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Bio 20 IB > Circulation/Immunity > Flashcards

Circulation/Immunity Flashcards

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1
Q

What are three functions of the circulatory system?

A

Transportation of (gases, nutrients, watse, hormones), temperature regulation, protection/repair

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2
Q

What three systems is the coronary system made up of?

A

Systemic, pulmonary, and coronary (cardiac) system

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3
Q

What structure does blood enter the heart from?

A

The atriums

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3
Q

What are the three major components of the circulatory system?

A

Heart, blood vessels, blood cells

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3
Q

Which atrium receives blood from the lungs? Body?

A

Left from lungs and right from the body.

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4
Q

What are the small chambers of the heart called? Large chambers?

A

Small=atriums, large=ventricles

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5
Q

What structure of the heart pushes blood out?

A

The ventricles

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6
Q

What is the septum in the heart? What is its purpose?

A

Thick muscular wall that separates the left and right side of the heart.

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6
Q

Which ventricle pushes blood out to the heart? To the lungs?

A

Right ventricle=lungs, left ventricle=heart

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7
Q

What does the vena cava do?

A

Collect oxygen-poor blood from body into the right atrium.

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8
Q

How many vena cavae are there? What differientiates them?

A

Two vena cavae, super collects blood from head, chest, arms. Inferior collects blood from the bottom half of the body.

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8
Q

Wat does the pulmonary vein carry?

A

Oxygenated blood from the lungs.

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9
Q

What does the coronary artery do? Coronary vein?

A

Coronary artery branches from aorta and supplies heart with nutrients and oxygen. The coronary vein removes CO2 and waste from the heart.

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9
Q

What does the pulmonary trunk branch into?

A

Pulmonary arteries

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10
Q

What does the pulmonary trunk do?

A

Carries oxygen poor blood from the right ventricle to lungs.

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11
Q

What does the aorta carry? From where? What does it branch into?

A

Carries oxygen rich blood from left ventricle to the body. It branches into arteries.

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12
Q

What is the bicuspid ‘(mitral) valve?

A

A valve between the left atria and ventricle. These two valves are attached to the ventrical wall with chordae tendonae.

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12
Q

Name two atrioventrical valves.

A

Bicuspid valve and tricuspid valve

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13
Q

Where is the pulmonary semi-lunar valve located?

A

Between the right ventricle and the pulmonary artery.

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13
Q

What separates the right atrium from the right ventricle?

A

The tricuspid valve.

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14
Q

What is between the left ventricle and the aorta?

A

The aortic semilunar valve.

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15
Q

Describe the pathway of blood through the heart.

A

Enters right atrium from vena cavae then moves to the right ventricle out of the pulmonary artery to the lungs. It then circles to the pulmonary veins to the left atrium to the left ventricle then through the aorta to the body.

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16
Q

How are the arterial walls designed? What does this create/allow for?

A

The walls of the arteries are elastic and this allows for them to expand when the ventricle contracts and snap back to help push blood along. This creates the pulse.

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16
Q

Do arteries carry blood away from or to the heart?

A

Carry blood away from the heart.

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17
Q

Are the arteries under low blood pressure or high?

A

High

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18
Q

When the ventricles contract, what happens to the arteries?

A

They expand.

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19
Q

What are small arteries called? How do they control blood flow in the body?

A

They are called arterioles and they have precapillary sphincters to control blood flow.

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20
Q

How are the walls of the capillaries designed?

A

Permeable walls so gas/nutrient exchange occurs here.

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21
Q

How big are capillaries?

A

One cell thick, they are very small vessels.

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22
Q

What do capillaries do?

A

They connect arteries to veins.

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23
Q

What are small veins called? What does it lead from?

A

Venules which lead from capillaries.

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24
Q

Do veins carry blood away or towards the heart?

A

Towards the heart.

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25
Q

Are veins more elastic or less elastic than arteries? Larger or smaller?

A

Less elastic but larger than arteries.

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26
Q

What moves blood along in veins?

A

Muscle contractions

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27
Q

How is backflow of blood prevented in the veins?

A

By valves

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27
Q

Why do veins have low or no pressure?

A

Because of their large lumens that decreases resistance.

