AP 2 Quiz 1

Plasma

A clear, light-yellow fluid constituting a little over half of the blood volume

Thrombopoiesis vs Thrombocytopenia

Thrombopoiesis: The process of platelet (thrombocyte) production from megakaryocytes in the bone marrow

Thrombocytopenia: A condition characterized by abnormally low platelet count in the blood

What is PDGF?

PDGF is a growth factor from platelets that stimulates fibroblasts and smooth muscle cells to repair damaged vessels after clotting

Difference between neutropenia, neutrophilia and leukopenia, leukemia

Neutropenia: WBC deficiency (low neutrophils)

Neutrophilia: WBC excess (high neutrophils)

Leukopenia: General low WBC count

Leukemia: High WBC count - Cancer of WBC-forming stem cells

WBC life history

• Born: red bone marrow

• Mature: marrow / thymus (T cells)

• Die: tissues or lymphatic organs

How many polypeptides make up hemoglobin?

4:

• 2 alpha chains

• 2 beta chains

RBC life history

• Made: red bone marrow

• Lifespan: ~120 days

• Destroyed: spleen & liver

• Iron recycled

• Heme → bilirubin → bile

What is the most common vs most rare WBC?

Common: Neutrophil

Rare: Basophil

In Kwashiorkor, low albumin =

Low albumin production by the liver results in hypoproteinemia

What happens to the water in a person with Kwashiorkor?

• Reduced plasma proteins → ↓ blood osmotic pressure

• Water moves out of blood vessels

• Fluid accumulates in:

  • Interstitial spaces (edema)

  • Abdominal cavity (ascites)

• Produces the characteristic swollen belly despite malnutrition

What is ascites?

Abnormal accumulation of fluid in the abdominal cavity

• occurs when plasma osmotic pressure is too low to retain water in blood vessels

What happens if blood osmolarity drops?

Water moves out of the blood into surrounding tissues

Explain the significance of blood viscosity. How does viscosity relate to flow?

Blood viscosity = thickness of blood

• High viscosity = low flow = high workload on heart = high RBC

What is thrombosis?

Formation of a blood clot (thrombus) in an unbroken blood vessel

• blocks blood flow, can cause ischemia and tissue damage

What is embolus?

A detached thrombus or other material traveling through the bloodstream

• lodges in smaller vessels, can cause stroke, pulmonary embolism, or heart attack

Erythrocytes

Red blood cells which are the heaviest components and settle first

Leukocytes

White blood cells and platelets that make up 1% total volume and buffy coat

In a centrifuged blood sample, how does RBC, WBC, and plasma sit?

RBC is heaviest so it is on the bottom

Buffy coat: leukocytes and platelets

Plasma (55% of whole blood)

Function of lymphocytes

destroy cells (cancer, foreign, and virally infected cells)

Present antigens to activate other immune cells

Coordinate actions of other immune cells

Secrete antibodies and provide immune memory

What is plasma made up of?

Complex mixture of water, proteins, nutrients, electrolytes, nitrogenous wastes, hormones, and gases

How many L of blood does a human hold?

5.5L

Blood plasma vs Blood serum?

Plasma is the liquid, cell-free part of the blood, that has been treated with anti-coagulants

Serum is the liquid part of blood after coagulation, therefore lacking clotting factors as fibrinogen

• plasma - fibrinogen = serum

What is blood plasma made up of?

Proteins such as albumin and fibrinogen

Electrolytes such as sodium, potassium, and calcium

Nutrients

Hormones and waste products

Dissolved O2, CO2, and nitrogen

Albumin and fibrinogen help maintain?

Osmotic pressure and blood clotting

Leukocytes are broken into what two groups?

Granulocytes and Agranulocytes

Granulocytes make up?

Neutrophils

Eosinophils

Basophils

Agranulocytes make up?

Lymphocytes

Monocytes

What are the formed elements?

• Erythrocytes

• Leukocytes

  • Granulocytes

    • neutrophils

    • Eosinophils

    • Basophils

  • Agranulocytes

    • Lymphocytes

    • Monocytes

• Platelets

Hematocrit

The percentage of blood volume that is composed of erythrocytes

WBCs and platelets settle into a?

