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Physiology 2nd Midterm > Circulatory System 1 > Flashcards

Circulatory System 1 Flashcards

1
Q

The circulatory system consists of two systems. What are they?

A

Cardiovascular system + Lymphatic system

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2
Q

What does the cardiovascular system consist of

A

Heart
Blood vessels
Blood

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3
Q

What does the lymphatic system consist of

A

Lymphoid tissue
Lymphatic vessels
Lymph

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4
Q

Functions of circulatory system

A
  1. Transport:
    - respiratory: oxygen and carbon dioxide
    - nutritive: digest food materials
    - excretory: metabolic wastes, excess water and ions
  2. Regulation:
    - hormonal: site of origin to target tissues
    - temperature: diversion of blood between superficial and deep vessels
  3. Protection:
    - clotting: protection against blood loss when vessels are damaged
    - immune: protection by white blood cells against pathogen
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5
Q

Blood is about ______ % of the total body weight

A

8%

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6
Q

Blood is either ___________ blood or __________ blood

A

Arterial blood
Venous blood

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7
Q

Blood consists of:

A
  1. Plasma
  2. Formed elements
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8
Q

What is plasma

A

Straw-colored (pale yellow) liquid which consists of water and dissolved solutes

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9
Q

What is the liquid part of blood

A

Plasma

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10
Q

We said plasma consists of water and dissolved solutes.
What are these dissolved solutes?

A
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11
Q

Difference between serum and plasma

A

Plasma has fibrinogen + no blood clotting
Serum lacks fibrinogen due to blood clotting

NOTE:
Blood centrifuge + anticoagulant = plasma
Blood centrifuge - anticoagulant = serum

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12
Q

What makes up most of the organic molecules in plasma ?

A

Protein

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13
Q

What are some electrolytes in plasma

A

Na+
K+
Ca2+
Cl-
HCO3-

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14
Q

What are some organic molecules in plasma

A

Cholesterol
Glucose
Protein
Urea
Lactic acid

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15
Q

What are some hormones present in plasma

A

Insulin
Testosterone
Growth hormone
Etc

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16
Q

What are some enzymes in plasma

A

Lactate dehydrogenase (LDH)
Creative phosphokinase (CPK)

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17
Q

Plasma proteins make up ______% of plasma volume

A

7% - 9%

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18
Q

What are some plasma proteins ?

A

Albumins
Globulins
Fibrinogen

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19
Q

Which plasma protein accounts for 55% to 60% of the plasma proteins ?

A

Albumins

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20
Q

Albumins account for _____% to _____% of the plasma proteins

A

55% to 60 %

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21
Q

What is the function of albumin

A

Maintain blood volume and pressure

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22
Q

What produces albumin

A

Liver

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23
Q

We categorized globulins into 2 groups which are

A
  1. Alpha globulin and Beta globulin
  2. Gamma globulins
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24
Q

Name a function of alpha globulin and beta globulin

A

Transport lipids and fat-dissolved vitamins

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25
Q

What organ produces alpha and beta globulins

A

Liver

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26
Q

What are gamma globulins ?

A

Antibodies

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27
Q

Function of gamma globulins

A

Immunity

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28
Q

What produces gamma globulins ?

A

B-lymphocytes

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29
Q

Function of fibrinogen

A

Blood clotting

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30
Q

What produces fibrinogen

A

Liver

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31
Q

Plasma proteins produced by the liver are

A

Albumins
Alpha and beta globulins
Fibrinogen

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32
Q

What are formed elements in blood?

A

Blood cells (erythrocytes, leukocytes, thrombocytes)

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33
Q

What are erythrocytes

A

Red blood cells

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34
Q

What are the most abundant cells in blood?

