Structures and Functions of the Circulatory System Flashcards
1
Q
What are the functions of the Circulatory System?
A
- Transports gasses and wastes
- Regulates internal temp, transports hormones
- Protects against blood loss from injury (platelets), provides immune response
2
Q
The 3 major components of the Circulatory System are..
A
- Heart
- Blood Vessels
- Blood
3
Q
Pumps blood through body, generates blood flow
A
Heart
4
Q
- “Roadways” for blood
- Arteries, veins, and capillaries
A
Blood Vessels
5
Q
Carries nutrients, O2, CO2, wastes, and other materials throughout the body.
A
Blood
6
Q
Where is the heart located?
A
Slightly left of middle of chest
7
Q
Two chambers at the top of the heart
A
Atria (singular = Atrium)
8
Q
Two chambers at the bottom of the heart
A
Ventricles
9
Q
Thick muscular wall that separates the heart from the middle
A
Septum
10
Q
Fluid filled membrane surrounding the heart
A
Pericardium
11
Q
Separates atria from ventricles
A
Atrioventricular (AV) Valves
12
Q
Separates ventricles from arteries
A
Semilunar Valves
13
Q
Why does the heart have one-way valves between atria, ventricles, aorta, and pulmonary arteries?
A
To ensure blood flows in the correct direction. (one direction)
14
Q
What is deoxygenated blood?
A
- Shown on diagrams as blue (to separate from oxygenated blood)
- Blood returning from tissues
- Low O2 content (because its just delivered all its O2 to the tissues)
- Heading towards the heart & lungs to get more oxygen
15
Q
What is Oxygenated blood?
A
- Blood leaving the lungs filled with O2
- Heading towards tissues to deliver O2
16
Q
- O2 poor blood coming back from the body is pumped through the VENA CAVA (right side of heart) into the..
A
Right Atrium
17
Q
- Blood flows from RIGHT ATRIUM to RIGHT VENTRICLE and then out the LEFT AND RIGHT…
A
Pulmonary ARTERIES
18
Q
Pulmonary ARTERIES lead to the..
A
Lungs (for gas exchange)
19
Q
- O2 rich blood from the LUNGS returns to the heart through LEFT AND RIGHT..
A
Pulmonary VEINS
20
Q
- O2 rich blood enters the LEFT ATRIUM then the..
A
LEFT Ventricle
21
Q
- O2 rich blood leaves the heart through the…
A
AORTA
22
Q
The Aorta leads to..
A
the whole body
23
Q
- Carries blood AWAY from the heart
- Highly Elastic walls
A
Arteries
24
Q
DEOXYGENATED blood leaves the right side of the heart to the lungs via..
A
Pulmonary ARTERIES
25
OXYGENATED blood leaves the left side of the heart via..
AORTA
26
- Smallest blood vessels
- Walls are a single layer of cells
Capillaries
27
Site of gas, nutrient and waste exchange between blood and cells
Capillaries
28
- Carries blood TOWARDS the heart
- Not elastic, cannot contract to move blood back to the heart
- Relies on contraction from surrounding skeletal muscle
Veins
29
Has thinner walls than Arteries
Veins
30
Contains one-way valves to prevent back flow against gravity
Veins (unlike Arteries/except Arteries exiting the ventricles)
31
Deoxygenated blood returns to the RIGHT side of the heart via..
Vena Cava
32
Oxygenated blood returns to the LEFT side of the heart via..
Pulmonary Veins
33
Occurs when the leaflets of valves fail to close properly, causing blood to flow backwards and pool in the veins
Varicose Veins
34
Biggest Artery
Aorta
35
Small Arteries
Arterioles
36
Small Veins
Venuoles
37
The stimulus that triggers a heartbeat
An Electrical Signal
38
- Bundle of specialized nerves and muscle tissues.
- Acts as a pacemaker -sets rate of heartbeat (70bpm)-
Sinoatrial Node (SA Node)
39
Where is the SA Node located?
The wall of the right atrium.
40
Generates electrical signal that spreads over the two atria and them contract simultaneously
SA Node
41
Where is the AV Node located?
The bottom of the right atrium.
42
- Receives electrical signals from the SA Node
- Left and Right Ventricles contract simultaneously
Atrioventricular Node (AV Node)
43
AV Node transmits signal through the..
Bundle of His (Bundle of specialized nerve fibers)
44
The fibers in the AV Node relay signal through two branches of conducting fibers called..
