Ch. 8 - Heart/Circulation Flashcards
(141 cards)
1
Q
What are the functions of the circulatory system? General.
A
Transport, Regulation, Prevention, Protection
2
Q
What does the circulatory system transport?
A
- Gases
- Nutrients
- Waste Materials
- Hormones
3
Q
What does the circulatory system regulate?
A
Internal temperatures
4
Q
What does the circulatory system prevent?
A
Blood loss
5
Q
What does the circulatory system protect?
A
- Disease causing microbes
- Toxic substances
6
Q
The circulatory system can only function in what? What is the term for this?
A
A closed system, or closed circulation.
7
Q
What is closed circulation?
A
Blood never leaves vessels.
8
Q
The circulatory system is considered a what? What is the term for this?
A
A double system, or double circulatory system.
9
Q
What is a double circulatory system? What are the two systems classified as?
A
In mammals, birds, and reptiles…
The blood is pumped twice before returning to its origin.
1. Pulmonary Circulatory System
2. Systemic Circulatory System
In fish and other lower animals, this happens only once.
10
Q
What is a pulmonary circulatory system?
A
Relating to the lungs.
Between the heart and lungs
11
Q
What is a systemic circulatory system?
A
Between the heart and body.
12
Q
What are the three major components of the circulatory system?
A
- Heart
- Blood Vessels
- Blood
13
Q
Which parts of the heart are pulmonary?
A
- L/R pulmonary arteries
- L/R pulmonary veins
- L pulmonary trunk
14
Q
Which parts of the heart are systemic?
A
- Superior/Inferior Vena Cava
- Aorta (top and bottom)
15
Q
Which parts of the heart are actually structures?
A
- Right Atrium
- Right Ventricle
- Left Atrium
- Left Ventricle
- (Apex)
16
Q
Which stuctures of the heart are vessels?
A
- L/R pulmonary arteries
- L/R pulmonary veins
- L pulmonary trunk
- Superior/Inferior Vena Cava
- Aorta (top and bottom)
17
Q
What are the heart’s 3 major functions? Which structures performs this?
A
- Pumping blood through the body (ventricles)
- Keeping oxygen rich blood seperate from oxygen poor blood (septum)
- Ensuring that blood flows only in one direction through the body (valves)
18
Q
What is the pericardium?
A
Membrane surrounding the heart which prevents friction between heart and lungs.
19
Q
What does the pericardium do?
A
Helps isolate infection.
20
Q
What is the heart made of?
A
The walls of the heart are made up of specialized cardiac muscle tissue found nowhere else in the body.
21
Q
How many chambers does the heart have?
A
All mammals and birds have 4 chambered hearts.
2 ventricles, 2 atria.
22
Q
What do the atria do and where are they located?
A
The atria is the two top chambers and they recieve blood.
The right gets from the body.
The left gets from the lungs.
23
Q
What do the ventricles do and where are they located?
A
The ventricles are the bottom to chambers and recieve blood from the atria.
They are much larger and muscular than atria.
The right pumps to the lungs.
The left pumps to the whole body.
24
Q
What is the colouring of blood in corrolation to oxygen levels?
A
Dark red: deoxygenated
Light red: oxygenated
25
What does the septum do?
Is a thick muscular wall that seperates the left and right sides of the heart.
26
What is the path of blood through the body?
RIGHT SIDE: deoxygenated from body and pumps it into the lungs
1. From superior vena cava and inferior vena cava
2. Into the right atrium
3. Through the tricuspid valve
4. Into the right ventricle
5. Through the pulmonary semilunar valve
6. Out the pulmonary trunk, splitting into the pulmonary arteries, to lungs to remove waste and get O2
LEFT SIDE: getting oxygenated blood from the lungs
1. From pulmonary veins
2. Into the left atrium
3. Through the bicuspid valve
4. Into the left ventricle
5. Through the aortic semilunar valve
6. Out the aorta, to the body, where it becomes deoxygenated again
27
The right side of the heart recieves __ from the __ and pumps it back to the lungs.
Deoxygenated blood
Body
28
What do the vena cavae do? Where do they open into?
They open up into the right atrium.
The superior vena cava collects oxygen-poor blood from the head, chest, and arms (above the heart).
The inferior vena cava collects oxygen-poor blood from the rest of the body.
29
What do the pulmonary arteries do?
Gas exchange. The only arteries in the body that contain deoxygenated blood.
30
The left side of the heart recieves __ __ from the lungs and pumprs it out to the body.
Oxygen-rich blood
31
What does the aorta do? Where does it go to?