A

Erythrocytes (RBC)

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35
Q

What is the shape of RBC and why is this shape significant

A

Biconcave
Increases surface area for gas exchange

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36
Q

True or false
RBC does NOT have a nucleus

A

True

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37
Q

What does the RBC contain that gives blood its red color

A

Hemoglobin

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38
Q

Structure of hemoglobin

A

4 globin chains, each with iron-containing heme group

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39
Q

Function of hemoglobin

A

Carries oxygen around the body

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40
Q

Each hemoglobin can bind to how many oxygen molecules ?

A

4

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41
Q

True or false
The iron atom of the heme group can irreversibly bind oxygen as the blood travels between the lungs and the tissues

A

False

Reversibly

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42
Q

How long do RBCs live for?

A

120 days

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43
Q

What are thrombocytes

A

Platelets

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44
Q

What are the smallest of the formed elements in blood

A

Platelets

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45
Q

What are platelets

A

Fragments of large bone marrow cells called megakaryocytes

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46
Q

Do platelets have a nucleus ?

A

No

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47
Q

True or false
Platelets move in an amoeboid fashion

A

True

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48
Q

Function of platelet

A

Blood clotting

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49
Q

True or false
Platelets constitute most of the clot mass

A

True

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50
Q

What are leukocytes ?

A

White blood cells

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51
Q

Which blood cells are referred to as “protective cells” of the body

A

WBCs

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52
Q

Do WBCs contain a nucleus

A

Yes

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53
Q

True or false
WBCs move in amoeboid fashion

A

True

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54
Q

Why is it important that WBCs move in amoeboid fashion?

A

Allows them to cross the intact capillary wall to the site of tissue damage or infection (by diapedesis or extravasation)

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55
Q

What is diapedesis

A

Passage of blood cells through intact walls of the capillaries

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56
Q

What is extravasation

A

Leakage of blood, lymph, or other fluid from a blood vessel into the tissue

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57
Q

WBCs are either ________ or __________

A

Granular or Agranular

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58
Q

Granular leukocytes include :

A

(Hint: BEN)

Basophils
Eosinophils
Neutrophils

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59
Q

Agranular leukocytes include:

A

Monocytes
Lymphocytes

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60
Q

Which cells are the most abundant type of WBCs in the circulation (50-70%)

A

Neutrophils

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61
Q

Neutrophils make up ___ % - ____% of WBCs in circulation

A

50-70%

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62
Q

Which WBC type are the first cellular responders to tissue injury and infection

A

Neutrophils

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63
Q

There are certain molecules on the surface of RBCs; what are these molecules called

A

Antigens

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64
Q

Which WBC secretes antibodies as a part of our body’s defense system

A

B-lymphocytes

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65
Q

What happens when an RBC antigen is exposed to its corresponding antibody

Example: Antigen B and B antibodies

A

RBC agglutination and hemolysis

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66
Q

What antigen does blood type A have

A

Antigen A

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67
Q

What antigen does blood type B have

A

Antigen B

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68
Q

What antigen does blood type AB have

A

Antigens A and B

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69
Q

What antigen does blood type O have

A

No antigens

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70
Q

What antibody does blood type A have

A

Anti-B antibodies

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71
Q

What antibody does blood type B have

A

Anti-A antibodies

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72
Q

What antibody does blood type AB have

A

No antibodies against A and B

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73
Q

What antibody does blood type O have

A

Both Anti-A and Anti-B antibodies

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74
Q

What blood type can a person with Type A blood accept

A

A blood
O blood

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75
Q

What blood type can a person with Type B blood accept

A

B blood
O blood

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76
Q

What blood type can a person with Type AB blood accept

A

A blood
B blood
O blood

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77
Q

What blood type can a person with Type O blood accept

A

O blood only

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78
Q

Which blood type is the universal recipient

A

Type AB

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79
Q

What blood type is the universal donor

A

Type O

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80
Q

True or false
A person with type A blood can receive blood from a donor with Type AB

A

False

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81
Q

Can a person with a + Rh donate blood to a person with -Rh ?

