Set 6 (Part I) Flashcards
1
Q
What is the function of blood vessels?
A
Contain the blood
2
Q
Why do we need blood?
A
For the transport of gas, nutrients, waste, cytokines, clotting factors, hormones, etc.
3
Q
What is an angioplasty?
A
Opens blocked arteries and restores normal blood flow to your heart muscle
4
Q
What are the three types of proteins found in the blood?
A
- Albumins (58%)
- Globulins (38%)
- Fibrinogen (4%)
5
Q
What are the two major components of blood and what percentage do they form?
A
- Plasma (55%)
- Formed elements (45%)
6
Q
What are the components of plasma and their percentages?
A
- Proteins (6%)
- Water (92%)
- Other solutes (2%): ions, nutrients, waste products, gases
7
Q
What are the components of the buffy coat?
A
- Platelets
- Leukocytes
8
Q
What factors may alter the composition of blood?
A
- Disease
- Drug use
- Altitude
- Hormonal status
- Exercise status
9
Q
What is oncotic pressure?
A
Force that is pulling the fluid back in at the tissue level
10
Q
What plasma proteins does the liver produce?
A
- Albumins
- Globulins
- Fibrinogen
- Transferrin
11
Q
What other tissue (apart from the liver) produces globulins?
A
Lymphoid tissue
12
Q
What is the function of albumins?
A
- Major contributors to colloid osmotic pressure of plasma
- Carriers for various substances
13
Q
What is the function of globins?
A
- Clotting factors
- Enzymes
- Antibodies
- Carriers for various substances
14
Q
What is the function of fibrinogen?
A
Forms fibrin threads essential to blood clotting
15
Q
What is the function of transferrin?
A
Iron transport
16
Q
Why is osmotic pressure necessary?
A
- If all of the fluid gets filtered out, the tissues are going to be absolutely overloaded with fluid
- Thus, a driving force pulling the fluid back in is necessary
17
Q
What force pushes fluid out? What force pulls fluid in?
A
- Hydrostatic: pushes out
- Osmotic: pulls in
18
Q
How do albumins relate to osmotic pressure?
A
Plasma proteins, such as albumins, are a huge driving force to pull fluid back into the blood vessel
19
Q
What is the structure of RBCs? What creates this structure?
A
- Biconcave disk shape
- The cytoskeleton creates a unique shape
20
Q
What are the two functions of RBCs structure?
A
- Flexible to ease transportation
- Also, increases surface area to allow for maximum oxygen transport
21
Q
What cytoskeletal protein is partially responsible for the elastic strength under deformation of RBCs? What does it bind to?
A
- Spectrin
- Binds to the cytosolic side of the membrane protein
22
Q
What is the structure of each spectrin molecule?
A
Consists of two intertwined polypeptide chains
23
Q
What is the size of RBCs?
A
7.5 um
24
Q
Packed within each RBC are approximately how many molecules of hemoglobin?
A
200 to 300 million
25
What is hemoglobin composed of?
- Four protein chains (globins)
- Each globin has a heme group
- Each heme contains one iron
26
How many iron molecules are found per one molecule of hemoglobin?
4
27
What gives RBCs its red colour?
Heme/iron
28
Why can RBCs bind to carbon dioxide?
Globulin makes this reaction possible
29
What does hemoglobin synthesis require?
Iron
30
How long does the maturation process of RBCs take?
4 days
31
All blood cells are derived from what?
Hematopoietic stem cells (hemocytoblast)
32
What does differentiation of RBCs begin with?
The appearance of proerythroblasts
33
The mitotic divisions of proerythroblasts produce what?
Basophilic erythroblasts
34
What is created from basophilic erythroblasts?
Polychromatic erythroblasts, which produce hemoglobin
35
Are RBCs synthesized with nuclei, or without?
They are synthesized with nuclei, but lose their nuclei to become reticulocytes
36
How do RBCs mature following differentiation?
Once released into the blood within 24 to 36 hours
37
Where does erythropoiesis occur?
In the bone marrow
38
What are platelets? What do they arise from?
- They are not cells of their own, but cellular FRAGMENTS
| - They arise from the megakaryocyte
39
What do all of the formed elements arise from?
Stem cells, which mature upon entering circulation
40
What may negatively affect bone marrow function? Why?
- Bone marrow depression drugs
- Radiation therapy
- Since these therapies target DIVIDING cells, making stem cells susceptible
41
What is aplastic anemia?
Reduction in the production of RBCs
42
What is leukopenia? What is the major consequence?
- Reduction of WBCs
| - Leaves a person open to many infections
43
What is thrombocytopenia? What is the major consequence?
