Anatomy II - Exam I Flashcards
1
Q
What is blood?
A
fluid connective tissue
2
Q
Blood Composition
A
fluid connective tissue
plasma
formed elements
3
Q
Plasma
A
non living fluid matrix
4
Q
Formed elements
A
living blood cells suspended in plasma
5
Q
What are the formed elements?
A
erythrocytes
leukocytes
platelets
6
Q
Erythrocytes
A
red blood cells
no nuclei or organelles
7
Q
Leukocytes
A
white blood cells
complete cells
8
Q
Platelets
A
thrombocytes
cell fragments
9
Q
What is hematocrit?
A
percent of blood volume that is RBCs
10
Q
Functions of blood
A
Transport= oxygen and nutrients, wastes, hormones
Regulation= temperature and pH
Protection = clot formation and immune system
11
Q
Plasma Proteins
A
Albumins
Globulins
Fibrinogen
Transferrin
12
Q
Source and function of Albumins
A
Liver
Colloid osmotic pressure of plasma
carriers for various substances
13
Q
Source and function of Globulins
A
Liver and lymphoid tissue
Clotting factors, enzymes, antibodies, carriers for various substances
14
Q
Source and function of Fribrinogen
A
Liver
Forms fibrin threads essential to blood clottting
15
Q
Source and function of Transferrin
A
Lover and other tissues
Ion transport
16
Q
Structure of Erythrocytes
A
Biconcave discs
lots of hemoglobin
flexible to fit through narrow capillaries
17
Q
Function of Erythrocytes
A
respiratory gas transport
hemoglobin for gas transport
18
Q
Hemoglobin Structure
A
Globin- 4 polypeptide chains
Heme- pigment bonded to each globin chain, central iron atom binds one O2,
19
Q
Each Hb molecule can transport
A
four O2
20
Q
Hb reversibly binds
A
O2 and CO2 to a lesser extent
21
Q
Describe Hematopoietic stem cells
A
Give rise to all formed elements
Hormones and growth factors push cell toward specific pathway of blood cell development
Committed cells cannot change
22
Q
New blood cells enter
A
blood sinusoids
23
Q
What is Erythropoiesis
and
Describe the process
A
Red Blood Cell Production
HSC transforms into proerythroblast
Ribosomes synthesized
Hemoglobin synthesized; iron accumulates
Ejection of nucleus; formation of reticulocyte (young RBC)
24
Q
HSC transforms into what?/
A
pro erythroblast
25
A young RBC
reticulocyte
26
Balance between RBC production and destruction depends on?
- Hormonal controls
-Erythropoietin (EPO): Released by kidneys (some from liver) in response to hypoxia
Rapid maturation of committed marrow cells
Abused by endurance athletes; banned by WADA
-Adequate supplies of iron, amino acids, and B vitamins required
27
What are the causes of hypoxia?
- Decreased RBC numbers due to hemorrhage or increased destruction
- Insufficient hemoglobin per RBC (e.g., iron deficiency)
- Reduced availability of O2 (e.g., high altitudes)
28
What is the life span of Erythrocytes?
100-120 days
29
Describe the destruction of erthrocytes?
Life Span
Macrophages engulf dying RBS in spleen
Heme and globin are separated
30
Described what happens when heme and globin are separated
Iron: - Stored in cells as ferritin and hemosiderin
Transported in blood bound to the protein transferrin
Heme: degraded to yellow pigment bilirubin
Liver secretes bilirubin (in bile) into intestines
Degraded to pigment urobilinogen
Excreted as stercobilin
Globin: metabolized into amino acids - Released into circulation
31
What are the Erythrocyte Disorders?