A

No because a person with -Rh has Anti-Rh antibodies

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82
Q

Can a person with -Rh donate blood to a person with +Rh

A

Yes

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83
Q

Can O+ donate blood to O- ?

A

No because O- has anti-Rh antibodies

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84
Q

The cardiovascular system consists of two main sub-circuits; what are they

A

Systemic circulation
Pulmonary circulation

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85
Q

Arteries transport blood ___________ the heart

A

Away from

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86
Q

Veins transport blood _____________ the heart

A

Towards

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87
Q

What are capillaries

A

Delicate and small blood vessels that are the sites of gas, nutrient and waste exchange between blood and tissue

88
Q

Arteries usually carry what kind of blood

A

Oxygenated

89
Q

Veins usually carry what kind of blood

A

Deoxygenated

90
Q

Which arteries do NOT carry oxygenated blood

A

Pulmonary arteries

91
Q

Which veins do NOT carry deoxygenated blood

A

Pulmonary veins

92
Q

Pulmonary circulation

A

Moves blood between HEART and LUNGS

(RA - RV - pulmonary arteries - lungs - absorbs O2 and releases CO2 - pulmonary veins - back to heart)

93
Q

Systemic circulation

A

Moves blood between HEART and rest of the BODY

(LA - LV - Aorta - arteries - body - releases O2 and absorbs CO2 - veins - back to heart)

94
Q

What is the heart

A

A cone-shaped muscular organ, located in the thorax between the lungs

95
Q

How many chambers does the heart have

A

4

96
Q

What are the 4 chambers of the heart

A

Right atrium
Left atrium
Right ventricle
Left ventricle

97
Q

Where does the right atrium receive blood from?

A

Superior vena cava
Inferior vena cava

(Also coronary sinus but not mentioned)

98
Q

Where does left atrium receive blood from

A

Pulmonary veins

99
Q

Both ventricles receive blood from ________

A

The atria

100
Q

The right ventricle pumps out blood into ___________.

A

Pulmonary arteries

101
Q

The left ventricle pumps out blood into _____________.

A

Aorta

102
Q

Describe the apex and base of the heart

A

Apex is located inferiorly whereas the base is located superiorly

103
Q

Right and left atria open in corresponding ventricles via one way valves ; what are they ?

A

RA to RV : tricuspid valve
LA to LV: bicuspid valve (mitral valve)

104
Q

What separates the right side of the heart from the left side

A

Septum

105
Q

What is the importance of the septum that separates the right and left sides of the heart?

A

Prevents mixing of oxygenated and deoxygenated blood

106
Q

How does blood flow through the heart

A
107
Q

What ensures the one-way flow of blood through the heart?

A

Valves

108
Q

What are the atrioventricular valves of the heart

A

Tricuspid valve (between RA and RV)
Bicuspid valve or mitral valve (between LA and LV)

109
Q

Describe the structure of the valves

A

Valve cusps or leaflets are attached by fibrous cords called chordae tendineae to papillary muscle that are located on the inside of the ventricular walls

110
Q

What is the significance of the valve’s structure

A

Prevents the cusps from swinging back into the atria during ventricular contraction

111
Q

What are the semilunar valves

A

Aortic valve
Pulmonary valve

112
Q

Cardiac valves are PASSIVELY operated by :

A

The difference in blood pressure between atria & ventricles OR between ventricles & outflow vessels

This is why they are one-way valves

113
Q

True or False
Cardiac valves are analogous to doors that open in one direction, but not the other .

A

True

114
Q

Compare the walls of arteries, veins, and capillaries

A

Arteries have muscular walls and smaller lumen
Veins have thinner walls and bigger lumen
Capillaries have a single layer wall of endothelial cells

115
Q

What is the significance of the capillary’s single layer wall ?

A

Allows gas exchange

116
Q

Compare the pressure in arteries and veins

A

Arteries have HIGH pressure
Veins have LOWER pressure

117
Q

Since veins have lower pressure than of that in arteries, what aids venous flow to the heart?