- Reduction in the production of platelets
| - Leaves a person at high risk for a hemorrhage
44
What is erythropoiesis?
Formation of red blood cells
45
How is erythropoiesis stimulated?
- In response to low oxygen levels, the kidneys release erythropoietin (glycoprotein)
- Stimulates bone marrow to accelerate its production of RBCs
46
Why would athletes train at higher altitudes?
- Less oxygen available, which stimulates erythropoiesis
| - More RBCs = more oxygen delivered to tissues
47
How long do RBCs last? What must occur afterwards?
- Live for around 120 days
| - Must be replaced and dismantled into components
48
What first occurs in the destruction of RBCs?
Macrophage cells in the liver and spleen phagocytose the aged, abnormal, or fragmented RBCs
49
What does the phagocytosis of RBCs result in?
The breakdown of hemoglobin, with the release of amino acids, iron, and bilirubin (excreted as bile)
50
What happens to iron from RBC destruction?
Returned to the bone marrow for synthesis of new hemoglobin
51
What happens to bilirubin from RBC destruction?
Transported to the liver, where it is excreted into the intestine as part of bile
52
What happens to amino acids from RBC destruction?
Used for energy or the synthesis of new proteins
53
What is iron transported by in the plasma?
Transferrin
54
What organ stores excess iron? As what?
- Liver
| - Ferritin
55
What is packed cell volume (PCV)?
The percent of RBC
56
What is the normal hematocrit for men and women?
- Men: 45% RBCs
| - Women: 42% RBCs
57
Differentiate anemia and polycythemia?
- Anemia: reduced PCV
| - Polycythemia: increased PCV
58
What percentage of the blood volume does WBCs and platelets make up?
1%
59
How do you recognize a neutrophil under a microscope?
Much larger than RBCs and have a multi-lobed nucleus
60
How do iron deficient RBCs compare to normal?
Iron deficient RBCs are not well filled with hemoglobin and are not uniform in size
61
What are the three granulocytes?
- Basophils
- Neutrophils
- Eosinophils
62
What is the difference between granulocytes and agranulocytes?
- Granulocytes have VISIBLE granules
| - Agranulocytes also have granules, but they're less visible
63
Which WBC makes up the largest portion of the leukocyte count?
Neutrophils (65%)
64
What is the function of neutrophils?
- Highly mobile
- Very active phagocytic cells
- Capable of diapedesis
- Contain lysosomes
65
Which cells are capable of diapedesis? What is it?
- Neutrophils and basophils
| - Migrate out of the blood vessel and enter tissues
66
What are lysosomes important for?
Destruction of bacterial cells
67
Where are eosinophils largely found?
Numerous in lining of respiratory and digestive tracks
68
Which granulocyte is a weak phagocyte?
Eosinophils
69
What are the functions of eosinophils?
- Provide protection against infections caused by parasitic worms
- Release inflammatory substances in allergic reactions
70
What are the functions of basophils?
- Motile and capable of diapedesis
| - Granules contain histamine (inflammatory) and heparin (anticoagulant)
71
What are the two agranulocytes?
- Lymphocytes
| - Monocytes
72
Lymphocytes have little _______.
cytoplasm
73
Which WBC type is the smallest?
Lymphocytes
74
Where are B-cells and T-cells produced and mature?
- B-cells are produced and mature in the bone marrow
| - T-cells are produced in the bone marrow, but mature in the thymus
75
What are the three types of lymphocytes?
- T-cells
- B-cells
- NK cells
76
What is the primary function of T-cells?
Directly attack an infected or cancerous cell
77
What is the primary function of B-cells?
Produce antibodies against specific antigens
78
Which WBC is the largest?
Monocytes
79
What are the functions of monocytes? What are they?
- Mobile and highly phagocytic
- Ingests bacteria and cancerous cells
- Monocytes are the inactive form of macrophages, which mature once they arrive to their tissues
80
What are platelets also called?
Thrombocytes
81
What do platelets look like in circulation?
Small, pale bodies that appear as irregular spindles or oval disks
82
What are the three important properties of platelets?
- Agglutination
- Adhesiveness
- Aggregation
83
What are the two major functions of platelets?
- Hemostasis
| - Blood coagulation
84
What is hemostasis?
Stoppage of blood flow
85
How does blood-clotting relate to hemostasis?
If the injury is extensive, blood-clotting mechanism is activated to assist hemostasis
86
What are megakaryocytes?
- Giant cells with multiple copies of DNA in the nucleus
| - The edges break off to form cell fragments (platelets)
87
Describe platelet plug formation.