Anemia
32
Anemia
decreased RBCs or hemoglobin
Blood has abnormally low O2-carrying capacity
Blood O2 levels cannot support normal metabolism
33
The three causes/types of Anemia
Blood loss
Low RBC production
High RBC destruction
34
Blood Loss : Anemia Cause
1. Hemorrhagic anemia
Rapid blood loss (e.g., stab wound)
Treated by blood transfusion
2. Chronic hemorrhagic anemia
Slight but persistent blood loss
Hemorrhoids, bleeding ulcer
Primary problem treated
35
Low RBC Production
1. Iron-deficiency anemia
Caused by hemorrhagic anemia, low iron intake, or impaired absorption
2 .Pernicious anemia
Autoimmune disease - destroys stomach mucosa – unable to absorb Vitamin B12
Vegetarians – low B12 in diet
3. Renal anemia
Lack of EPO – kidney disease
4. Aplastic anemia
Destruction or inhibition of red marrow by drugs, chemicals, radiation, viruses
36
High RBC Destruction
1. Hemolytic anemias
Premature RBC lysis due to: Hb abnormalities, incompatible transfusions or infections
2. Thalassemias
One globin chain absent or faulty
Found in people of Mediterranean ancestry
3. Sickle-cell anemia
Genetic disease resulting in one amino acid wrong in a globin beta chain
37
Describe Sickle Cell Anemia
Emerged in people of Sub-Saharan Africa and their descendants
1. Malaria kills 1 million each year
2. Sickle-cell gene
One copy Sickle-cell trait; milder disease; better chance to survive malaria
Two copies Sickle-cell anemia
Many RBCs are crescent shaped (and spikey, as you will see in the lab), rupture easily
Poor O2 delivery; pain
38
Function of Leukocytes
Function in defense against disease
Can leave capillaries via diapedesis
Move through tissue spaces by ameboid motion and positive chemotaxis
39
Types of Leukocytes
Granulocytes and Agranulocytes
40
Granulocytes
Visible cytoplasmic granules
| Neutrophils, eosinophils, basophils
41
Agranulocytes
No visible cytoplasmic granules
Lymphocytes, monocytes
Decreasing abundance in blood
Never let monkeys eat bananas
42
Types of Granulocytes
Neutrophils
Eosinophils
Basophils
43
Neutrophils
Most common WBCs
contain hydrolytic enzymes or defensins
3-6 lobes in nucleus; twice size of RBCs
Phagocytize bacteria
44
Eosinophils
Red/Orange-staining granules
Bilobed nucleus
Digest parasitic worms
Role in allergies, asthma and immune response
45
Basophils
Rarest WBCs with large purple granules
| Granules contain histamine - inflammatory chemical that acts as vasodilator
46
Types of Agranulocytes
Lymphocytes and Monocytes
47
Lymphocytes
2nd most common WBC
Large, dark-purple, circular nuclei with thin rim of blue cytoplasm
Mostly found in lymph nodes and spleen
Two types
T lymphocytes (T cells) act against virus-infected cells and tumor cells
B lymphocytes (B cells) give rise to plasma cells, which produce antibodies
48
Monocytes
Largest WBC
U- or kidney-shaped nuclei
Leave circulation, enter tissues, and differentiate into macrophages
Activate lymphocytes to mount an immune response
49
Leukopoiesis
Production of WBCs
Stimulated by 2 types of chemical messengers: Interleukins and
Colony-stimulating factors (CSFs)
50
Name the Leukocyte Disorders
Leukopenia
Leukemia – Cancer
Infectious Mononucleosis (Mono)
51
Infectious Mononucleosis (Mono)
Highly contagious viral disease caused by transmission of Epstein-Barr virus in saliva
52
overproduction of abnormal WBCs
Leukemia – Cancer
53
Abnormally low WBC count—drug induced
Leukopenia
54
Thrombocytes
Cytoplasmic fragments of megakaryocytes
Form temporary platelet plug that helps seal breaks in blood vessels
Formation regulated by thrombopoietin
Granules contain substances like platelet-derived growth factor (PDGF)
55
Hemostasis
Fast series of reactions for stoppage of bleeding
Requires clotting factors, and substances released by platelets and injured tissues
Three steps
Vascular spasm
Platelet plug formation
Coagulation (blood clotting)
56
What are the three phases of coagulation?
Prothrombin activator formed in both intrinsic and extrinsic pathways
Prothrombin converted to enzyme thrombin
Thrombin catalyzes fibrinogen fibrin
57
Describe Clot Retraction
Stabilizes clot
Actin and myosin in platelets contract
Contraction pulls on fibrin strands, squeezing serum from clot
Draws ruptured blood vessel edges together
58
Vessel Repair
Vessel is healing as clot retraction occurs
Platelet-derived growth factor (PDGF) stimulates division of smooth muscle cells and fibroblasts to rebuild blood vessel wall
Vascular endothelial growth factor (VEGF) stimulates endothelial cells to multiply and restore endothelial lining
Fibrinolysis
Removes unneeded clots after healing
59
What are the disorders of Hemostasis ?
