and parasitic infections

basophils

• represent about 0.5-1% of all WBCs

• increase in number during allergic and inflammatory reactions

lymphocytes

• make up about 20-25% of all WBCs

• numbers increase in cases of bacterial infection and antibody-antigen reactions

monocytes

• make up about 3-8% of WBCs

• numbers increase during chronic infections, such as tuberculosis

why do erythrocytes have a biconcave shape?

increases surface area and provides for greater oxygen-carrying abilities

what is blood formation called?

hematopoiesis or hemopoiesis

Formed elements consist of three main components: what are they?

red blood cells (erythrocytes), white blood cells (leukocytes)m and platelets (thrombocytes)

What is the most common plasma protein?

albumin

What is another name for a thrombocyte?

platelet

Which is the most common blood cell?

red blood cells

What is another name for a white blood cell?

leukocyte

Which white blood cell is the most numerous in a normal blood smear?

neutrophil

How many red blood cells are normally found per cubic millimeter of blood

5 million

What is an average number of white blood cells found per cubic millimeter

7,000

B cells and T cells belong to which class of agranular leukocytes

lymphocytes

What value is there to a change in the percentage of white blood cells to diagnostic medicine?

indicate diseases

In counting 100 WBC you are able to distinguish 15 basophils. Is this a normal number for the WBC count and what health issues can you draw from this?

not normal number, number is too high. Normal basophil count is 0.5%-1%. May indicate allergic reaction or exposure to radiation

What is the function of platelets?

aid in clotting

Formed elements constitute what percentage of the total blood volume?

45%

In terms of volume, does the blood normally contain more plasma or more formed elements?

plasma

A patient has a lymphocyte count of 42% of the total white blood cell count, What might be the clinical reason for this?

bacterial infection