Cardiovascular System Flashcards
(132 cards)
1
Q
What is heart disease?
A
- build up of fatty deposits which causes coronary arteries to become blocked
- insufficient oxygen delivered to the heart
- increases risk of heart attack
2
Q
Impact of sport on heart disease
A
- exercise makes heart bigger and stronger
- allows more blood to be pumped from the heart
- reduces risk of heart disease
3
Q
What is high blood pressure?
A
- extra strain on arteries and heart
- can lead to heart attack, heart failure and stroke
4
Q
Impact of sport on high blood pressure
A
- regular aerobic exercise can reduce blood pressure
- reduces risk of a heart attack
5
Q
What are cholesterol levels?
A
- low density lipoproteins
(bad cholesterol)
(increase risk of heart disease)
(transport in blood to tissues) - high density lipoproteins
(excess transport to liver)
6
Q
Impact of sport on cholesterol levels
A
- lowers bad LDL levels
- increases good HDL levels
7
Q
What is a stroke?
A
- occurs when blood supply to the brain is cut off
- causes damage to brain cells
8
Q
Impact of sport on stroke
A
- lowers blood pressure
9
Q
Define heart rate
A
The number of times the heart beats per minute
10
Q
Define stroke volume
A
The volume of blood pumped from the heart per beat
11
Q
Define cardiac output
A
The volume of blood pumped from the heart per minute
12
Q
What is the equation for cardiac output
A
Heart rate x stroke volume
13
Q
Define anticipatory rise
A
Increase in heart rate in anticipation of an activity
14
Q
Define venous return
A
The volume of blood returning to the heart via veins
15
Q
Define elasticity of cardiac fibres
A
Stretching on cardiac fibres during diastole
16
Q
Define ejection fraction
A
The percentage of blood pumped out of the left ventricle per beat
17
Q
Effect of elasticity of cardiac fibres on ejection fraction
A
More the fibres stretch, increased force of contraction, more percentage of blood pumped out of left ventricle per beat (ejection fraction)
18
Q
Define cardiac tissue contractility
A
Ability of heart muscle to contract and pump blood
19
Q
Effect of contractility on stroke volume
A
Increased contractility, increased force of contraction, increased ejection fraction, increased stroke volume
20
Q
What does Starling’s Law state?
A
The greater venous return, the greater the stroke volume
21
Q
Use Starling’s Law to explain how stroke volume increases during exercise
A
- during exercise, venous return increases
- this increases the diastolic filling of the heart which leads to the cardiac muscle being stretched
- this results in a more powerful contraction which leads to an increased ejection fraction
- this increases the stroke volume
22
Q
How will heart rate differ between a trained and untrained athlete at rest?
A
Lower resting heart rate in trained athlete
23
Q
How will stroke volume differ between a trained and untrained athlete at rest?
A
Higher resting stroke volume in trained athlete
24
Q
How will cardiac output differ between a trained and untrained athlete at rest?
A
Stays the same
25
Define systole
The phase of the heart beat when the heart contracts to pump blood
26
Define diastole
The phase of the heart beat when the heart relaxes to fill with blood
27
Define myogenic
Originating in the muscle as an impulse or sensation
28
Define the sino-atrial node
Small mass of cardiac muscle that generates the heart beat
29
Define the atrioventricular node
Relays the impulse between upper and lower sections of the heart
30
Define the bundle of His
Collection of muscle cells that transmit electrical impulses from the atrioventricular node via bundle branches to Purkinje fibres
31
Definitely bundle branches
Carries an electrical impulse from the bundle of His to Purkinje fibres
32
Define Purkinje fibres
Muscle fibres that conduct impulses in the walls of ventricles
33
What happens in the first stage of the cardiac conduction system?
Sino-atrial node sends an impulse across atria causing them to contract
34
What happens in the second stage of the cardiac conduction system?
Impulse arrives at the atrioventricular node where it is delayed, allowing ventricles to fully fill with blood
35
What happens in the third stage of the cardiac conduction system?
The impulse travels down the bundle of His located in the septum
36
What is the fourth stage in the cardiac conduction system?