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27
Q

Do arteries have valves? What prevents backflow of blood?

A

The aortic valve.do not have valves since the high pressure nature of the blood in the arteries wont allow for backflow.

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27
Q

Are veins low or high pressure?

A

Low or no pressure.

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28
Q

What is a varicose vein?

A

A vein with broken valves so backflow of blood occurs.

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29
Q

Why are the walls of the arteries thick and muscular?

A

To keep the lumen small so that high blood pressure occurs and the muscular walls is for vasodilation and vasoconstriction.

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29
Q

What makes the heart contract?

A

The sinoatrial node

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30
Q

Where is the sinoatrial node located?

A

In the right atrial wall.

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31
Q

What is the sinoatrial node made of?

A

A collection of uniquely structured cardiac muscle cells

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32
Q

How many nuclei does a cardiac muscle cell have?

A

One nucleus

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32
Q

How can the heart beat outside the body?

A

It spontaneously initiates muscle contraction without other nerve signals.

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32
Q

What is it called when cells contatc in the absence of nerve stimulation?

A

Myogenic

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32
Q

What type of muscle is the cardiac muscle cell similar to?

A

The skeletal muscle cells

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33
Q

What shapes are cardiac muscle cells? What are the ends called?

A

Y-shaped. The ends are called intercalated discs.

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34
Q

Are skeletal muscle cells or cardiac muscle cells longer?

A

Skeletal muscle cells.

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35
Q

What is between intercalated discs? Why is it beneficial? (2)

A

Gap junctions because it allows for rapid movement of ions and low electrical resistance.

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36
Q

What do gap junctions facilitate?

A

The wave of depolarization can pass easily from one cell to another.

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37
Q

Will the atria contract together? What causes the heart to contract?

A

Yes as one large cell. The heart contracts because of ions changing the charge in the cell.

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37
Q

What is a heart contraction called? What is it a result of?

A

A systole is the contraction and its a result of ions passing from the SA node through gap junctions to other atrial cells.

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38
Q

What type of signal is spread in the heart?

A

Electrical

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38
Q

Where is the atrioventrical node located? What is its purpose?

A

The atrioventrical node is located between the right atrium and the right ventrical and its purpose is to slow down the electricity so that the atria have time to empty before the ventricles contract.

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39
Q

Why are ions moving cell to cell in the ventricles not as efficient as in the atria?

A

Because the ventricles are much larger.

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40
Q

What structures allow for electricity to reach cells of the ventricles faster?

A

Bundle of His and Purkinje Fibres

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40
Q

What are the Bundle of His and Purkinje Fibres?

A

Special conducting fibres

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41
Q

Where does the contraction of the ventricles begin in the ventricles?

A

At the apex of the heart and pushes blood up towards the arteries.

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41
Q

What are some modifications in the Bundle of His (AV bundle) or the Purkinje Fibres?

A

Fewer myofibrils, bigger diameter. higher densities of voltage-gated sodium channels, higher densities of mitochondria/glycogen stores

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42
Q

What is another name for the Bundle of His?

A

AV bundles.

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42
Q

What monitors electrical signals through the heart?

A

ECG

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42
Q

Where are the Bundle of His located vs the Purkinje Fibres?

A

Bundle of His are located on the septum and the purkinje fibres are located on the edge of the ventricles

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43
Q

What is the P, QRS, T wave on the ECG wave?

A

P wave= electricity of the atrial contraction. QRS= electricity of the ventrical contraction. T wave= repolarization(recovery) where ions return to starting cell

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44
Q

Does the ventricle contract after the QRS wave or during?

A

After the wave

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45
Q

When does cardiac arrest occur?

A

When heart tissues are derived of oxygen.

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45
Q

What is ventrical fibrillation?

A

When the heart beats fast but the contractions are not strong.

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46
Q

What does a defibrillator do to the rhythm? What restores the normal heart rhythm?

A

Applies a shock to stop the abnormal rhythm. The SA node restores normal rhythm.

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47
Q

What is an artificial pacemaker?

A

Surgically fitted to replace a malfunctioning SA node.

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48
Q

What signals for the heart rate?