Thromboembolic disorders: undesirable clot formation
Bleeding disorders: abnormalities that prevent normal clot formation
Disseminated intravascular coagulation (DIC)
Involves both types of disorders
60
What are the Thromboembolic Conditions?
Thrombus: clot that develops and persists in unbroken blood vessel
May block circulation leading to tissue death
Embolus: thrombus freely floating in bloodstream
Embolism: embolus obstructing a vessel
E.g., pulmonary and cerebral emboli
Risk factors – atherosclerosis*, inflammation, slowly flowing blood or blood stasis from immobility
61
What are the Anticoagulant Drugs?
Aspirin
Antiprostaglandin that inhibits thromboxane A2
Heparin
Anticoagulant used clinically for pre- and postoperative cardiac care
Warfarin
Used for those prone to atrial fibrillation
Interferes with action of vitamin K
Dabigatran directly inhibits thrombin
62
Hemophilia
```
Includes several similar hereditary bleeding disorders affecting different clotting factors
Hemophilia A(most common), B and C
```
Symptoms include prolonged bleeding, especially into joint cavities
Treated with plasma transfusions and injection of missing factors
Increased hepatitis and HIV risk
63
Disseminated Intravascular Coagulation
Clotting causes bleeding
Widespread clotting blocks intact blood vessels
Severe bleeding occurs because residual blood unable to clot
Occurs as pregnancy complication; in septicemia, or incompatible blood transfusions
64
Transfusions
Whole-blood transfusions used when blood loss rapid and substantial
Packed red cells (plasma and WBCs removed) transfused to restore oxygen-carrying capacity
Transfusion of incompatible blood can be fatal
65
Human Blood Groups Important Terms
Agglutination – clumping together of RBC
Agglutinogens – Antigens or surface markers on RBC cell membrane that are bound by antibodies
Agglutinins – Antibodies that recognize and bind the antigens and cause agglutination
66
Human Blood Groups
RBC membranes possess surface glycoprotein antigens
Anything perceived as foreign; generates an immune response
agglutinogens
Mismatched transfused blood (e.g. type A blood given to person with type B) perceived as foreign
May be agglutinated and destroyed; can be fatal
Presence or absence of each antigen is used to classify blood cells into different groups
Antigens of ABO and Rhesus blood groups cause vigorous transfusion reactions
67
Type A Group
has only A agglutinogens
| and Anti-B agglutinins – will agglutinate B or AB blood cells
68
Type B Group
Has only B agglutinogens
| and Anti-A agglutinins – will agglutinate A or AB blood cells
69
Type AB Group
Universal Recipient
| Has A and B agglutinogens
70
Type O
Universal Donor
Has no A or B agglutinogens – won’t be agglutinated by recipient
and A and B agglutinins
Universal Donor
Has no A or B agglutinogens – won’t be agglutinated by recipient
and A and B agglutinins
71
Rh Blood Groups
Rh+ indicates presence of D antigen
85% Americans Rh+
Anti-Rh antibodies(agglutinins) are not spontaneously formed in Rh– individuals
Anti-Rh antibodies form if Rh– individual receives Rh+ blood, or Rh– mother carries a Rh+ fetus
Second exposure to Rh+ blood will result in typical transfusion reaction
72
Homeostatic Imbalance: Hemolytic Disease of the Newborn
Also called erythroblastosis fetalis
Only occurs in Rh– mom with Rh+ fetus
Rh– mom exposed to Rh+ blood of fetus during delivery of first baby – baby healthy
Mother synthesizes anti-Rh antibodies
Second pregnancy
Mom's anti-Rh antibodies cross placenta and destroy RBCs of Rh+ baby
Baby treated with prebirth transfusions and exchange transfusions after birth
RhoGAM serum containing anti-Rh can prevent Rh– mother from becoming sensitized
73
Transfusion Reactions
Occur if mismatched blood infused
Donor's cells
Attacked by recipient's plasma agglutinins
Agglutinate and clog small vessels
Rupture and release hemoglobin into bloodstream
Result in
Diminished oxygen-carrying capacity
Diminished blood flow beyond blocked vessels
Hemoglobin in kidney tubules renal failure
74
Before Transfusion
Blood typing
Mixing RBCs with antibodies against its agglutinogen(s) causes clumping of RBCs
Done for ABO and for Rh factor
Cross matching
Mix recipient's serum with donor RBCs
Mix recipient's RBCs with donor serum
To see if agglutination occur in both cases