Blood's pumped from the left atrium to the left ventricle and out to the body through the largest vessel in the body: the Aorta.
It is of oxygen-rich blood.
32
What do the pulmonary veins do?
Oxygen-rich blood flows from the lungs through the pulmonary veins into the left atrium. The only veins in the body that contain oxygenated blood.
33
Which side of the heart is stronger?
The left side is bigger and more muscular.
34
What are the four valves of the heart? What are they divided into?
- Atrioventicular valves
- Semilunar valves
35
What are the role of atrioventricular valves? For what?
One way valves that seperates the atria and the ventricles.
**In heart.**
36
What is the role of chordae tendinae?
(Tendon chords, which hold the bicuspid and tricuspid valve are held by)
Ensure blood is not pushed back into the atria during ventricular contraction.
Support valves.
37
What are the two atrioventricular valve called? Which side is each on and how many flaps does each have?
- Bicuspid (Mitral) Valve, left side, two flaps
- Tricuspid Valve, right side, three flaps
38
What are the role of semilunar valves?
At the entrance of the major arteries, pulmonary arteries/aorta, are smaller valves with no muscular attachment.
**Out heart.**
39
What are the two semilunar valves called? Which side is each on and how many flaps does each have? For what?
- Pulmonary semilunar valve in pulmonary artery (on the right side)
- Aortic semilunar valve in aorta (on the left side)
Has three flaps each to prevent backflow into ventricles.
40
Blood flows out of the heart through the aorta, into blood vessels. Where is the first blood vessel it flows to?
Arteries
41
More muscle = __ valves (in the context of arteries and veins)
Arteries don't require valves because pressure from the heart is so strong that blood is only able to flow in one direction.
So, more muscle = less valves
42
What are arteries?
Carry blood away from the heart, usually oxygen-rich blood, with the exception of the pulmonary artery.
- Have thick walls with muscles that allow them to change in diameter
- Have the greatest pressure and are found deep within the body tissues
- Pulse can be felt in arteries because the blood travels in spurts as the heart contracts
- No valves
The largest artery: aorta.
43
What are arterioles?
Small arteries which lead into capillaries. They have muscles called precapillary sphincters, which can open or close and thus, regulate the flow of blood into the capillaries.
44
What are vasodilators? (from the blood vessels page)
Chemicals/nerves that cause artery smooth muscles to dilate (expand).
45
What are vasoconstrictors? (from the blood vessels page)
Chemicals/nerves that cause arteries/arterioles (smooth muscles) (and maybe precapillary sphincter) muscles to constrict (shrink).
46
What are capillaries?
The smallest blood vesssels. 10 bundled together would have the diameter of a human hair.
- The walls are only one cell thick, allowing materials to **diffuse through to tissues.**
- Are under low pressure and blood moves very slowly (often one cell at a time)
47
What are venules?
Capillaries merge and become larger vessels (like arterioles). No precapillary sphincters, but contain smooth muscle and valves.
48
What are veins? What muscle do they contain? How about their pressure? What else do they have that arteries don't? How is blood moved?
Always carry blood to the heart (usually oxygen-poor blood, except the pulmonary vein).
- Contain smooth muscle.
- Have the least pressure.
- Have one-way valves that prevent blood from flowing backwards, especially important in the legs where blood must flow up against the flow of gravity.
- Blood is moved through veins by suction from the heart and the action of the muscles found around the veins.
49
What is the 6-step process of the beating heart? Which parts/processes?
1. Sinoatrial node initation
2. Stimulation through electric impulses
3. Atria contraction
4. Reaches Atrioventricular node, transmitting signal through specialized fibers called HIS
5. Travels through HIS, divding into two branches, fast conducting purkinje fibers
6. Impulse contracts ventricles
50
Where is the heart beat initiated? By what?
By specialized tissue called the sinoatrial node (aka the pace maker).
In the right atrium.
51
The sinoatrial node sends out impulses which __.
Stimulate the heart muscles in atria to contract.
52
The SA node's electrical signal causes what to contract?
The two atria contracts simultaneously.
53
As the atria contracts and reaches the __ __, a new signal transmits through __.
The AV node, that transmits the signal through specialized fibers called the bundle of HIS.
54
What does the bundle of HIS divide into to transmit signals?
Purkinje fibers, that are fast conducting, and are two bundle branches
55
What happens as the signal reaches the purkinje fibers?
The ventricles contract (push against septum).
56
The heart beat is a cycle. What does this mean?
It's lubb-dubb. It's a two step process: the systole and diastole, and repeats.
57
What is systole?