A

Venous valves

118
Q

Histology: both arteries and veins are composed of three layers ; what are they ?

A

Tunica interna (tunica intima)
Tunica media
Tunica externa (tunica adventitia)

119
Q

What does tunica interna consist of

A

Elastic tissue fibers
Basement membrane
Inner endothelium

120
Q

What does tunica media consist of?

A

Smooth muscle cells
Elastic tissue fibers

121
Q

What does tunica externa consist of

A

Connective tissue

122
Q

Functional role of arterial and venous vascular wall

A

Venous vascular wall:
- most blood is stored in veins
- HIGHLY distensible or compliant (expand easily)

Arterial vascular wall:
- contain less blood compared to veins
- wall has LIMITED ability to distend

123
Q

Not a question . Just know this simple fact.

A

Flow path :

Artery - arteriole - capillary - venule - veins

124
Q

What is the cardiac cycle

A

Repeating pattern of contraction (systole) and relaxation (diastole) of the atria and ventricles

125
Q

Average heart rate

A

70-75 beat/min

126
Q

Each cardiac cycle lasts ________

A

0.8 seconds

127
Q

How much of the cardiac cycle (0.8 seconds) is diastole and systole

A

Diastole

128
Q

Events of cardiac cycle

A
129
Q

How long is diastole

A

0.5 seconds

130
Q

How long is systole

A

0.3 seconds

131
Q

What happens during diastole

A

Atria contract
Ventricles relax and fill

132
Q

What happens in systole

A

Atria are relaxed
Ventricles contract

133
Q

Describe ventricular filling during diastole

A

Ventricles are 80% filled with blood PASSIVELY
While the final 20% is added when atria contract

134
Q

Systole and diastole refer to the contraction and relaxation of ________________.

A

Ventricles

135
Q

When the ventricle fill up with blood , this blood volume is called

A

End diastolic volume EDV

(80% of EDV occurs passively and the final 20% is added with atrial contraction)

136
Q

When ventricles contract during systole , how much blood is actually ejected from the EDV?

A

2/3 of EDV is ejected

(The blood volume that was ejected is called stroke volume)

137
Q

What is stroke volume (SV)

A

Volume of blood ejected from each ventricle during one cardiac cycle (so each heartbeat)

138
Q

Since the stroke volume (SV) is 2/3 of the EDV , what is the remaining volume of blood in the ventricle called ?

(The remaining 1/3 after ejection)

A

End systolic volume ESV

139
Q

How to calculate stroke volume ?

A
140
Q

What is the SV of a healthy man, if his EDV = 120 ml, and his ESV = 50 ml?

A

SV = 120 - 50 = 70 ml/beat

141
Q

Understand this

A

During diastole, ventricles are being filled up

When ventricles are full, that volume of blood is called end diastolic volume EDV

During systole, blood is ejected and the volume of that blood ejected is stroke volume SV

At the end of systole, the volume of blood left in the ventricle is called end systolic volume ESV

142
Q

What is the usual EDV in an adult human

A

120 ml

143
Q

After ventricles ar filled with blood, ventricular muscle contracts WITHOUT a change in length. What is this contraction called

A

Iso-volumetric contraction

144
Q

What is isovolumetric contraction

A

Ventricles contract with no corresponding volume change or change in length

145
Q

Describe the ventricular pressure and volume changes during cardiac cycle

A
146
Q

What is the purpose of iso-volumetric contraction

A

Increases intra-ventricular pressure so that it is eventually much higher than aortic pressure

147
Q

What needs to happen in terms of pressure in order for ejection to occur

A
148
Q

What happens to pressure and volume during ejection ?

A
149
Q

What occurs after ejection?

A

Iso-volumetric relaxation

150
Q

True or false
Iso -volumetric relaxation causes change in volume?

A

False

151
Q

Purpose of isovolumetric relaxation

A

Decrease in intra-ventricular pressure to allow for filling of ventricle

152
Q

Describe volume and pressure during filling .

