Cardiovascular System Flashcards

1
Q

WHole blood is a…

A

…liquid connective tissue

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2
Q

Whole blood makes up…

A

…8% of total body weight

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3
Q

55% of whole blood is made up of…

A

…blood plasma

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4
Q

45% of whole blood is made up of …

A

…formed elements

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5
Q

Temperature of whole blood?

A

38 deg celcius

(1oC higher than oral/rectal body temp)

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6
Q

WHole blood is 5 times as viscous as…

A

…water

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7
Q

WHole blood is slightly…

A

…alkaline

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8
Q

Whole blood has three general functions which are…

A

Transportation
Regulation
protection

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9
Q

Physiology of Blood:

A
  • Blood components
  • Plasma
    – plasma constituents
  • Platelets
    – blood coagulation and platelets
  • White cells
    – white cell types and functions
  • Red cells
    – haemoglobin and oxygen transport
    – red cells and respiratory gas transport
    – red cell adaptations to function
  • Major blood disorders
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10
Q

Plasma constituents:

A

Proteins (7%)
Solutes (2%)
-inorganic ions (1%)
-organic compounds and others (1%)

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11
Q

Whats the main protein found in plasma?

A

Albumin (60%)

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12
Q

Albumin regulates…

A

…colloidal osmotic pressure

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13
Q

Albumin maintains…

A

…blood viscosity / volume

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14
Q

Albumin is a protein…

A

….reserve in malnutriton

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15
Q

Transports of albumin?

A

long-chain fatty acids, sterols, bilirubin

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16
Q

What does Albumin do to drugs?

A
  • Binds and solubilises drugs
  • Binds Ca2+
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17
Q

Proteins found in plasma?

A

α & β globulins (~30%)
γ globulins (~5%)
Fibrinogen, prothrombin (~5%)

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18
Q

What comes under inorganic ions?

A
  • Osmotic pressure
  • pH (H+), Na+, K+, Cl-, HCO3-
  • Ca2+
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19
Q

What comes under organic compounds?

A

1) Nutrients
- glucose, amino acids, lipids
2) MEtabolic wate products
- urea, creatinine, lactic acid
3) Resporatory gases
4) Vitamins
5) Hormones
6) Enzymes.

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20
Q

Water is a…

A

…universal solvent

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21
Q

Water supplies…

A

…tissues (transporter)

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22
Q

Water helps to maintain…

A

…blood volume and pressure

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23
Q

Water distributes…

A

…heat around the body.

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24
Q

Haemopoiesis starts with …

A

…a pluripotential stem cell

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25
Q

In Haemopoiesis, the pluripotential stem cell can…

A

1) self renew
2) give rise to separate cell lineages via committed haemopoietic progenitors, which are restricted in their developmental potential.

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26
Q

Haemopoiesis is the…

A

…formation of blood cells (poiesis = formation of)

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27
Q

one stem cell produces ____ mature blood cells after 20 cell divisions

A

one stem cell produces 1 million (10^6) mature blood cells after 20 cell divisions

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28
Q

precursors capable of responding to …

A

…HP growth factors to increase particular cell line

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29
Q

Haemopoiesis can be split into…

A

…3 major blood cell formation pathways

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30
Q

Thrombopoiesis is the formation of…

A

…platelets (thrombocytes)

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31
Q

Leucopoiesis is the…

A

…formation of white blood cells (leucocytes)

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32
Q

Erythropoiesis is the…

A

…formation of a billion (10^12) new red blood cells (erythrocytes) every day.

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33
Q

Function of Erythropoietin (EPO) ?

A

Erythropoietin is a hormone that your kidneys naturally make to stimulate the production of red blood cells

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34
Q

Erythropoietin (EPO) is a…

A

…growth factor

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35
Q

Platelets known as…

A

…thrombocytes

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36
Q

Platelets are…

A

…Small, nearly colourless irregular spindles/oval discs

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37
Q

Platelets play an …

A

…important role in haemostasis and coagulation

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38
Q

Platelets adhere to …

A

…damaged lining of blood vessel and each other in 1-5 seconds to form PLATELET PLUG

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39
Q

Platelet plugs are…

A

…rather fragile to begin with

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40
Q

encounter of platelets results in creation of …

A

…sticky platelets

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41
Q

platelets release …

A

… several chemicals involved in coagulation process

(ADP, thromboxane, and arachidonic acid)

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42
Q

Function of release of ADP, thromboxane, and arachidonic acid by platelets)

A

Affect local blood flow (vasocon) and platelet aggregation at injury.