**Contraction**
The ventricles contract, and the atrioventricular valves close, which makes the "lubb" sound.
58
What is diastole?
**Relaxation**
The atria drains into the ventricles, and the semi lunar valves close, which make the "dubb" sound.
59
What are the four factors that are important to humans, measured, and should be controlled?
- Heart Rate
- Blood Pressure
- Constant temperatures
- Cardiac Output/Stroke Volume
60
What is the heart rate set by?
Sinoatrial Node
61
What is a normal heart rate?
80 beats/min
62
What is bradycardia?
Not enough blood. <50 beats/min
63
What is tachycardia?
Lots of stress on heart. >100 beats/min
64
Heart rate is regulated by a feedback system which includes? Explain each briefly.
Monitor: detects change
Control center: sends out orders
Regulator: brings about a change
65
Why do athletes have a lower heart rate?
Their heart is often more efficient.
66
What is the control of heart rate determined by?
The levels of CO2 in the blood.
67
What happens if CO2 levels increase?
Chemoreceptors in the carotoid arteries and aorta (the monitor) detect this change, and send a message to:
The medulla oblongata (control center) which sends out:
Sympathetic nerve impulses (the regulator) to the heart causing it to beat faster. ("fight or flight")
68
What is the medulla oblongata?
The brain stem, performs automatic functions, that send out nerve impulses.
69
What happens if there is a too high CO2 level?
Blood becomes more acidic.
70
What are chemoreceptors and where are they?
In carotid arteries and aorta (the monitor) to detect higher CO2 levels.
71
What happens if CO2 levels drop?
Chemoreceptors in the carotid arteries and aorta (the monitor) detect this change and send a nerve message to:
The medulla oblongata (control center), which sends out:
Parasympathetic impulses, causing the heart rate to drop (rest and digest).
72
Which two regulatory nerves influence the sinoatrial node? Functions of each to heart rate and blood pressure.
Sympathetic nerves: increase heart rate, arteriole constriction = higher pressure (fight or flight)
Parasympathetic nerves: slow heart rate, arteriole dilation = lowered pressure (rest and digest)
73
What things can influence heart rate? Describe each briefly.
- Ephinephrine/adrenaline (a hormone released in times of stress) increase heart rate
- Increased body temperature = increased heart rate to dissipate heat, vice versa
- Many chemiacls, such as carbon monoxide, alcohol, nicotine (stimulants) can also affect heart rate (increase)
74
What is an electrocardiogram (ECG/EKG)?
Used to measure the change in voltage produced as the heart contracts and relaxes.
75
What are the three waves and complexes of the electrocardiogram diagram? What happens at each state
P wave - represents the small voltage increase before atrial contraction (SA node); small bump; diastole
QRS complex - spike in electrical activity just before ventricular contraction (AV node); large spike; systole
T wave - small spike in electrical activity as ventricles relax; small bump
76
Why can't the relaxation of the __ be measured?
Atria; it takes place at the same time as ventricular contraction.
77
What is blood pressure?
Measure of the force that blood exerts against blood vessel walls as it's pumpsed from the left ventricle.
78
What is blood pressure measured in, and what is used?
Sphygomomanometer in mm of mercury (1 mmHg = 0.133kPa)
79
What causes pressure to increase in the aorta and pulmonary arteries?
When ventricles contract, it forces blood into aorta and pulmonary arteries, pressure increase.
80
What causes pressure to drop in blood vessels?
Ventricular relaxation
81
When is blood pressure the highest?
Systolic pressure (force generated by the ventricles)
82
When is blood pressure the lowest?
Diastolic pressure (resistance created by walls of arties)
83
Systolic pressure is given over diastolic pressure in the form of a:
Fraction
84
The average blood pressure of a healthy young person is:
120 (systolic) / 80 (diastolic)
85
Is systolic or diastolic pressure worse to be high?
Diastolic, because it's not supposed to be very high at all?
86
As heart rate increase more blood is pumped per unit time and pressure within the arteries:
Increase
87
What are the 5 factors that affect blood pressure?
- Volume of blood
- Heart rate
- Size of arteries (diameter)
- Ealsticity of arteries
- Viscosity of blood
88
How does the volume of blood affect blood pressure?
Less blood bolume (often cause of injuries) means lower blood pressure
89
How does heart rate affect blood pressure?
Increased heart rate, means higher blood pressure, as the heart beats with more force
90
How does the size (diameter) of arteries affect blood pressure?
Greater diameter, means less pressure, as there is more room for blood to flow
91
How does the elasticity of arteries affect blood pressure?
