The Cardiovascular System Assignment Sample

Introduction To The Cardiovascular System Assignment

Task 1 –

Heart Structure and Function

Demonstrate the heart's tissue layers and their functions

Figure 1: The external view of the heart before dissection

(Source: Youtube.com, 2024)

Figure 2: The internal view of the heart after dissection

(Source: Youtube.com, 2024)

In general, the left ventricle is about to be twice as thick as the right, and this area is important because a more powerful force is being exerted for all the blood supply in the body (Verzicco, 2022). On the other hand, the right ventricle carries the blood to the lungs (pulmonary circulation) and is relatively much thinner than the left (Verzicco, 2022).

There is a relationship between smooth surfaces and the endocardium that is characteristic of the endocardium, which contributes to smooth flow of blood and to blood clot formation. Aside from them we can observe the ventricles and possibly the valves that prevent blood to once where it has the pump worked efficiently.

The human heart differs from other muscles of the body because it's not placed in the middle chest, but shifted to the left side (Bär et al., 2022). There's also a soft, muscular organ in the heart that's about the size of a man's fist. It is a circulatory pump, the main component of man's body in that it transfers oxygen and nutrients to all parts of his body as well as removing carbon dioxide and other waste materials.

There are layers of tissue which include endocardium, myocardium and epicardium in the heart's structure (Buijtendijk, Barnett and Hoff, 2020).

The heart is composed of three tissue layers:The heart is composed of three tissue layers:

Endocardium: The atrial lining which is the innermost layer, closing the atrium and thus the valves itself (Peate, 2021). It's made up of two layers of endothelium cells, which form a consistent layer covering the heart chambers and valves in order to ensure that next generation blood flow is maintained without turbulence.

Myocardium: The middle of the heart has the thickest part, consisting of heart muscle tissue (Kristen et al., 2019). This layer is dependent on the heart's action to supply blood through a pump. The thickness of myocardium is adjusted from one part of the heart to another, and reaches its peak point in the left ventricle where blood can be withdrawn into systemic circulation for all body organs (Kristen et al., 2019).

Epicardium: This layer is formed by the thinnest tissue of connective tissues that makes up the wall of the pericardium which covers the heart. It serves as a protective sheath and lies forward of skeletal system containing blood vessels, nerves, and lymphatics.

Performance with respect to structure

Endocardium: Its low friction design helps the blood moves around the heart smoothly which means the heart is able to pump blood more effectively.

Myocardium: It is a cardiac muscle that can make a rhythmical contraction and relaxation that is important as to the activity of the heart's pumping (Banerjee, Pradip Kumar Das and Mukherjee, 2023). The change in myocardium thickness indicates that different parts of the circulatory system do not only require different blood pressure values, but also that they are capable of using different mechanisms to deliver blood to the required areas through the different thickness of the surrounding myocardium.

Epicardium: The vessel has ability to protect the heart and provides. the heart muscle with the nutrients through its vessels for their blood circulation (Kim, 2022).

Differentiate between coronary, pulmonary, and systemic circulation

Figure 3: Difference between coronary, pulmonary, and systemic circulation

(Source: Youtube., 2024)

The metabolism of the whole body is set in motion by a complex system of circulatory pathways which in turn is comprised of the coronary, pulmonary and systemic circuits and each of these is vital to life support (Furst and José González?Alonso, 2023). Coronary circulation itself forms a whole intricate network of arteries and veins for the eventual distribution of blood to and fro the myocardium. A key role of the coronary arteries is to deliver oxygenated blood to enable the heart's muscle to have energy to perform its ultimate duty of pumping blood unceasingly to every part of the body (Furst and José González?Alonso, 2023b). The system starts where the coronary arteries, encircling the cardiovascular, take off from the aorta, and ends by draining the venous blood into the right atrium. However, the pulmonary flow is a powerful and complex loop between the lungs and the heart which is mainly responsible for this exchange process.

The right ventricle's deoxygenated blood flows to the pulmonary arteries where they give off CO2) and to the lungs (where it gets O2; it is re-oxygenated (Verzicco, 2022). On the other hand, pulmonary veins transport this fresh oxygenated blood from the lungs to the left atrium of the heart. In contrary to the foregoing, the systemic circulation system embraces the other parts which are the majority of vascular system with gas transporting of oxygen-rich blood to all body tissues being its task (Burggren, Filogonio and Wang, 2019).