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43
Q

Platelets are extremely important …

A

…in controlling microhaemorrages

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44
Q

Thrombopoiesis from …

A

…megakaryoblasts and megakaryocytes (early form of thrombocytes)

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45
Q

Rupture of megakaryocytes releases…

A

…2000-3000 platelets

  • anucleated (no nucleus)
  • limited plasma membrane
  • short life span (7 days)
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46
Q

Coagulation pathways

A

powerpoint slides.

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47
Q

Neutrophil:

A
  • spherical shape
  • multi-lobed nucleus
  • small, pink-purple-staining cytoplasmic granules
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48
Q

3 types of Polymorphonuclear Granulocytes which are:

A

1) Neutrophil
2) Eosinophil
3) Basophil

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49
Q

Eosinophil:

A
  • spherical shape
  • 2-lobed nucleus
  • large, orange-red-staining cytoplasmic granules
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50
Q

Basophil:

A
  • spherical shape
  • 2-lobed nucleus
  • large, purple-staining cytoplasmic granules
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51
Q

Two types of Agranulocytes whcih are:

A

1) Lymphocytes
2) Monocytes

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52
Q

Lymphocytes:

A
  • spherical shape
  • round, single-lobed nucleus
  • small lymphocytes – hardly any cytoplasm
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53
Q

Monocytes:

A
  • spherical shape
  • kidney-bean or horseshoe shaped nucleus
  • large, “steel blue” cytoplasm
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54
Q

Size of neutrophil?

A

15um

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55
Q

Number of neutrophils ?

A

60%

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56
Q

Function of neutrophil?

A

Cellular defence - phagocytosis of small pathogenic microorganisms

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57
Q

Neutrophil life span?

A

1-4 days

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58
Q

Eosinophil size?

A

15um

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59
Q

Number of eosinophil?

A

4%

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60
Q

Function of eosinophil?

A

Cellular defence – phagocytosis of large pathogens (parasites, protozoa)

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61
Q

Life span of eosinohpil?

A

10-12 days

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62
Q

Basophil size?

A

15 um

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63
Q

Number of Basophil?

A

> 1%

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64
Q

Basophil function?

A

Anti-inflammatory - releases histamine; secretes heparin (anticoagulant)

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65
Q

Basophil life span?

A

1-4 days

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66
Q

Monocytes size?

A

20um

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67
Q

Number of monocytes?

A

6%

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68
Q

Monocytes function?

A

Form tissue macrophages – migrate out of blood - ingest bacteria, cell debris, cancer.

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69
Q

size of lymphocytes?

A

10 um

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70
Q

Number of lymphocytes?

A

30% / 20%

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71
Q

Function of lymphocytes?

A
  • B-cells: Ab production
  • T-cells: cellular immune response
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72
Q

Lifespan of lymphocytes ?

A

4 years (both B-cells and T-cells)

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73
Q

Red corpuscles are over […] w/w haemoglobin (Hb)

A

Red corpuscles are over 95% w/w haemoglobin (Hb)

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74
Q

Hb is a tetramer of …

A

…4 globins

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75
Q

Hb transports oxygen via its …

A

…four haem groups

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76
Q

Each of the 4 globin have its own…

A

…haem group

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77
Q

Each contains…

A

…Fe2+

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78
Q

2,3-diphosphoglycerate site in …

A

…deoxyhaemoglobin

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79
Q

Red cell size?

A

8um in diameter

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80
Q

Red cell have a very…

A

…large surface area:volume

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81
Q

Shape of red blood cells?

A

Biconcave disc

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82
Q

Red blood cells can change…

A

…their shape into a smaller cup shape

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83
Q

What protein in red blood cells give it flexibility?

A

Spectrin (protein in stretchable fibres)

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84
Q

Constituents of red blood cell?

A
  • Hb
  • carbonic anhydrase.
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85
Q

Red blood cells have no…

A

…nucleus, mitochondria, ribosomes

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86
Q

What are the 3 major blood disorders?

A

1) Anaemia
2) Haemophilia
3) Leukaemia

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87
Q

What is anaemia?

A

Anaemia is a subnormal amount of circulating haemoglobin

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88
Q

What are the symptoms of anaemia?

A

lethargy, pallor, and breathlessness

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89
Q

Treatments of anaemia?

A

By finding and rectifying the cause.
Eg: iron loss

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90
Q

Whats pallor?

A

an unhealthy pale appearance.