Purkinjie Fibers
45
A device that records the electrical activity of the heart as it contracts and relaxes
Electrocardiogram (ECG)
46
What is the Electrocardiogram used for?
To diagnose certain heart problems. (looking at the graph and analyzing any abnormal line tracings).
47
Refers to heart relaxation (heart fills with blood)
Diastole
48
Refers to heart contraction (heart pumping blood out)
Systole
49
Sound produced when AV valves close. (When ventricles contract, blood is forced up and cause the AV valves to close).
Lubb
50
Sound produced when the Semi-lunar valves close
Dubb
51
What does the ECG wave part "P" mean?
Just before atrial contraction.
52
What does the ECG wave part "QRS" mean?
Electrical impulse that spreads through ventricles (ventricle contraction).
53
What does the ECG wave part "T" mean?
Ventricles recovering before next SA stimulation. (Atrial relaxation recovery/heart filling).
54
Where is the lubb sound heard on the ECG chart?
P to Q
55
Where is the dubb sound heard on the ECG chart?
S to T
56
What are the two measurements of blood pressure?
Systolic and Diastolic
57
Top, 120, Ventricles contract
Systolic
58
Bottom, 80, Ventricles relax
Diastolic
59
Pressure blood exerts during ventricular contraction.
Systolic blood pressure
60
Pressure blood exerts during Ventricular relaxation
Diastolic blood pressure
61
Amount of blood flowing from the heart each minute
Cardiac output
62
The quantity of blood pumped with each heartbeat (~70mL/beat)
Stroke Volume
63
Number of heart beats per minute (~70 beats per minute)
Heart Rate
64
When Cardiac Output is increased, is blood flow increased or decreased?
Increased
65
When Cardiac Output is decreased, is blood flow increased or decreased?
decreased
66
What are factors affecting cardiac output?
1. Size of Individual
~Large mass = higher cardiac output Smaller mass = smaller cardiac output
2. Exercise
67
Vessels that carry blood to and from the lungs.
Pulmonary Circulation
68
Vessels that carry blood to and from the body.
Systemic Circulation
69
The heart's separate blood supply that supplies cardiac muscles with O2 and other nutrients.
Coronary Pathway
70
Condition where there is a buildup of plaque (fatty deposits, calcium, and fibrous tissues) inside of the artery walls.
Narrowing = higher pressure which leads to angina, blood clots, shortness of breath, heart attack, and heart failure.
Atherosclerosis
71
How is Atherosclerosis treated?
1. Aspirin - reduce formation of clots
2. Clot busting medication
3. Angioplasty (balloon inserted)
4. Stent (permanent metal tube)
5. Coronary bypass surgery (healthy artery creates a new pathway).
72
- Congenital (born with)
- Misflow of blood in the heart
- Valves not opening or closing properly
~Valve defects can be heard with a stethoscope
- Problems in the walls of the chambers.
Heart Murmur
73
- High blood pressure: causes blood vessels to weaken or even rupture
- Results in build-up of connective tissue as body tries to repair, making arteries hard and less elastic
Hypertension
74
- Low blood pressure: reduces bodies ability to transport blood
- Problem for your brain because blood pressure has to work against the force of gravity to get up there
= dizzy spells
Hypotension
75
What is the relative velocity (speed) of the blood as it flows through the capillaries?
Slowest (single-file and time for gas exchange).
76
What happens to blood pressure as blood moves from the arteries to the veins?
The blood pressure lowers.
77
Why does the pressure change as blood moves from the arteries to the veins?
Arteries have muscular walls (higher pressure), Veins don't have muscular walls.
78
What circulatory system organ is responsible for supplying the pressure for the blood?
The Heart
79
Which chambers are pumping chambers of the heart?
Atriums
80
Which chambers are the receiving chambers of the heart?
Ventricles
81
How do the walls of the atria compare with the walls of the ventricles and why are they different?
The walls of the atria are thinner than the ventricles because the ventricles use more power to pump blood throughout the body.
82
What is the purpose of heart valves?
So the blood doesn't flow backwards (backflow).
83
Which artery is the largest and why?
The aorta because it carries O2 blood throughout the body.
84
Above what value is someone considered to have high blood pressure?
From a130/80 mm Hg or higher
85
From a medical perspective, what is the problem with having high blood pressure?
The chance of having a heart attack, and stroke are increased.
86
Below what value is someone considered to have a low blood pressure?
From 90/60 mm Hg or lower
87
From a medical perspective, what is the problem with having low blood pressure?
Some potential problems include dizziness, weakness, and fainting.