Narrow cream- or buff-colored zone called the buffy coat

If plasma is separated, allowed to coagulate (clot), and centrifuged again, the clotting proteins (mainly fibrin) settle to the bottom of the tube and the overlying fluid is called?

Blood serum

Functions of albumin

• Osmotic pressure

• Blood viscosity

• Transports lipids, hormones, calcium, and other solutes

• Buffers blood pH

• Blood pressure

• Flow and balance

Functions of globulins

Transport and defense functions as itemized below

Functions of fibrinogen

• Becomes fibrin

• The major component of blood clots

What is albumin?

Maintains blood osmotic pressure, keeps water inside blood vessels, prevents edema and fluid loss into tissues

• Smallest and most abundant plasma protein in the liver

What are the three subclasses of globulins? What do they do?

Smallest to largest in MW:

• Alpha (a) - transport proteins

• Beta (B) - transport proteins

• Gamma (y) - clotting protein

What are globulins?

Antibodies that provide immune system functions

What is fibrinogen?

Precursor of fibrin threads that help form blood clots

What is plasminogen?

Precursor to plasma which dissolves blood clots

Plasma proteins are formed by the?

Liver

Globulins are formed by?

Produced by plasma cells, a type B lymphocyte

Kwashiorkor is?

A disease marked by severe protein malnutrition and bilateral extremity swelling.

• affects infants and children

• severe cases of starvation and poverty-stricken regions

What is the most abundant nitrogenous waste?

Urea, a product of amino acid catabolism

What is Hypoproteinemia

Condition where the total protein levels in the blood fall below the normal range

• can cause edema in the abdomen

Osmosis

A process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane.

Label the erythrocytes, neutrophils, and platelets:

The biggest component of blood in terms of volume is?

Plasma

What are platelets?

Cell fragments from special cell (megakaryocyte) in bone marrow

What are the stained colors of the 3 granulocytes?

• Basophils (stained blue/purple)

• Eosinophils (stained red/pink/orange)

• Neutrophils (neutral balance of colors above)

What are the stained colors of the agranulocytes?

• Lymphocytes  (B & T cells)

• Monocytes 

Function of erythrocytes?

Transport O2 and CO2 (mainly O2)

Function of neutrophils

Phagocytes that engulf bacteria and debris

Function of eosinophils

Attack parasitic worms; important in allergic reactions

Function of basophils

Release histamine, which is important in allergic reactions, and heparin, which helps clear fat from the blood

Function of monocytes

Leave bloodstream and transform into macrophages

• Phagocytize pathogens and debris

• Present antigens to activate other immune cells

The first hematopoietic tissues of the human embryo form in the?

Yolk sac, a membrane associated with all vertebrate embryos

Hemoglobin

The red gas transport pigment of an erythrocyte

Function of B and T lymphocytes

B lymphocytes: produce antibodies

T lymphocytes: cell-mediated immune responses

Function of platelets

Homeostasis

Blood formation in the bone marrow and lymphoid organs is called?

myeloid and lymphoid hematopoiesis

What are the characteristics of RBC’s?

• Disc-shaped cell with thick rim

• 7.5 um diameter and 2.0 um thick at rim

• lose nearly all organelles during development

  • anaerobic fermentation to produce ATP

• lack nucleus and DNA

  • no protein synthesis or mitosis

Erythropoiesis

The production of erythrocytes

How does erythropoiesis begin?

When a hematopoietic stem cell (HSC) becomes an erythrocyte colony-forming unit (CFU)

Erythropoietin

A hormone that is secreted by the kidneys and liver in response to hypoxemia and stimulates erythropoiesis

Hypoxemia

A deficiency of oxygen in the bloodstream

When hypoxemia occurs, what do the kidneys do?

The kidneys detect this and increase their EPO output. 3-4 days later, the RBC count begins to rise and reverse the hypoxemia

Hemopoietic tissues produce?

Blood cells

When does the liver stop producing blood cells?

At birth

Yolk sac (of the embryo) produces?

Stem cells for the first blood cells

What stimulates more RBC production?

EPO = Erythropoietin

Primary polycythemia (polycythemia vera) is?