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91
Q

Severe anaemia requires…

A

…a blood transfusion

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92
Q

Haemophilia A is a …

A

…lack of Factor VIII

93
Q

Haemophilia B is a …

A

…lack of Factor IX

94
Q

Symptoms of haemophilia arise from …

A

…prolonged bleeding, e.g. into joints

95
Q

Treatments of Haemophilia?

A

Treatment by the administration of Factor VIII or IX

96
Q

What is leukaemia?

A

Leukaemia is the uncontrolled proliferation (malignancy) of abnormal white blood cells

97
Q

Symptoms of leukaemia?

A

infections, anaemia, and bleeding

98
Q

Treatment of leukaemia?

A

Chemotherapy, radiotherapy, and on occasion, bone marrow transplantation.

99
Q

The heart lies in the…

A

…mediastinum

100
Q

Whats the heart?

A

A fist-sized muscular organ

101
Q

The heart contains […] chambers.

A

The heart contains 4 chambers.

102
Q

What are the 4 chambers of the heart?

A
  • Right and left atria (receiving chambers)
  • Right and left ventricles (pumping chambers)
103
Q

The heart has two…

A

…functional halves (the right and left side)

104
Q

The two halves is separated by the…

A

…septum

105
Q

The atria is separated by the…

A

…an interatrial wall or septum

106
Q

the ventricles are separated by the…

A

interventricular septum

107
Q

Whats the pericardium?

A

Membrane that surrounds and protects the heart

108
Q

The pericardium consists of…

A

…2 main parts

109
Q

The two main part of the pericardium are…

A

1) fibrous pericardium
- tough connective tissue
2) serous pericardium
- thinner more delicate

110
Q

The serous pericardium is the…

A

…outer parietal layer (fused to fibrous pericar) and the inner visceral layer.

111
Q

Whats the visceral layer?

A
  • a layer of the heart wall
  • adheres tightly to the surface of the heart
112
Q

What is between the outer parietal layer and the inner visceral layer?

A

thin film of serous fluid

113
Q

the Heart Wall consists of…

A

…3 layers

114
Q

The 3 layers of the heart wall:

A

1) epicardium
2) myocardium
≈ 95% of wall
3) endocardium

115
Q

Characteristics of epicardium:

A

thin, transparent outer layer

116
Q

Characteristics of myocardium?

A

responsible for pumping action

117
Q

Characteristics of endocardium?

A

smooth, inner layer

118
Q

Whats systole?

A

Contraction of heart wall (myocardium)

119
Q

Blood is ejected from …

A

…the chamber

120
Q

Whats diastole?

A

Relaxation of heart wall (myocardium)

121
Q

What happens during diastole?

A

Blood fills up the chamber

122
Q

Heart valves are composed of…

A

…dense connective tissue covered by endocardium

123
Q

Four one-way heart valves ensure …

A

…the unidirectional flow of blood

124
Q

Pressure differences cause …

A

…the opening and closing of these valves

125
Q

When pressure is greater behind the valve…

A

…it opens

126
Q

Forward pressure gradient =

A

VALVES OPEN

127
Q

When prressure is greater in front of the valve it…

A

…closes

128
Q

Backward pressure gradient =

A

VALVES CLOSE

129
Q

Atrioventricular (AV) Valves prevent…

A

…backflow from ventricles to atria

130
Q

Types of Atrioventricular (AV) Valves?

A

tricuspid
bicuspid

131
Q

Semi-lunar Valves prevent…

A

…backflow from major arteries to ventricles

132
Q

Types of Semi-lunar Valves?

A
  • pulmonary valve between RV and pulmonary arteries
  • aortic valve between LV and aorta
133
Q

Describe tricuspid valve?

A
  • (3 cusps or leaflets) between RA and RV
  • Right AV valve
134
Q

Describe bicuspid valve?

A
  • (mitral) (2 cusps or leaflets) between LA and LV
  • Left AV valve
135
Q

Myocardium =

A

Cardiac Muscle

136
Q

Cardiac muscle cells (cardiocytes / cardiomyocytes) – unique to …

A

…heart

137
Q

Size of cardiac muscle fibre?

A
  • 50-100 µm long, 14 µm in diameter
  • one centrally located nucleus is present
138
Q

The cardiac muscle is …

A

…Myogenic

139
Q

Explain the cardiac muscle being myogenic.

A

capable of intrinsic contraction without input from CNS.

140
Q

[…] of cardiac muscle cells is made up of […]

A

25% of cardiac muscle cells is made up of mitochondria.