A
153
Q

At the end of passive ventricular filling what occurs and why?

A

Atrial systole (atrial contraction) to deliver the final (20%) volume of blood into ventricles

154
Q

Notice the volume and pressure during systole and diastole

A

Systole :
Pressure increases then drops
Volume decreases to minimum

Diastole:
Pressure is low and constant
Volume increases

155
Q

What produces heart sounds that can be heard through a stethoscope

A

Closure of valves

156
Q

What do heart sounds sound like?

A

Lub-dub

157
Q

What produces the FIRST heart sound (S1)

A

Closure of AV valves

(Which occurs when ventricular pressure exceeds atrial pressure)

158
Q

What produces the SECOND heart sound (S2)

A

Closure of semilunar valves

(Which occurs when ventricular pressure falls below the pressure in arteries ; aorta + pulmonary arteries)

159
Q

What is phase 1 of the cardiac cycle

A

Mid-to-late diastole

160
Q

What occurs in Phase 1 of cardiac cycle

A
  1. Ventricular filling
  2. Atrial contraction
161
Q

When is phase 2 of cardiac cycle ?

A

Systole (early systole)

162
Q

What occurs during phase 2 of cardiac cycle

A

Iso-volumetric contraction

(To increase intra-ventricular pressure)

163
Q

When is phase 3 of cardiac cycle

A

Systole

164
Q

What occurs in phase 3 of cardiac cycle

A

Ventricular ejection

165
Q

When is phase 4 of cardiac cycle

A

Diastole (early diastole)

166
Q

What occurs in phase 4 of cardiac cycle

A

Isovolumetric relaxation

167
Q

Understand what occurs in each phase

A

Phase 1: (mid-late diastole) ventricular filling + atrial contraction

Phase 2: (systole) iso-volumetric contraction

Phase 3: (systole) ventricular ejection

Phase 4: (early diastole) isovolumetric relaxation

168
Q

State of valves during phase 1 of cardiac cycle
(Ventricular filling + atrial contraction)

A

AV: open
Semilunar: closed

169
Q

State of valves during phase 2 of cardiac cycle
(Isovolumetric contraction)

A

AV: closed
Semilunar: closed

170
Q

State of valves during phase 3 of cardiac cycle
(Ventricular ejection)

A

AV: closed
Semilunar: open

171
Q

State of valves during phase 4 of cardiac cycle
(Isovolumetric relaxation)

A

AV: closed
Semilunar: closed

172
Q

Function of heart

A

Contract and pump blood to the body

173
Q

In order for the heart to contract and pump blood, it must be ________________ _____________ first.

A

Electrically activated

174
Q

There are two main types of cells in the heart

A

Conducting cells (1%)
Contractile cells (99%)

175
Q

What are conducting cells ?

A

Specialized muscle cells that initiate electrical impulses and conduct them rapidly through the heart

176
Q

What are contractile cells

A

Cardiomyocytes which make up most of the atrial and ventricular tissue

Also known as “working cells of the heart”

177
Q

Which type of cells in the heart are known as “working cells” of the heart?

A

Contractile cells (cardiomyocytes)

178
Q

The heart shows automaticity ; what does that mean

A

No requirement for neural input

(So it can create electrical impulses on its own thus does not depend on the nervous system to be able to beat and pump blood)

179
Q

What is sinoatrial node (SA node)

A

Pacemaker of the heart

A region of the heart that functions as a pacemaker and generates automatic electrical activity which stimulates the rest of the heart

180
Q

The action potential spontaneously generated by the SA node is ___________ (same or different) from the action potentials produced by the rest of the heart cells.

A

Different

181
Q

Adjacent cardiomyocytes are connected by electrical synapses called

A

Gap junctions

182
Q

What is the importance of gap junctions between cardiomyocytes ?