Impulse travels along Purkinje fibres branched along the base of right and left ventricles causing them to contract
37
Sally Always Aims Balls Past Vicky
Sino-atrial node
Atrial systole
Atrioventricular node
Bundle of His
Purkinje fibres
Ventricular systole
38
4 factors affecting change in rate of the conduction system
- neural control mechanism
- chemoreceptors
- baroreceptors
- proprioceptors
39
What is the role of the sympathetic nervous system in heart rate regulation?
Stimulates the heart to beat faster
## Footnote
The sympathetic nervous system is part of the autonomic nervous system responsible for increasing heart rate.
40
What does the parasympathetic nervous system do in relation to heart rate?
Returns the heart to its resting level
## Footnote
The parasympathetic nervous system is part of the autonomic nervous system that decreases heart rate.
41
What are the two main parts of the nervous system?
* Central nervous system
* Peripheral nervous system
## Footnote
The central nervous system consists of the brain and spinal cord, while the peripheral nervous system includes all other neural elements.
42
Where is the cardiac control center located?
In the medulla oblongata of the brain
## Footnote
The medulla oblongata regulates vital processes such as breathing and heart rate.
43
What happens to sympathetic impulses when heart rate increases?
Sympathetic impulses are sent to the SAN and there is a decrease in parasympathetic nerve impulses
## Footnote
This interaction leads to an increase in heart rate.
44
What types of receptors stimulate the cardiac control center?
* Chemoreceptors
* Baroreceptors
* Proprioceptors
## Footnote
These receptors provide the cardiac control center with necessary feedback regarding the body's physiological state.
45
True or False: The sympathetic nervous system decreases heart rate.
False
## Footnote
The sympathetic nervous system is responsible for increasing heart rate.
46
Fill in the blank: The _______ regulates processes that keep us alive such as breathing and heart rate.
medulla oblongata
## Footnote
The medulla oblongata is crucial for autonomic functions.
47
What are chemoreceptors?
Tiny structures in the carotid arteries and aortic arch that detect changes in blood acidity caused by carbon dioxide concentration
## Footnote
Chemoreceptors play a crucial role in monitoring the chemical composition of blood.
48
Where are chemoreceptors located?
In the carotid arteries and aortic arch
## Footnote
These locations are critical for monitoring blood gases and regulating cardiovascular functions.
49
What do chemoreceptors detect during exercise?
An increase in carbon dioxide
## Footnote
This detection is vital for adjusting respiratory and cardiovascular responses during physical activity.
50
How does carbon dioxide affect heart rate?
It controls heart rate by stimulating the sympathetic nervous system
## Footnote
Increased carbon dioxide levels signal the body to increase heart rate to meet metabolic demands.
51
True or False: Increased concentration of carbon dioxide in the blood stimulates the parasympathetic nervous system.
False
## Footnote
Increased carbon dioxide actually stimulates the sympathetic nervous system, resulting in a faster heart rate.
52
Fill in the blank: Increased concentration of carbon dioxide in the blood will have the effect of stimulating the _______.
sympathetic nervous system
## Footnote
This response is crucial for adjusting heart rate and blood flow during various activities.
53
What are baroreceptors?
Special sensors in tissues in the aortic arch, carotid sinus, heart, and pulmonary vessels that respond to changes in blood pressure.
54
What do baroreceptors establish?
A set point for blood pressure.
55
What happens when blood pressure increases above or decreases below the set point established by baroreceptors?
Baroreceptors send signals to the medulla in the brain.
56
How does the set point of baroreceptors change at the start of exercise?
The set point increases.
57
Why is it important for the baroreceptor set point to increase at the start of exercise?
To prevent heart rate from slowing down, which would negatively affect performance.
58
What is the role of proprioceptors?
Sensory nerve endings located in muscles, tendons, and joints that detect changes in muscle movement.
59
What do proprioceptors do when they detect changes in muscle movement?
Send an impulse to the medulla, which then sends an impulse through the sympathetic nervous system to increase heart rate.
60
What effect does the parasympathetic system have on heart rate?