141
Q

Ends of cardiac muscle fibres connect to …

A

…neighbouring fibres by irregular transverse thickenings of sarcolemma

142
Q

Adjacent cardiac muscle fibres joined at …

A

…intercalated discs

143
Q

intercalated discs contain…

A

desmosomes
gap junctions

144
Q

desmosomes hold …

A

…the cardiac muscle fibres together

145
Q

Functions of gap junctions?

A

1) allow muscle action potentials to spread (conduct) from one cardiac muscle fibre to its neighbours
2) allow the entire myocardium of the atria or the ventricles to contract as a single, coordinated unit

146
Q

The Conduction System of the Heart is a …

A

…life-long rhythmical electrical activity

147
Q

The Conduction System of the Heart is enabled because the cardiac muscle is…

A

…specialised (with autorythmic fibres).
(SELF EXCITABLE)

148
Q

The cardiac muscle generates…

A

…action potentials that trigger heart contractions

149
Q

2 important functions of the hearts conduction system:

A
  • act as a pacemaker
  • form the cardiac conduction system
150
Q

Cardiac Conduction System provides…

A

…a path for each cycle of cardiac excitation to progress

151
Q

Cardiac Conduction System ensures…

A

…Ensures that chambers become stimulated to contract in coordinated way

152
Q

Rhythm controlled by…

A

…the cardiac conduction system

153
Q

The cardiac cycle includes…

A

…all the events associated with one heart beat

154
Q

Cardiac cycle consists of…

A

…systole and diastole of the atria PLUS systole and diastole of the ventricles

155
Q

The atria and ventricles alternatively …

A

…contract and relax
- forces blood from high pressure to low pressure areas

156
Q

As a chamber of the heart contracts…

A

…blood pressure within it increases

157
Q

Each ventricle:

A
  • expels the same volume of blood per beat
  • the same pattern exists for both pumping chambers
158
Q

Speed of cardiac cycle?

A

0.8 sec when heart rate = 75 beats/min

159
Q

Process of cardiac cycle

A

1) Action potential (electrical impulse) from the SA node
2) Atrial Systole (0.1 seconds)
3) Atria contract (ventricles relaxed)
4) AV valves open
5) Ventricles fill up
6) Semi-lunar valves closed
7) Action potential reaches AV node
8) Ventricular systole (0.3 sec)
9) Ventricles contract
(Atria relaxed = atrial diastole)
10) AV valves forced closed
11) Semi-lunar valves forced open
12) Ejection of blood begins
13) Relaxation period (0.4 sec)
14) Semi-lunar valves close
15) Atria fill up; AV valves closed

160
Q

Blood carried in …

A

…closed system of vessels that begins/ends at the heart

161
Q

The three major types of blood vessels are …

A

…arteries, capillaries and veins

162
Q

Arteries and veins are composed of …

A

…three layers

163
Q

What are the three layers of arteries and veins?

A

Tunica adventitia (or externa), media, intima.

164
Q

tunica adventitia (externa) (“coat that comes first”) made of…

A

…strong, flexible (loose) fibrous connective tissue

165
Q

Why is the tunica adventitia made up of this strong and fibrous connective tissue?

A

Holds vessels open and prevents tearing of the vessel walls during body movements.

166
Q

The tunica adventitia is thicker in….

A

…arteries than in veins.

167
Q

in arteries, tunica adventitia is usually…

A

…a little thinner than middle layer

168
Q

in veins, tunica media is the …

A

…thickest of the three layers

169
Q

tunica media (“middle coat”) made of…

A

…a layer of smooth muscle tissue sandwiched together with a layer of elastic connective tissue

170
Q

Smooth muscle in tunica media …

A

…permit changes in blood vessel

171
Q

smooth muscle also innervated by …

A

…autonomic nerves

172
Q

Smooth muscle in tunica media supplied with blood by…

A

…tiny vaso vasorum

173
Q

tunica media is generally thicker in…

A

…arteries than in veins

174
Q

tunica intima (“innermost coat”)
made up of …

A

…endothelium

175
Q

tunica intima continuous with…

A

…endothelium that lines the heart

176
Q

in arteries tunica intima provides completely …

A

… smooth lining

177
Q

In veins, tunica intima forms…

A

…semilunar valves

178
Q

What is lumen?

A

central blood-containing space that is surrounded by the three tunica

179
Q

As blood vessels decrease in diameter…

A

… the relative thickness of their walls also decreases

180
Q

there are differences in amounts of…

A

…tissue components present in arteries and veins

181
Q

4 types of tissue building blocks in blood vessels:

A

1) Lining endothelial cells
2) Collagen fibres
3) Elastic fibres
4) Smooth muscle cells.