Less elasticity, often due to age, or atherosclerosis (plaque build up) causes increased blood pressureH
92
How does the viscosity of blood affect blood pressure?
- Thick fluid means less easy to move, increasing blood pressure
- More blood cells to plasma ratio will make blood thicker so DRINK WATER
93
What are vasodilators? (from the blood pressure page)
Chemicals that cause arteries smooth muscle to dilate.
Ex: CO2, histamines
94
What are vasoconstrictors? (from the blood vessels page)
Chemicals that cause arteries smooth muscle to constrict
Ex: Angiotensin II, antihistamine
95
How is high blood pressure regulated by the body? What does this result in?
Monitors called baroreceptors, in the aorta and carotid arteries, are sensitive to high blood pressure.
High BP causes these receptors to send a message to the medulla oblongata, which sends out more parasympathetic nerve impulses and less sympathetic ones.
Results in arteriole dilation - reduced cardiac output. More space = flow easier.
96
What are baroreceptors?
Monitors located in the aorta and carotid arteries are sensitive to high blood pressure.
97
How is low blood pressure regulated by the body? What does this result in?
The kidney (needs higher BP as it filters blood), which monitors BP, will produce renin if BP drops and is released into the blood.
Rennin causes the chemical angiotensin II to be produced in the blood, causing arteries to constrict and some capillary beds to shut down.
This is an attempt and results in increased pressure by reducing the space blood has to occupy.
98
What is hypertension?
When systolic pressure is over 140 (resting: 120) or diastole pressure is over 90 (resting: 80).
Causes blood to work harder, the heart becomes enlarged and less efficient, and potentially a heart attack. It also may cause a stroke.
99
What is a stroke?
Ruptured blood vessel in the brain.
100
What is a heart attack?
A coronary artery that's blocked can't bring oxygen to your heart muscles.
101
What can hypertension be caused by? (4)
- Atherosclerosis (plaque and hardening build-up in blood vessels, narrow tube)
- Genetics
- Impaired kidney function (fluid retention)
- Stress (causing narrow blood vessels and increased heart rate)
102
What is homeostatic regulation? Why is there __ produced?
The body must maintain a constant temperature for metabolic processes to function.
Heat is produced during cellular respiration and muscular activity. The heat is transported by the blood.
103
How is heat lost in the body?
As warm blood from the interior of the body passes by the skin, heat is lost from the body.
The greater the heat gradient, the greater the heat loss.
104
How does the body respond when the body's temperature becomes too warm?
Blood vessels dilate/expand to increase blood flow and therefore heat loss through skin (vasodilation)
105
How does the body respond when the body's temperature becomes too cold?
Blood vessels near the surface of the skin contract reducing blood flow and heat loss (vasoconstriction).
106
When and what does shivering happen and do?
Waves of muscle contractions (shivering) increase heat production by cellular metabolism. The heat spreads through the blood.
Happens when cold.
107
How do vasodilation and vasoconstriction control blood pressure and temperature?
If blood pressure is too high:
vasodilation reduces it
If blood pressure is too low:
vasoconstriction increases it
108
Increased metabolic activity (first what is this) increases _. This is a _ reaction.
Eating/digestion: Vasodilation, Exothermic
109
Nicotine, carbon dioxide, and alcohol promote __ and cause blood to rush to the skin.
Depends where and stimulants and stimulants have different reactions.
But to this, vasodilation.
110
What type of system helps the body to maintain a steady core body temperature under normal conditions?
A concurrent exchange system, as deep arteries are warmer and move faster, compared to surface veins.
(The countercurrent heat exchange mechanism between the blood vessels in the human arm: The deep vein and artery are adjacent to one another, so heat is exchanged from one to the other. As a result, arterial blood is cooled as it nears the hand, and venous blood is warmed as it leaves the hand and returns to the body core. When heat conservation is important, more blood returns to the heart through the deep vein. In higher-temperature conditions, when heat conservation is not a concern, more blood returns through the surface vein.)
111
What are the three types of major vessels in the arm, part of the concurrent exchange system?
Deep artery, deep vein, surface vein
112
What is cardiac output?
Amount of blood pumped out from the heart each minute, measured in mL/min.
(Cardiac output is the total volume of blood pumped by the ventricle in a minute. )
113
What two factors affect cardiac output?
Heart rate, stroke volume
114
What is stroke volume?
Amount of blood forced out of the heart with each heartbeat.
How easily the heart fills with blood and empties.
(Stroke volume is the amount of blood pumped by the left ventricle of the heart in one contraction.)
115
How is cardiac output calculated?