A

The medulla oblongata.

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49
Q

What type of nerves speed up the heart rate? Slow down?

A

Speed up=sympathetic nerves, Slow down= parasympathetic nerves

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50
Q

What is the formula for of cardiac output?

A

Cardiac output= heart rate x stroke volume

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51
Q

What is cardiac output? What are its unit?

A

The amont of blood bumped by each side of the heart per minute. ml/min are the units

52
Q

Is the amount of blood pumped by each side of the heart equal?

A

Yes, it will be equal.

53
Q

What is stroke volume?

A

Amount of blood forced out of the left ventricle on each beat?

54
Q

What is the average blood that is pumped out per beat?

A

70 ml per beat.

55
Q

Does a larger stroke volume indicate increased or decreased fitness?

A

Increased

55
Q

What is the average heart rate? Cardiac output?

A

Heart rate= 70bpm, Cardiac output= 4900ml/min

56
Q

What is the first heart “lub” sound indicating? During what time?

A

Closing of AV values during ventricular systole.

57
Q

What is the second heart “dub” sound indicating? During what time?

A

The closing of the semilunar valves during ventricular diastole.

58
Q

What does a heart murmuring indicate?

A

The backflow of blood caused by valve leakages in the heart.

58
Q

After what systole/diastole is a pulse felt?

A

After ventricular systole

58
Q

Are the atria and the ventricles ever at systole together?

A

No

58
Q

Are the atria and the ventricles ever at diastole together?

A

Yes, at the end of a heart beat.

59
Q

What is the ventricle doing when the AV valve is closed?

A

Ventricle systole

60
Q

What is the ventricle doing when the semilunar valves are closed?

A

Ventricular diastole.

61
Q

Will vasoconstriction lead to lower or higher blood pressure?

A

Higher Blood Pressure

62
Q

When does systolic blood pressure occur? Is it the higher number or lower?

A

Occurs during ventricular contraction/systole. It is the high number of the two phases.

63
Q

Is ventricular contraction systole or diastole?

A

Systole

64
Q

When does diastolic blood pressure occur?

A

During ventricular diastole, right before the ventricles contract again.

65
Q

What does a sphygmomanometer measure?

A

Blood Pressure

65
Q

When are arteries fully closed?

A

Right before systolic pressure.

66
Q

When are arteries fully open?

A

Right before diastolic pressure.

67
Q

What is the average blood pressure?

A

120mmHg/80mmHg

68
Q

In between systolic pressure and diastolic pressure, what is happening to the arteries?

A

They open/close with a pulse.

69
Q

What is high blood pressure called? What is the pressure reading usually?

A

Hypertension and is above 140mmHg/90mmHg

70
Q

What is the hardening of the arteries called?

A

Arteriosclerosis

71
Q

How can arteriosclerosis develop?

A

When there are high levels of cholesterol/lipids circulating.

72
Q

When the arteries are narrowed, what can result? Why?

A

Clots, a.k.a thrombosis because of the resuction of blood speed in the area.

73
Q

What happens when blood flow is cut off to the heart tissue? What about to the brain?

A

A heart attack. Brain stroke.

74
Q

What is the difference between atheroscelerosis and arteriosclerosis?

A

Atherosclerosis is a type of arteriosclerosis which occurs because of a buildup of lipids/cholesterol in the arteries. Arteriosclerosis just means hardening of the arteries.

74
Q

What did Galen think regarding blood?

A

It was created in the liver, then flowed to the heart and then to the lungs where it picked up “vital spirits”

75
Q

What hormone, if not present in high amounts, can lead to a higher risk of hypertension?

A

Estrogen

76
Q

What happens when an area of the arterial wall becomes weak and bulges (aneurysm)?

A

The arteries can burst and causes internal bleeding.

77
Q

Who came up with the modern model of the circulatory system?

A

William Harvey

78
Q

What pathways do antibiotics block? What type of cells do they act on?

A

Antibiotics block specific metabolic pathways in prokaryotic cells but not eukaryotic cells.

79
Q

Can you use antibiotics to treat viruses? Why or why not?

A

You can not use antibiotics as viruses do not have metabolic pathways. They are not living and use host cells.