It stimulates the SAN, resulting in a decrease in heart rate.
61
What is the relationship between chemoreceptors and heart rate?
An increase in O2 levels leads to an increase in heart rate.
62
Fill in the blank: Baroreceptors respond to an increase in BP by _______.
decreasing heart rate.
63
Fill in the blank: Proprioceptors detect an increase in muscle _______ and lead to an increase in heart rate.
movement.
64
What is the release of adrenaline during exercise called?
Hormonal control
## Footnote
Hormonal control refers to the process by which hormones regulate bodily functions, particularly during physical activity.
65
What type of hormone is adrenaline?
Stress hormone
## Footnote
Adrenaline, also known as epinephrine, is released in response to stress and prepares the body for 'fight or flight' situations.
66
Which nerves release adrenaline during exercise?
Sympathetic nerves and cardiac nerve
## Footnote
These nerves are part of the autonomic nervous system and are activated during physical stress or exercise.
67
What does adrenaline stimulate in the heart?
Sinoatrial node (SAN)
## Footnote
The SAN is the natural pacemaker of the heart, regulating heart rate.
68
What are the effects of adrenaline on heart function?
Increases heart rate and force of contraction
## Footnote
This leads to enhanced cardiac output, which is crucial during exercise.
69
What is the result of increased cardiac output during exercise?
More blood is pumped to working muscles
## Footnote
Increased blood flow allows muscles to receive more oxygen for energy production.
70
Fill in the blank: Adrenaline is released by _______ during exercise.
sympathetic nerves and cardiac nerve
71
True or False: Adrenaline decreases the speed and force of heart contractions during exercise.
False
## Footnote
Adrenaline actually increases both speed and force of contractions.
72
What is vascular shunting?
The body's response to exercise by altering the distribution of blood flow around the body.
## Footnote
Vascular shunting prioritizes blood flow to essential muscles during physical activity.
73
Define vasodilation.
Widening of arteries to increase the supply of blood and oxygen to the working muscles and remove lactic acid.
## Footnote
Vasodilation occurs during exercise to meet the increased metabolic demands of active tissues.
74
What is vasoconstriction?
Narrowing of arteries to decrease the blood supply to non-essential organs.
## Footnote
Vasoconstriction helps redirect blood flow to vital areas during physical exertion.
75
What are precapillary sphincters?
Tiny rings of muscle located at the opening of the capillaries.
76
What is the function of precapillary sphincters?
Aids blood redistribution by constricting or dilating.
77
What happens when precapillary sphincters constrict?
The blood flow is restricted through the capillary.
78
What happens when precapillary sphincters dilate?
Blood flow is increased.
79
During exercise, what happens to the capillary networks supplying skeletal muscle?
They will be dilated to increase blood flow and saturate the tissues with oxygen.
80
What chemical changes occur during exercise?
Increased carbon dioxide and lactic acid
## Footnote
These changes are detected by chemoreceptors.
81
What system is stimulated by detected chemical changes during exercise?
The automatic nervous system (parasympathetic and sympathetic)
## Footnote
This stimulation leads to vasoconstriction and vasodilation of blood vessels.
82
What happens to blood vessels due to increased sympathetic stimulation during exercise?
Vasoconstriction to the organs and vasodilation to the muscles occurs
## Footnote
This results in more blood being redistributed to the muscles.
83
Why is the redistribution of blood important during exercise?
It increases supply of oxygen to working muscles and removes waste products
## Footnote
It also ensures more blood goes to the skin and directs more blood to the heart.
84
Fill in the blank: The automatic nervous system is composed of _______ and sympathetic systems.
[parasympathetic]
## Footnote
The parasympathetic system works alongside the sympathetic system.
85
True or False: Vasodilation occurs in organs during sympathetic stimulation.
False
## Footnote
Vasodilation occurs in muscles, while vasoconstriction occurs in organs.
86
What is venous return?
The process of deoxygenated blood returning to the heart from the body
## Footnote
Venous return is essential for maintaining circulation and ensuring that oxygen-poor blood is sent to the lungs for reoxygenation.
87
What are the two types of circulation?
