Cardiovascular System Flashcards
1
Q
what is the cardiovascular system responsible for?
A
transportation of nutrients, oxygen, hormones, and waste products to and from cells
2
Q
what is the cardiovascular system made up of?
A
- the heart, blood vessels and blood
3
Q
The heart
A
- muscular organ located in chest cavity slightly to the left of midline
- divided into 4 chambers: 2 atria (upper chambers) and 2 ventricles (lower chambers)
- right side receives DEoxygenated blood from body and pumps it to the lungs for oxygenation
left side receives OXYGENATED blood from lungs and pumps it to the rest of the body - encased in a protective sac called pericardium and is supplied with its own blood vessels (coronary arteries)
4
Q
Arteries
A
- blood vessels that carry oxygenated blood AWAY from the heart to various parts of the body, they have thick
- muscular walls to withstand high pressure generated by the heart-pumping action
- aorta (largest artery) branches into smaller arteries then into arterioles
- thick muscular walls of arteries allow them to withstand the high pressure generated by the hearts contractions
- macrocirculation
5
Q
Veins
A
- blood vessels that carry deoxygenated blood BACK to the heart from the body’s tissues
- veins have thinner walls and contain valves to prevent backflow of blood
- veins have valves that prevent baackflow of blood (ensuring that it moves in one direction towards the heart)
- largest veins (superior and inferior vena cava) empty directly into hearts right atrium
- macrocirculation
6
Q
capillaries
A
- microscopic blood vessels where the exchange of oxygen, nutrients, and waste products occurs between blood and body tissues
- mostly part of microcirculation but are bridge between arteries and veins
7
Q
what is the circulatory system responsible for?
A
- transportation of blood, oxygen, nutrients, and waste products to and from cells
8
Q
what are the two major components of the circulatory system?
A
- macrocirculation
- microcirculation
9
Q
Macrocirculation definition
A
- refers to the movement of blood through the larger blood vessels
- names arteries and veins
10
Q
responsibility of macrocirculation
A
- transporting blood over longer distances within the body
- ensures organs and tissues receive an adequate amount of oxygenated blood and that deoxygenated blood is returned to the heart for reoxygenation
11
Q
why is macrocirculation important?
A
- essential for maintaining blood pressure, distributing hormones, and delivering immune cells to different parts of the body
- critical role in thermoregulation, helping the body maintain a stable internal temp by redistributing blood to the skin or deeper tissues as needed
12
Q
Macrocirculation Disease and Disorders
A
- Atherosclerosis: building up of fatty deposits within the arterial walls, leading to narrowing and hardening of the arteries, which can result in heart attacks, strokes, and peripheral artery disease
- Hypertension: chronic high blood pressure can damage the arteries, leading to an increased risk of heart disease and stroke
Aneurysms:a weakening of the arterial wall that can lead to bulge or rupture potentially causing life-threatening internal bleeding
13
Q
Microcirculation definition
A
- refers to circulation of blood through smallest blood vessels in body
- capillaries, arterioles and venules
14
Q
importance of microcirculation?
A
- crucial for proper functioning of tissues and organs
- ensures that every cell in the body receives an adequate supply of oxygen and nutrients that waste products are efficiently removed
- vital for wound healing, immune response, and overall maintenance of tissue health
15
Q
Regulation of microcirculation
A
- neural regulation: autonomic NS can influence the constriction or dilation of arterioles, thereby controlling blood flow to different tissues
- hormonal regulation: hormones such as adrenaline and noradrenaline can cause vasoconstriction or vasodilation, affecting blood flow and pressure within the microcirculation
- local regulation: local factors (concentration of oxygen, CO2, and nitric oxide) can directly influence the dilation and constriction of blood vessels in the micro constriction, fine-tuned regulation of blood flow based on immediate needs of the tissue
16
Q
Diseases and Disorders of Microcirculation
A
- diabetic microangiopathy: diabetes can lead to the thickening of capillary walls, reducing the efficiency of nutrient and gas exchange which leads to complications such as diabetic retinopathy and neuropathy
- raynauds phenomenon: this condition involves abnormal constriction of arterioles in response to cold or stress, which leads to reduced blood flow to extremities and results in pain and discoloration of fingers or toes
- microvascular disease: associated with hypertension and diabetes, microvascular disease can impair blood flow to critical tissues, contributing to heart disease and other complications
17
Q
Location of the Heart
A
- heart is hollow muscular organ about the size of a fist, located between the lungs
- apex (tip) is pointed towards left hip
- contracts about 72 times per minute
18
Q
What are the layers of the heart?
A
- pericardium: surface of heart covered with protective layer of tissue
- 2 layers
1. fibrous pericardium: provides protection and anchors the heart in place
2. serous pericardium: produces lubricating fluid, which collects in the pericardial cavity to reduce friction of heart against other tissues (parietal and visceral pericardium)
19
Q
what are 3 layers of the heart?
A
- epicardium: visceral pericardium
- myocardium: thick twisting bundles of cardiac muscle to provide contractions
- endocardium: thin layer lining heart chambers
20
Q
what are the 2 cardiovascular circuits?
A
- human cardiovascular system has 2 loops that circulate blood back to heart
1. pulmonary circuit: carries blood from heart to lungs and back, picks up O2 and releases CO2
2. systematic circuit: carries blood from heart to body tissues and back, drops off O2 and picks up CO2
21
Q
what makes up pulmonary circuit?
A
- major blood vessels attached to heart are: pulmonary trunk (branches into right and left pulmonary arteries), pulmonary veins
22
Q
what makes up systematic circuit?
A
- major blood vessels attached to heart are: venae cavae (superior and inferior), aorta
23
Q
what are the 3 types of blood vessels?
A
- arteries
- veins
- capillaries
24
Q
what do arteries do?
A
carry blood away from heart, pass them to smaller arterioles then to capillaries
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what happens in capillaries?
- blood exchanges gases with surrounding tissues
- after dropping off O2 and picking up CO2, the capillaries collect blood into larger venules
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what do venules collect into?
- larger veins which return blood back to heart
27
what is the structure of capillaries
- one cell layer allowing for easy exchange of gases
28
what is the structure of arteries and veins?
- have 3 layers
1. tunica intima: slippery thin layer (endothelium, subendothelial layer, internal elastic lamina)
2. tunica media: thicker layer of muscle
3. tunica externa (tunica adventitia): fibrous connective tissue to support and protect
29
how does the structure of arteries, veins and capillaries differ?
arteries: thick walls (especially in tunica media layer), receive blood from heart under high pressure, so they need to be flexible
veins: thin walls, receive blood from tissues under low pressure
capillaries: 2 portions - shunt (short cut from artery to vein) and true capillaries (all tiny portions that exchange gases with the tissues
30
what are the 3 ways veins maintain blood flow even under low pressure?
- muscular pumping: as muscles contract, blood is squeezed through the veins
- respiratory pumping: expansion of chest during inhalation causes blood in veins to move
- valves: larger veins have valves to prevent backflow
31
what is the purpose of sphincters in capillaries?
- to restrict flow of blood to tissues when blood is needed elsewhere
- located between arterioles and shunt
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