Stroke volume x Heart rate
116
Concerning stroke volume, how easily the heart fills is related to:
The volume of blood returning to the heart from veins AND stretchiness of ventricles.
117
Concerning stroke volume, how easily the heart empties is related to:
Strength of ventricular contraction AND pressure exerted by artery walls.
118
What is the average stroke volume, resting heart rate, and cardiac output for a person?
70mL, 70 bpm, for 4900mL/min
119
How much blood does the regular person have?
5L, so almost all your blood is filtered through in a minute.
120
What does a lower resting heart rate mean?
Cardiovascular fitness because stroke volume is high
121
How does cardio impact heart health?
It enlarges the ventricular chambers, increases the flexibility of the ventricles, and strengthens the ventricle walls.
122
How does strength training impact heart health?
Strength training increases the thickness of the walls, which might limit stroke volume by reducing the elasticity of the ventricles.
123
Blood is carried along three different pathways throughout the body. Which three?
- Pulmonary (heart/lungs)
- Systemic (heart/body)
- Coronary (heart/heart)
124
What is the coronary pathway and why is it important?
The heart cannot use the blood inside its chambers to get nutrients and oxygen or remove wastes.
125
What are the three components in the coronary pathway?
1. Capillaries are embedded in the heart walls which receive blood from two coronary arteries that split off from the aorta
2. Arteries branch into smaller and smaller blood vessels so that a network of tiny blood vessels covers the heart
3. Oxygen-poor blood leaves the heart through the coronary veins and into the right ventricles where it's pumped out into the lungs.
126
What is the main function of the coronary pathway?
To supply heart muscle with blood AND to remove wastes
127
What are the main cardiovascular disorders and treatments? Why is this significant?
Atherosclerosis -> Angina
- Angioplasty
- Coronary Bypass
(Atherosclerosis causes many of these)
Heart Murmurs
Aneurysm
Varicose Veins
(Artificial pacemakers)
The leading cause of death in Canadians is cardiovascular disease.
128
What is atherosclerosis? Potential implications and what may this lead to?
The general term is used to describe the thickening and hardening of the arteries. Often a silent killer.
Fatty deposits of calcium, and fibrous tissue form a plaque on the inside of arteries/blood.
Less diameter, stretch, blood flow, and increased blood pressure.
May lead to angina.
129
What is angina?
Chest pain, reduced blood flow.
- blood clots
- shortness of breath
- heart attack
- heart failutre
130
What are some ways to reduce developing atherosclerosis?
- Not smoking
- Lots of fruits/veggies
- Less saturated fats
131
What are some treatments for atherosclerosis?
- Angioplasty
- Coronary Bypass
132
What is angioplasty?
- Surgeon inserts tube into clogged artery
- Balloon inflates artery at the clogged site
- Sometimes a small metal tube is inserted to hold vessel open, preventing further blockage.
133
What is a coronary bypass? Why is it often a last resort?
- Uses a healthy segment of the artery/vein (often in the leg) to create a new pathway around a blood vessel near the heart.
- One end of the new segment attaches to aorta, other beyond a point on the vessel beyond the blocked part
- Double/Triple/Quad. is used to describe how many vessels with blocks need to be passed
The heart needs to be stopped.
134
What are heart murmurs?
- Relatively common heart defect: misflow of blood through the heart
- One or more valves don't open/close properly
- Can be heard through a stethoscope
- "Whoosh" sound when blood leaks through valve
*Lubb, dubb, whoosh*
Can be either congenital or acquired.
Less flow out of the aorta, decreasing blood pressure. Blood may backflow into lungs, which increase blood pressure in those pulmonary vessels.
135
What is it called when one has a condition from birth?
Congenital
136
What is it called when one gets a condition later in life?
Acquired
137
What is an aneurysm?
With-blockage.
A fluid-filled bulge is found in the weakened wall of an artery.
Very bad if in the heart/brain.
138
What are varicose veins?
Veins which valves do not close properly. Blood clots/pools in the veins, usually in the legs.
139
What are artificial pacemakers? What are some limitations of it?
Use batteries to produce a coordinated signal when the "real" pacemaker malfunctions.
Only allows for a consistent heart rate, as a result, hard to exercise or even be stressed. Can't be elevated.
140
Define Homeostatic Regulation?
Steady internal conditions.
141
The pressure forcing fluid out of the arteriolar end of a capillary network is referred to as __. The force that causes the water to return to the blood vessel at the other end is _. The osmotic gradient between the blood and the ECF is due primarily to large molecules called _ and the dissolved minerals in the blood.
hydrostatic pressure, osmotic pressure, albumins