In order to provide the tissues with the necessary nutrients and oxygen, the main pump of the body, the left ventricle, pumps oxygenated blood into the aorta, from where it divides into a system of arteries with large and small sizes, and returns the oxygenated blood to the right atrium through the veins. These differences not only reveal the level of oxygen in these vessels, their anatomy, and the specific upper contribution of these vessels, but also the complexity and efficiency of the cardiovascular system. The specific physiological requirements to be addressed by each circuit are: from the thick muscular walls of heart vessels that require high energy due to a systemic requirement for different tissues and pulmonary demand for gas exchange.

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Task 2 –

The Conduction Pathway and the Cardiac Cycle

Describe the parts of the cardiac conduction pathway and their functions

An outstanding biological engineering structure responsible for coordinating the rythm of the heart is the cardiac conductor system of the human heart (Hendrickson et al., 2021). In command of the process is the SA node, which is situated in the right atrium, either inside or around its wall and acts as the heart's pacemaker by sending electric impulses with the sense of direction of the heart's rhythm to the whole heart. Therefore, the electrical wave begins in the SA node and travels to the AV node which is located at a convergence between the atrium and ventricles.

Figure 4: Cardiac Conduction System

(Source: Mohan, Boukens and Christoffels, 2017)

The AV node remains the pivotal one, it excludes signal until the upstroke of the atrial muscle is completed and blood accumulates in the ventricles (McCauley et al., 2020). The impulse travels down the bundle of His, forks at its septal extremities to the right and left bundle branches, and ends in the Purkinje fibres. These fiber conduits diminish electric signal from IM ????????????????? ?? ???????????, inducing their powerful contraction. An organized pattern of events makes breathlessness in the perfect coordination. Therefore, in order to maintain life, blood circulation is carried out in the lungs for oxygenation, which is carried out throughout the body.

Assessing to how the conduction pathway coordinates different stages of the cardiac cycle

The intrinsic feature of the cardiac conduction pathway is to precisely calibrate heartbeat so that the consecutive atrial and ventricular contractions are perfectly synchronized in a timely manner to assure an adequate blood flow through the whole cardiac cycle (Ripplinger et al., 2022). The SA node begins this cycle by sending out a pulse that starts the atriums collectively contracting (atrial systole) while the P wave is displayed simultaneously on a basic ECG. This electrical activity is the death of the filling in the ventricles. After a small delay, the next step takes place.

Figure 5: Optical Electrophysiology in the Developing Heart

(Source: Thomas et al., 2018)

The motion of the impulse is arrested at the AV node and then it is given a chance to dip into the ventricels and fill it with the last blood from the heart (Sikdar, 2023). As seen on the ECG as a QRS complex, the premature impulse passes through the AV bundle to the branches of the AV bundle and to the Purkinje fibers that cause ventricular contraction, as seen on the ECG as a QRS complex. The blood flow to the two jumpers, the systemic and pulmonary state, is covered in this section. In the end, after the touching point of diastole, the muscles stop and show the T shape on ECG, and into this cycle next zone seconds, there's the refilling of heart chambers for next cycle.

Discussed the relation between the cardiac cycle and stages in an electrocardiogram (ECG)

The ECG is a graphical form of the electrical activity involved in the the cardiac cycle which regulates the heart motions (Saini and Gupta, 2021). Interaction of ECG with cardiac cycle is a result of the organ's electric conduction system working with utmost precision.

Figure 6: The U wave is not visible in all ECGs.

(Source: Med.libretexts.org, 2024)

The QRS complex, which refers to the simultaneous P waves and QRS complexes in the ventricles during the strong ventricular systole, is defined as the interval between the P wave and the subsequent contraction of the atria. The time at the end of the five-second loop begins, when the ventricles are contracting, moving blood to the lungs and everywhere else.

Figure 7: Illustration of a patient undergoing a 12-lead ECG

(Source: Med.libretexts.org., 2024))

ST segment and T wave marked the working phase of ventricular repolarization when the ventricles are getting ready for the next cycle (Med.libretexts.org., 2024). When the ventricles are fully repolarized and resting again, a new literary trigger will be ready in the SA node at the end of T wave. The exact alignment of these electrical events enables the heart's chambers to interact in order to ensure that there is a constant steady flow of blood.