182
Q

Capilleries are composed of…

A

…a single layer of endothelial cells and sparse basal lamina surrounded by a basement membrane.

183
Q

Why are capillaries thin?

A

thinness allows for efficient exchange of materials between blood plasma and interstitial fluid of surrounding tissues.

184
Q

Three types of …

A

…arteries.

185
Q

Three types of artery whcih are:

A

Elastic (conducting), muscular (distributing) and arterioles (resistance vessels)

186
Q

Elastic (Conducting) Arteries are the…

A

…Largest in the body; thick-walled; near the heart

187
Q

Elastic (Conducting) Arteries includes…

A

…the aorta and some of its major branches

188
Q

all three tunica contain …

A

…elastin

189
Q

Why do tunica intima contain elastin?

A

withstand and smooth out blood pressure fluctuations

190
Q

large lumen allows for…

A

…low-resistance conduction of blood

191
Q

Elastic (Conducting) Arteries have a …

A

…large lumen

192
Q

Elastic (Conducting) Arteries serve as…

A

…pressure reservoiurs.

193
Q

Muscular (Distributing) Arteries Carry blood …

A

…farther away from heart to specific organs/areas

194
Q

Muscular (Distributing) Arteries are smaller in….

A

…diameter, thicker tunica media, with more smooth muscle

195
Q

Muscular (Distributing) Arteries active in…

A

…vasoconstriction

196
Q

Arterioles are the…

A

…Smallest arteries

197
Q

arterioles are critical in…

A

…blood flow regulation throughout body

198
Q

Arterioels control…

A

…blood flow into capillary beds via vasodilation and vasoconstriction

199
Q

arterioles help regulate….

A

…blood pressure

200
Q

Metarteriole is a…

A

…Short vessel that connects a true arteriole with the proximal end of 20-100 capillaries

201
Q

Metarteriole extends through…

A

…the capillary bed

202
Q

Proximal ends of metarteriole encircled by…

A

…regulatory valves.

  • Precapillary sphincters
  • regulate blood flow
203
Q

Possible for blood passing through a metarteriole into a thoroughfare channel to …

A

…bypass capillary bed

204
Q

Capillaries are the …

A

…smallest blood vessels

205
Q

Walls of capilleries consist of…

A

…thin tunica intima

206
Q

Size of capilleries?

A

One endothelial cell thick

207
Q

Capilleries allow only…

A

…one rbc to pass at a time

208
Q

What stabilizes capillary walls?

A

pericytes on the outer surface stabilise their walls
.

209
Q

How many capilleries in human body?

A

in excess of 1 billion in the body

210
Q

Where are capilleries mostly found in great numbers?

A

more found in liver and heart than cartilage and epithelium

211
Q

Thin capillary wall allows…

A

…efficient exchange of nutrients between blood plasma and tissue cells

212
Q

Capilleries are known as…

A

…primary exchange vessels

213
Q

There are three structural types of capillaries:

A

Continuous, fenestrated, and sinusoid

214
Q

Describe Continuous (or tight/closed) capillaries

A
  • continuous lining of endothelial cells
  • Small openings called intercellular clefts between them.
215
Q

Continuous (or tight/closed) capillaries typically found in…

A

…skeletal muscle, lung, cns, retina

216
Q

prevent passage of large toxic molecules prevent…

A

…passage of large toxic molecules

217
Q

Fenestrated (or normal) capillaries also have…

A

…“small holes” through plasma membrane

218
Q

Fenestrated (or normal) capillaries allow…

A

…ready exchange of metabolites to kidneys, small intestines.

219
Q

Sinusoid capillaries is a…

A

…basement membrane incomplete or absent

220
Q

Why do Sinusoid capillaries
have larger pores?

A

increased permeability in liver and bone marrow.

221
Q

Total exchange surface of capilleries?

A

> 6000m2 of exchange surface in the capillaries

222
Q

Microcirculation = ?

A

Microcirculation = blood flow through arterioles, capillaries and venules

223
Q

true capillaries receive …

A

…blood from metarteriole; return it to thoroughfare channel at distal end

224
Q

How many capilleries per capillary bed?

A

20-100 capillaries per capillary bed

225
Q

precapillary sphincters regulate …

A

…blood volume inflow and rate of passage

226
Q

closed or partially closed =

A

↓ blood flow into capillary bed

227
Q

blood passes directly through metarteriole to…

A

…thoroughfare channel, bypassing capillary bed

228
Q

Capillary Beds connects…

A

…terminal arteriole directly with postcapillary venule

229
Q

Capillary Beds also known as….

A

…arteriovenous shunt