A

Allows action potentials to directly and rapidly spread from one cell to another (synchronized contractions)

183
Q

Where are electrical impulses generated in the heart

A

SA node

184
Q

What is AV node and what is its importance ?

A

Atrioventricular node located in the inferior RIGHT atrium.

Purpose: gives SMALL DELAY before continuation of impulses to the bundle of His

185
Q

Why is it important for the AV node to cause a small delay in conduction of impulses ?

A

So that the atria and ventricles don’t all contract at the same exact time , disrupting the one way flow of blood in the heart

186
Q

Where is bundle of His

A

Located in the septum and sends fibers to the ventricles

187
Q

What do purkinje fibers do

A

Spread the impulse through the ventricles rapidly

188
Q

Know the conducting path in the heart

A
  1. SA node: generates and conducts impulses
  2. AV node: delays impulses before continuation
  3. Bundle of His: sends impulse to ventricles
  4. Purkinje fibers: spreads impulses throughout ventricles
189
Q

What are the 3 phases of SA node

A

Phase 0 : upstroke
Phase 3: repolarization
Phase 4: spontaneous depolarization or pacemaker potential

190
Q

What causes phase 0 (upstroke) of SA node action potential

A

Inward Ca2+ current

191
Q

What causes phase 3 (repolarization) of SA node action potential

A

outward K+ current

192
Q

What causes phase 4 (spontaneous depolarization or pacemaker potential) of SA node action potential

A

Influx of “funny” Na+ current through HCN channels

193
Q

Which phase of the SA node action potential is the longest and accounts for the automaticity of the SA node?

A

Phase 4

194
Q

What are the 5 phases of the myocardial action potential

A

Phase 0: upstroke

Phase 1: initial repolarization

Phase 2: plateau

Phase 3: repolarization

Phase 4: resting membrane potential

195
Q

What causes Phase 0 of the myocardial action potential

A

Inward Na+ current

196
Q

What causes Phase 1 of the myocardial action potential

A

Outward K+ current and closure of Na+ channels inactivation gates

197
Q

What causes Phase 2 of the myocardial action potential

A

Net current flow across membrane is 0

198
Q

What causes Phase 3 of the myocardial action potential

A

Outward K+ current

199
Q

What causes Phase 4 of the myocardial action potential

A

Membrane potential returns to resting level -85 mV and is stable

(Inward and outward currents are equal)

200
Q

Understand the phases of SA node action potential

A
201
Q

Understand the 5 phases of the myocardial action potential

A
202
Q

The electrical activity of the heart can be measured on the surface of the skin using an instrument called

A

Electrocardiograph

203
Q

The recorded tracing from the electrocardiograph is called

A

Electrocardiogram (ECG or EKG)

204
Q

True or false
ECG is a recording of action potentials

A

False !

Although it results from the production and conduction of action potentials in the heart, it actually reflects the overall spread of electrical activity during a cardiac cycle

205
Q

_________ is a simple and fast test to evaluates the heart’s electrical system to assess for heart disease

A

ECG

206
Q

Each cardiac cycle produces 3 distinct ECG waves

A

P wave

QRS complex

T wave

207
Q

What does the P wave represent

A

Atrial depolarization

(Atria depolarize and contract)

208
Q

What does the QRS complex represent

A

Ventricular depolarization

(Ventricles depolarize and contract)

NOTE: atria repolarize during ventricular depolarization

209
Q

What does the T wave represent

A

Ventricular repolarization

(Ventricles repolarize and relax)

210
Q

What wave is NOT visible in the ECG?

A

Atrial repolarization

211
Q

Read ECG

A

Normal rhythm

212
Q

Read ECG

A

Bradycardia

(HR < 60 beats/min)

213
Q

Read ECG

A

Tachycardia (HR> 100 beats/min)

214
Q

Bradycardia

A

Slow heart rate

215
Q

Tachycardia

A

Fast heart rate

Physiology 2nd Midterm (7 decks)

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