When an ECG lacks a clear pattern of P waves, QRS complexes, or T waves, this usually means ventricular fibrillation which is a very serious form 0f arrhythmia that can result in a person's death. The rhythm of your heart becomes very fast and irregular, such that it can hardly perform its duty of pumping blood now, and thus it starts to go along the way of twitching and fibrillating, forming an arrhythmia. The consequence of delayed intervention in the case of ventricular fibrillation by electrical defibrillation (use of the AED) can be a sudden death with the patient dying within a few minutes of the onset (Lee et al., 2021). AV block is usually associated with the course of myocardial infarction and heart failure and is associated with blocking of the fast action loop from the heart muscle to the entrance node. Consequently, the cardiac muscle contractions are suddenly accelerated and slowed down. The result of insufficient blood circulation throughout the body can sometimes lead to this condition.

Task 3 –

The Structure and Function of Arteries, Veins and Capillaries

Compare and contrast the structure and function of arteries, veins, and capillaries

Arteries

Structure: The outside layer of arteries is the thinnest, known as the tunica externa, the middle layer is the muscular layer, which is the most prominent, known as the tunica media, and the inside layer or endothelial layer, which is the thinnest, known as the tunica intima (Peate, 2021). This thickness is due to the great amounts of smooth muscle and elastic fibers, which are all part of the mechanics of blood pressure regulation.

Function: Artries serve the function of blood vessels which transport the oxygen enriched blood to different tissues of the body with the aid of the heart (Kim, 2022b). Such a solidity may allow membranes to survive and foster the high pressure generated by the beating of the heart. They also exert a sort of muscular contraction and relaxation, and these abilities work tremendously to regulate blood pressure and to direct the flow of blood.

Veins

Structure: In thinner fabrics and larger lumen than their function, veins arise from the arteries. They're not only the valves, they're also designed to prevent blood flow backwards and thus ensure a constant flow of oxygen into the heart. Vessels have less smooth muscle than arteries, and these muscle fibres form some elastic tissue (Ripplinger et al., 2022).

Function: Tributary viruses carry oxygen deficient blood from the tissue back to the body. Valves, which are designed to prevent backflow of blood and muscle contractions that have a stronger effect when walking in order to pump blood from the lower extremities, counteract this difference in pressure between veins.

Capillaries

Structure: The endothelium, a single layer of cells that line the inner walls of the blood vessels, forms the capillaries, the smallest blood vessels (Fleischer, Tavakol and Vunjak?Novakovic, 2020). They have a very small diameter, equal to the size of a single blood cell. They follow one-by-one sequence of blood cells passing through the lumen.

Function: Capillaries are the duty centres where nutrients and wastes are exchanged from the blood to the tissues. Thin walls do not only support a gas exchange (oxygen and carbon dioxide), nutrients, and metabolic waste products transportation, but the bloodstream and cells interaction.

Task 4 –

Regulation of Blood Pressure

Explain how the body monitors and maintains blood pressure

Human organism has and maintains a complex, comprehensive system of multiple mechanisms to control blood pressure at all times and under any circumstances (Parati et al., 2020). At its base are the baroreceptors, the neurons that quip in the carotid artery and aorta walls, which form the core of this regulatory network. These baroreceptor-receptive areas, responsive to fluctuations in arterial pressures, will send immediate signals to the brainstem (specifically to the medulla oblongata region of the cardiovascular center) if an anomaly is detected. The autonomic nervous system will adjust the heart rate, stroke volume and extent of vasoconstriction with support from the cardiovascular centre. The sympathetic nervous system doing this as the stimulated by the rise in blood pressure, while the retroactive transmission of actions creating the onset of the parasympathetic nervous system is done to decreases the heart rate and the sympathetic nervous system relaxation of the blood vessels so that the blood pressure can be reduced (Parati et al., 2020).

On the other hand, contraction of the blood pressure, the sympathetic nervous system is led to increase and which leads to an increase of the heart rate and by constricting the blood vessels up, to enhance the pressure as well. Moreover, the body resort to the system known as renin-angiotensin-aldosterone-system (RAAS), which is activated to increase circulatory volume when blood pressure gets reduced. Renin, an enzyme which starts a cascade, produces angiotensin II, a renin release is considered to be an important vasoconstrictor, and leads to aldosterone secretion and stimulates reabsorption of sodium and water. Thus, blood volume and pressure are increased. Additionally, kidney contributes to long term blood pressure regulation, maintaining balance in the fluid by adjusting urine amount accordingly, in reactions to blood pressure variations (Goldstein, 2022). While working independently, these systems are interconnected to produce blood pressure which is necessary for operating and giving a normal function to the organs and tissues.

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