* Pulmonary: deoxygenated blood from the heart to the lungs and oxygenated blood back to the heart
* Systemic: oxygenated blood from the heart to the body and deoxygenated blood back to the heart
## Footnote
These two circulatory paths are crucial for gas exchange and delivering oxygen to tissues.
88
List the sequence of blood vessels from the heart to the body and back.
* Heart
* Arteries
* Arterioles
* Capillaries
* Venules
* Veins
* Heart
## Footnote
This sequence illustrates the pathway blood takes through the circulatory system.
89
What is blood pressure?
The force exerted by the blood against the walls of blood vessels
## Footnote
Blood pressure is a critical measure of cardiovascular health and is influenced by cardiac output and vascular resistance.
90
What is the formula for blood flow?
Blood flow = blood pressure x resistance
## Footnote
This formula indicates how blood pressure and resistance work together to determine the rate of blood flow in the circulatory system.
91
What is systolic pressure?
The pressure in the arteries when the ventricles contract
## Footnote
Systolic pressure is a key component of blood pressure readings, representing the peak pressure during heartbeats.
92
What is diastolic pressure?
The pressure in the arteries when the ventricles relax
## Footnote
Diastolic pressure reflects the minimum pressure in the arteries when the heart is at rest between beats.
93
True or False: The pressure in the veins is high, requiring no mechanisms for venous return.
False
## Footnote
The pressure in the veins is low, necessitating active mechanisms to assist in venous return.
94
Fill in the blank: The sequence of blood vessels is heart → arteries → arterioles → capillaries → _______ → veins → heart.
venules
## Footnote
Venules are small blood vessels that collect blood from capillaries before it returns to the veins.
95
What is the skeletal muscle pump?
A mechanism that aids venous return by muscles contracting and relaxing, pressing on nearby veins to squeeze blood towards the heart.
## Footnote
The contraction of skeletal muscles generates a pumping effect that assists in moving blood against gravity.
96
How does the respiratory pump contribute to venous return?
It involves pressure changes in the thoracic and abdominal cavities during breathing that compress nearby veins, assisting blood return to the heart.
## Footnote
The act of breathing creates a pressure gradient that facilitates venous return.
97
What is the function of pocket valves in veins?
They ensure that blood does not flow backward in veins, which are under low pressure.
## Footnote
Pocket valves are crucial for preventing backflow and maintaining unidirectional blood flow.
98
What role does smooth muscle play in venous return?
Smooth muscle can constrict to increase venous return.
## Footnote
The contraction of smooth muscle in the walls of veins helps to propel blood back towards the heart.
99
How does gravity affect venous return from the upper body?
Gravity aids the venous return of blood from areas of the upper body above the heart.
## Footnote
Blood from regions above the heart must work against gravity, making venous return more challenging.
100
What happens to cardiac output after exercise?
Cardiac output is still high but there may be insufficient pressure to maintain venous return.
## Footnote
Insufficient pressure can lead to lightheadedness or dizziness due to blood pooling in pocket valves.
101
What can prevent blood pooling after exercise?
Performing an active cool-down will keep skeletal muscles pump and respiratory pump working.
## Footnote
This helps maintain venous return during the recovery phase.
102
Why is maintaining venous return during exercise important?
It ensures skeletal muscles receive enough oxygen to meet the demands of activity.
## Footnote
During exercise, skeletal muscles are constantly contracting, and elevated breathing aids in venous return.
103
What determines venous return?
Venous return is determined by a pressure gradient.
## Footnote
The pressure gradient is the mean systemic pressure minus the right atrial pressure.
104
What factors affect venous return?
An increase in venous pressure or a decrease in right atrial pressure and venous resistance leads to an increase in venous return.
## Footnote
These changes enhance the pressure gradient driving venous return.
105
What is the typical blood pressure in the right atrium and peripheral veins?
The blood pressure in the right atrium and peripheral veins is normally low.
## Footnote
This low pressure is crucial for the pressure gradient that drives venous return.
106
What is haemoglobin?