80
Q

What is the HIV virus? What type of cells does it reduce?

A

It is an immunodeficiency disease. It reduces the helper T cell lymphocytes.

80
Q

What are lymphocytes?

A

A type of white blood cell.

80
Q

How does AIDS compare to HIV?

A

AIDS is the active disease that results from HIV. AIDS is the most serious stage of HIV.

81
Q

What percentage of blood is fluid? Cells?

A

55% of the blood is fluid, 45% of it is cells.

82
Q

What type of tissue is blood?

A

Connective tissue.

83
Q

What tool measures percentage of blood cells?

A

Hematocrit.

84
Q

What colour is plasma? What does it contain?

A

Plasma is yellowish and it contains proteins, vitamins, hormones, O2, CO2, waste products, heat, gluose, minerals, and blood cells.

85
Q

Why do red blood cells have a biconcave structure?

A

To increase surface area.

86
Q

Do red blood cells have a nucleus? What does that mean?

A

No nucleus which means they can’t divide.

87
Q

How many subunits does a heme group have?

A

4

88
Q

What makes blood red?

A

The heme group binding to oxygen to make oxyhemoglobin.

89
Q

Where are red blood cells produced? (2)

A

In the bone marow and spleen.

90
Q

What is the protein in hemoglobin called?

A

Globin

91
Q

What is the main role of the specific defense?

A

To produce antibodies.

92
Q

Do white blood cells have nuclei?

A

Yes.

93
Q

What is the main role of the non-specific defense?

A

To ingest pathogens.

94
Q

Do platelets have a nucleus? Why?

A

No, they do not as they are just cell fragments.

95
Q

What are platelets? Where are they produced?

A

Plates are thrombocytes that are produced in the bone marrow. They contain clotting factors to seal cuts.

96
Q

What type of cells in the bone marrow do platelets arise from?

A

Stem cells.

97
Q

How are platelets called to an injured vessel? What does the platelet initially do at the site?

A

Substances released by the injured vessel attracts the platelets. Platelets will rupture and release chemicals.

98
Q

When platelets rupture at the injured site, what do they combine with? (3) What does this produce?

A

Plasma proteins, vitamin K, and calcium. This produced thromboplastin.

99
Q

What does thromboplastin combine with when it is made? What does that result in?

A

Thromboplastin will combine with prothrombin (a plasma protein) to make thrombin

99
Q

What does thrombin activate? What does that result in?

A

Thrombin activates fibrinogen (plasma protein) and that makes fibrin.

100
Q

What forms mesh traps at an injured site to trap blood and form clots?

A

Fibrin

101
Q

What type of cells form a blood clot?

A

Red blood cells, white blood cells, and platelets.

102
Q

What is the lymphatic system a network of? (2)

A

Vessels and nodes

103
Q

What type of vessels ressemble lymphatic vessels?

A

Veins

104
Q

What is the fluid in the lymphatic system called? Where does the fluid start?

A

Lymph and that starts at the “dead-ends” of capillary beds.

105
Q

Where does the lymph get mixed with the blood?

A

At the veins near the heart.

105
Q

What is the lymphatic system typically called? Does it have a pump?

A

The second circulatory system and no it does not have a pump.

106
Q

What fluid forms the lymph?

A

Interstitial fluid surrounding the capillary beds.

107
Q

How are some fats transported in the body?

A

In the lymph.

108
Q

What type of white blood cells travel in the lymph?

A

Lymphocytes.

109
Q

Where do the lymphocytes mature?

A

In the lymph nodes.

109
Q

What does the lymph regulate? (2)

A

Fluid movement and balance.

110
Q

Where are the phagocytes found?

A

In the lymph nodes.

111
Q

What are some primary defense barriers of the immune response?

A

Eyelashes, cilia, stomach acid and skin, mucous

112
Q

Why do lymph nodes swell?

A

If body needs to mount immune response, glands may swell because white blood cells will divide.

113
Q

What makes the skin inhospitable for pathogens? (4)

A

Dry, tough outer covering (keratin), oil containing bacteriocides, perspiration makes the skin acidic

113
Q

Is the secondary immune response specific?