1. Exposed collagen binds and activates platelets
2. Release of platelet factors
3. Factors attract more platelets (positive feedback)
4. Platelets aggregate into a platelet plug
88
What is the first thing that occurs when there is damage to a tissue?
Vasospasm (vasoconstriction) reduces the diameter of the blood vessel
89
Describe the blood-clotting mechanism.
1. Release of clotting factors from both injured tissue cells and sticky platelets at the injury site (temporary platelet plug)
2. Formation of thrombin
3. Formation of fibrin, which raps blood cells to form a clot
90
What is responsible for converting fibrinogen to fibrin?
Thrombin
91
Which mineral is required for blood clotting mechanisms?
Calcium
92
What is temporary hemostasis?
Platelets aggregate into loose platelet plug
93
What is the ABO system based on?
Named according to cell-surface antigens present on RBC membranes
94
Which RBC antigens does type O contain? Which antibodies?What can it receive? What can it donate?
- Antigens: none
- Antibodies: anti-A and anti-B
- Universal donor
- Can only receive from O
95
Which RBC antigens does type A contain? Which antibodies? What can it receive? What can it donate?
- Antigen: A
- Antibody: anti-B
- Receives from O or A
- Can donate to type A or AB
96
Which RBC antigens does type B contain? Which antibodies? What can it receive? What can it donate?
- Antigen: B
- Antibody: anti-A
- Receives from O or B
- Can donate to type B or AB
97
Which RBC antigens does type AB contain? Which antibodies? What can it receive? What can it donate?
- Antigens: A and B
- Antibody: none
- Universal recipient
- Can only donate to AB
98
What is the universal donor (including Rh system)?
O negative
99
What is the universal acceptor (including Rh system)?
AB positive
100
What does the term Rh-positive blood mean?
Rh antigen is present on RBCs
101
When are anti-Rh antibodies solicited?
- They are NOT normally present in the blood
| - Appear in Rh-negative blood only if it has come in contact with Rh-positive RBCs
102
How may Rh-negative blood come in contact with Rh-positive RBCs?
- Transfusion
| - Pregnancy
103
What explains hemolytic disease of a newborn?
- Rh negative women has Rh positive fetus (second pregnancy)
- If not treated, the Rh positive blood cells enter the mother's bloodstream at delivery
- If not treated, the mother's body will produce anti-Rh
- Anti-Rh causes agglutination of RBCs in the fetus (fatal)
104
How do you prevent a Rh negative mother from hemolytic disease of a newborn?
Suppressive drug RhoGAM, which stops mother's body from making antibodies to Rh
105
```
Which group of leukocytes is the most common in a blood sample from a healthy human?
A) Neutrophils
B) Monocytes
C) Lymphocytes
D) Eosinophils
E) Basophils
```
A) Neutrophils
106
```
Which blood components have no nucleus?
A) Macrophages
B) Red blood cells
C) Platelets
D) Two of the above
E) All of the above
```
D) Platelets and RBCs
107
```
The percentage of the volume of whole blood occupied by RBCs is called the _____.
A) Differential
B) Hematocrit
C) Packed cell volume
D) Mean corpuscular volume
```
B) Hematocrit
| C) Packed cell volume
108
```
Normally, whole blood is about ___% cells and ____% plasma.
A) 25; 75
B) 30; 70
C) 45; 55
D) 60; 40
E) 65; 35
```
C) 45; 55
109
```
The end product of the coagulation cascade is _____.
A) Activated platelets
B) Repair of the blood vessel wall
C) Fibrin polymers
D) Thrombin
E) Heparin
```
C) Fibrin polymers
110
```
Which of the following is NOT a protein?
A) Prostacyclin
B) Plasmin
C) Plasminogen
D) Fibrin
```
A) Prostacyclin
111
```
Blood cells are produced in the ______.
A) Spleen
B) Liver
C) Bone marrow
D) Kidneys
E) Vascular epithelium of blood vessels
```
C) Bone marrow
112
```
The term for the production of blood cells is _____.
A) Hemostasis
B) Hemorrhage
C) Coagulation
D) Erythropoiesis
E) Hematopoiesis
```
E) Hematopoiesis
113
```
A pluripotent hematopoietic stem cell can generate any of the following cell types EXCEPT _______.
A) Erythrocyte
B) Reticulocyte
C) Fibroblast
D) Basophil
E) Neutrophil
```
C) Fibroblast
114
```
An athlete using EPO (erythropoietin) is hoping to generate an increase in ______.
A) RBCs
B) WBCs
C) Platelets
D) Blood volume
E) Blood pressure
```
A) RBCs
115
How does plasma differ from interstitial fluid?