Iron-containing pigment found in the red blood cells
## Footnote
Haemoglobin plays a critical role in transporting oxygen from the lungs to the rest of the body.
107
What is the function of myoglobin?
Transports oxygen to the muscle and stores oxygen in the muscle fibres for use by mitochondria during aerobic respiration
## Footnote
Myoglobin is particularly important in muscle tissues that require a steady supply of oxygen.
108
Where does respiration and energy production occur?
Mitochondria
## Footnote
Mitochondria are often referred to as the powerhouse of the cell.
109
What is oxyhaemoglobin?
Occurs when oxygen combines with haemoglobin in areas of high oxygen partial pressure
## Footnote
This process is essential for efficient oxygen transport in the bloodstream.
110
What is oxynaemoglobin dissociation?
The process of oxygen being released from oxyhaemoglobin in areas of low oxygen partial pressure
## Footnote
This allows for oxygen to be delivered to tissues that need it.
111
Define partial pressure.
Gas will move from areas of high partial pressure to areas of low partial pressure
## Footnote
The partial pressure of O2 is high in alveolar capillaries but low in capillaries at skeletal muscle during exercise.
112
True or False: The partial pressure of oxygen is higher in capillaries at skeletal muscle during exercise.
False
## Footnote
The partial pressure of oxygen is lower in skeletal muscle capillaries during exercise.
113
What does affinity refer to in the context of oxygen transport?
The degree to which a substance tends to combine with another
## Footnote
Affinity is crucial for understanding how haemoglobin binds and releases oxygen.
114
What is formed when oxygen combines with haemoglobin in the lungs?
Oxyhaemoglobin
## Footnote
This occurs at high partial pressure (pp) of O2.
115
Where does oxyhaemoglobin travel from the lungs?
To the capillaries surrounding the skeletal muscles
## Footnote
Oxyhaemoglobin is transported in the bloodstream.
116
What happens to oxygen at the muscle tissue?
Oxygen is released from oxyhaemoglobin
## Footnote
This process is known as oxyhaemoglobin dissociation.
117
What protein stores oxygen in the muscle?
Myoglobin
## Footnote
Myoglobin has a higher affinity for oxygen than haemoglobin.
118
What is the role of myoglobin in muscle tissue?
To store oxygen for the mitochondria until it is used by the muscles
## Footnote
Myoglobin releases oxygen when needed during muscular activity.
119
What occurs when the partial pressure of oxygen is high?
Oxygen combines with haemoglobin to form oxyhaemoglobin
## Footnote
This happens primarily in the lungs.
120
What happens to oxygen when the partial pressure is low, such as in muscle tissue?
Oxygen leaves oxyhaemoglobin
## Footnote
This process is called oxyhaemoglobin dissociation.
121
What is the primary use of oxygen by mitochondria?
To produce energy
## Footnote
This energy is utilized by the muscles for contraction.
122
What type of respiration occurs in the absence of oxygen?
Anaerobic respiration
## Footnote
This occurs when oxygen is not present for aerobic respiration.
123
How does low partial pressure of oxygen and myoglobin affect muscle performance?
It allows muscles to receive more oxygen for contraction during exercise
## Footnote
This is crucial for sustained muscular activity.
124
What are the 3 factors responsible for the Bohr shift?
- increase in blood pressure
- pp of CO2 increases
- pH decreases
125
What is the arterio-venous difference?
The difference between the oxygen content of the blood arriving at the muscles and venous blood leaving the muscles
126
What is the significance of A - vOz difference?
It indicates how much oxygen is needed for energy production and leads to improved performance.
127
What happens to the A - vOz difference as performance improves?
The A - vOz difference increases.
128
What is the variation in A - vOz difference between trained and untrained individuals?
Trained performers can extract a greater amount of oxygen from the blood.
129
Why can trained performers extract more oxygen from the blood?
Because tissues become more efficient at taking up oxygen.
130
Fill in the blank: The A - vOz difference is needed for _______.
[energy production]
131
True or False: The A - vOz difference decreases in trained individuals compared to untrained individuals.
False
132
What is steady state exercise?
Where oxygen demand meets oxygen supply