A

No.

114
Q

What do white blood cells release to dilate blood vessels and make them more permeable to other white blood cells? What immune response is this part of?

A

Histamine, part of the secondary response.

115
Q

What type of white blood cells eat invading pathogens?

A

Phagocytes

116
Q

When does the tertiary immune response begin?

A

When the pathogen is killed and a piece of it becomes an antigen.

117
Q

What do helper T cells do? (2)

A

They recognize the presence of a foreign antigen and they signal a B-cell lymphocyte called a plasma cell to produce antibodies for that antigen.

117
Q

How does the helper t-cell signal the b-cells to replicate?

A

They bind to plasma cells to signal more plasma cell production and memory B-cells.

118
Q

What are antigens?

A

Specific glycoproteins on the surface of cells.

119
Q

Where do plasma B-cells mature? Where are they produced?

A

In the spleen and lymph nodes. They are produced in the bone marrow.

119
Q

Is the thymus pat of the lymphatic system? What matures here?

A

Yes, helper T-cells mature here.

119
Q

What are the three roles of antibodies?

A

They stick to antigens to make them “stick together”, they neutralize harmful areas of a pathogen, they help tag foreign cells for the immune system.

120
Q

What are killer T-cells?

A

These are the cells that kill cancer cells and cells infected wuth viruses. They can also reject an organ.

121
Q

What type of cells are responsible for immunity? (2)

A

Memory B and T cells.

122
Q

What is the role of suppresor T cells?

A

They decrease the immune response so as to save energy and resources for the next response.

123
Q

Why do allergies get worse the more you are exposed to them?

A

The memory B/T cells make for a stronger immune response.

123
Q

What are auto-immune diseases? What can cause them?

A

An overactive immune system that can be caused by a lack of suppressor T-cells.

124
Q

How is the immune response like the second time an antigen is experienced?

A

The second response is faster and generates a higher level of antibodies.

124
Q

What do vaccines contain? What do those do?

A

Vaccines contain antigens that trigger immunity but do not cause the disease.

125
Q

What type of cells do vaccines make?

A

Memory cells.

125
Q

What type of blood has A antigens? B antigens? Both?

A

Type A, type B, type AB

125
Q

What type of blood has no surface antigens?

A

Blood type O.

126
Q

What will happen if your a type A blood that got donated type b blood? What will the end result be called?

A

Your body will see the type b antigens as foriegn and will produce antibodies that will cause clumping of RBCS. This is called agglutination.

127
Q

What are those with the Rh factor reffered to as?

A

Rh positive

128
Q

Can an Rh+ individual donate to an Rh- individual?

A

No.

129
Q

How do you prevent the mother from producing Rh+ antibodies against her own child? What does this destroy?

A

Inject the mother with anti-Rh antibodies so they can destroy the baby’s cell in her system before her immune system reacts.

130
Q

Why can it be dangerous for an Rh- mother to give birth to a Rh+ baby?

A

The Rh+ baby’s blood may cross into the mother’s body which will cause teh mother to produce antibodies against the Rh+ antigen. This can be dangerous for second Rh+ pregnancies since the mother’s antibodies can destroy baby’s blood.

131
Q

What did Alexandra Fleming discover?

A

Antibiotics, specifically Penicillium notatum.

132
Q

What are viruses made of?

A

Protein coat surrounding genetic material.

133
Q

Why can a vaccine not be created for the HIV virus?

A

The virus mutates often, changes surface antigens, so it is hard to make a vaccine.

133
Q

Why can viruses not reproduce?

A

They contain either DNA or RNA but never both so they can not reprodue.

134
Q

When body is too warm, will blood vessels dilate or constrict? What is this called?

A

Blood vessels will dilate. This is called vasodilation.

135
Q

If blood pressure is too high, will vasodilation or vasoconstriction result?

A

Vasodilation.

136
Q

What are many capillaries in an area called?

A

A capillary bed.

136
Q

If blood pressure is too low, will blood vessels dilate or constrict?

A

Constrict.

137
Q

What an capillaries do to reduce blood flow in an area if blood is not needed there?

A

Turn off their sphincters.

Bio 20 IB (6 decks)

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