The presence of plasma proteins
116
How does the osmotic pressure of blood compare to that of interstitial fluid?
- Osmotic pressure of the blood is higher than interstitial fluid
- Due to the presence of plasma proteins in the blood
117
Are platelets nucleated or enucleated?
They are enucleated cell fragments that split off from a megakaryocyte
118
What are tissue basophils called?
Mast cells
119
What are tissue monocytes called?
Macrophages
120
Why do we say that erythrocytes and platelets are not fully functional cells?
Because they lack a nucleus, which means that they cannot carry-out protein synthesis
121
Explain why patients with liver degeneration frequently suffer from edema.
- Liver degeneration reduces the total plasma protein concentrations
- Reduces the osmotic pressure in the capillaries
- Decrease in osmotic pressure increases net capillary filtration
- Results in edema
122
What is the precursor of all blood cells?
Pluripotent hematopoietic stem cell (bone marrow)
123
What does thrombopoietin influence? Where is it produced?
- Primarily produced in the liver
| - Influences growth/differentiation of megakaryocytes
124
What does hypoxia (low oxygen levels in tissues) stimulate?
- The synthesis and release of erythropoietin
| - EPO stimulates the synthesis of RBCs, which puts more hemoglobin into the circulation to carry oxygen
125
Why is EPO technically a cytokine, and not a hormone?
Because it is made on demand, and not stored in vesicles
126
What is the primary source of ATP of RBCs? Why?
- Glycolysis
| - Because they contain no mitochondria
127
What makes older RBCs more fragile?
- They do not contain a nucleus or an ER to carry out protein synthesis
- They cannot renew membrane components or enzymes
128
RBCs live about ____ days in the blood.
120 days
129
What is the function of the spleen in terms of RBCs?
Destroys old RBCs and converts hemoglobin to bilirubin
130
What contributes to the yellow color of urine?
Bilirubin
131
What causes jaundice?
Accumulation of bilirubin levels in the blood
132
Distinguish between heme and hemoglobin.
Heme is an iron-containing subunit of a hemoglobin molecule
133
Distinguish between ferritin and transferrin.
- Ferritin is the liver protein that stores iron
| - Transferrin is the plasma protein that transports iron in the blood
134
Is bile an endocrine secretion or an exocrine secretion?
Bile is an exocrine secretion because it is secreted into the intestine
135
What is anemia?
- Hemoglobin content is too low
| - The blood cannot transport oxygen to the tissues
136
What clinical markers do individuals with iron-deficiency anemia have?
- Low red blood cell count (low hematocrit)
- Or, low hemoglobin content in their blood
- Microcytic and hypochromic cells
137
How could diarrhea cause a temporarily elevated hematocrit?
- Diarrhea causes dehydration, which is a loss of fluid volume
- If plasma volume decreases (and RBC is unchanged), the hematocrit increases
138
What does the cytoplasm of platelets contain?
- Mitochondria
- Smooth ER
- Numerous granules that are filled with cytokines and growth factors
139
What is the typical life span of platelets?
10 days
140
Define hemostasis.
The process of keeping blood within a damaged blood vessel
141
What are the three major steps of hemostasis?
1) Vasoconstriction
2) Temporary blockage of a break by a platelet plug
3) Coagulation (formation of a clot that seals the hole)
142
What activates platelets when a blood vessel wall is first damaged?
Exposed collagen and chemicals from endothelial cells
143
How do platelets adhere to collagen?
With the help of integrins
144
What prevents the platelet plug from continuing to form and spread beyond the site of injury to other areas of the vessel wall?
- Platelets do not adhere to normal endothelium
- Intact vascular endothelial cells convert their membrane lipids into prostacyclin, which blocks platelet adhesion and aggregation
145
What two mechanisms limit the extent of blood clotting within a vessel?
1) Inhibition of platelet adhesion
| 2) Inhibition of the coagulation cascade and fibrin production
146
The enzyme plasmin __________.
A) can damage blood vessels by eroding endothelial cells
B) produces fibrin
C) is trapped within the platelet plug as it is formed
D) is trapped within the platelet plug as it is formed, causing fibrinolysis, thereby slowly dissolving the clot
D) is trapped within the platelet plug as it is formed, causing fibrinolysis, thereby slowly dissolving the clot
147
What prevents platelet adhesion in intact endothelium?
The release of prostacyclin and nitric oxide
148
The coagulation pathway that is initiated with the appearance of tissue factor is the __________ pathway.
A) thrombin
B) common
C) intrinsic
D) extrinsic
D) extrinsic