An RBC excess due to cancer of the erythropoietic line of the red bone marrow

• RBC count can be as high as 11 million RBCs/uL

• Hematocrit as high as 80%

Secondary polycythemia is

RBC counts as high as 11 million RBCs/uL due to dehydration, emphysema, high altitude, or physical conditioning

Relative polycythemia

RBC count up to 8 million RBCs/uL due to low plasma volume

Dangers of polycythemia

Increases blood volume, pressure, viscosity

• can lead to embolism, stroke, or heart failure

Causes of anemia fall into 3 categories, they are?

1. Inadequate erythropoiesis or hemoglobin synthesis

2. Hemorrhagic anemia from bleeding

3. Hemolytic anemia from RBC destruction

What are examples of inadequate erythropoiesis or hemoglobin synthesis

• Kidney failure & insufficient erythropoietin

• Iron-deficiency anemia

• Pernicious anemia

• Hypoplastic anemia

• Aplastic anemia

• Porphyria

Porphyria

Lack enzymes to synthesize heme

Aplastic anemia

Complete cessation of erythropoiesis and all other blood cells (WBCs & platelets)

Hypoplastic anemia

Slowing of erythropoiesis

Pernicious anemia

Autoimmune attack of stomach tissue leads to inadequate vitamin B12 absorption

What is anemia caused by?

Too few RBCs or low Hb

What are the 3 consequences of anemia?

1. Tissue hypoxia and necrosis

2. Blood osmolarity is reduced, producing tissue edema

3. Blood viscosity is low

What is sickle-cell?

A hereditary hemoglobin defect found mostly among people of sub-Saharan Africa, the Mediterranean basin, the Middle East, and India.

• Caused by recessive alleles that modifies structure of Hb (makes HbS)

What causes the pain in sickle-cell patients?

HbS does not bind O2 well, erythrocytes are sticky; they agglutinate and block small blood vessels, causing intense pain in oxygen-starved tissues

What can sickled cell lead to? What advantage does it have?

Kidney or heart failure, stroke, joint pain, or paralysis

Heterozygote “advantage” are resistant to malaria

What is the heme group?

The heme group consists of a porphyrin ring with an iron (Fe2+) ion at its center

• allows it to bind oxygen molecules reversibly

• 4 total heme groups for each polypeptide

The antibody that reacts against antigen B is

Beta agglutinin or anti-B

The antibody that reacts against antigen A is

Alpha agglutinin or anti-A

A person who is type A is?

Anti-B, so should never get type B or AB transfusion

A person with a type B is

Anti-A, so should never get type A or AB blood

Type O is?

Anti-A and Anti-B, so they cannot safely receive type A, B, or AB blood

Those who have genotype DD or Dd (D antigen) are? Those who do not have it?

Rh+

Rh-

Agglutinogen vs Agglutinin

Agglutinogen: Specific antigens found on the surface of cells, such as red blood cells. They stimulate an immune response when recognized as foreign by the body

• they determine blood groups

• called Antigen A and B

Agglutinin: These are antibodies produced by the immune system in response to agglutinogens. They bind to corresponding agglutinogens, leading to agglutination, which is the clumping of cells

• found in plasma

• Anti-A and anti-B

Universal donor is?

Type O: most common bloody type

• lacks RBC antigens

• Donor’s plasma may have both antibodies against recipient’s RBC’s

• May give packed cells

Universal recipient is?

Type AB: rarest blood type

• lacks plasma antibodies; no anti-A or anti-B

What is hemolytic disease of the newborn (HDN)?

Can occur if Rh- mother has formed antibodies and is pregnant with second Rh+ child

• anti-D antibodies can cross placenta and attack fetal blood causing severe anemia and toxic brain syndrome

What are the preventions for HDN?

RhoGAM, given to pregnant Rh- women to bind fetal agglutinogens in her blood so she will not form anti-D antibodies

Anti-D agglutinin are present when?

Forms in Rh- individuals exposed to Rh+ blood

What is the relative abundance of WBCs?

Most abundant to least abundant

1. Neutrophils

2. Lymphocytes

3. Monocytes

4. Eosinophils

5. Basophils

Hemostasis

The stopping of blood flow from a damaged blood vessel