Body Fluids And Circulation: Notes, Questions And Solutions

What Is a Circulatory System?

The circulatory system forms it all. It's a means by which the body fluid is moved containing important substances like oxygen, nutrients, and waste around the body. Knowledge about constituents and functions of body fluids and circulatory systems is of the essence in maintaining health and identifying disorders associated with them.

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Blood

• Blood is a specialized type of connective tissue. It is a strictly basic part of body fluid.

• Blood's chief functions include transportation, protection, and regulation.

Composition Of Blood

Blood is composed of Plasma and formed elements.

Plasma:

Plasma represents the fluid part of the blood; it forms about 55% of the entire volume of blood. The prime content of the plasma is water. Besides that, it also contains proteins, electrolytes, nutrients, hormones, and waste products.

Formed Elements:

The formed elements in blood are composed of erythrocytes, leucocytes, and platelets.

Erythrocytes:

This is meant to carry oxygen from the place of loading, the lungs, to the different parts of the body and then return with the carbon dioxide to the lungs, which will then be exhaled.

Leucocytes:

Popularly known as white blood cells, they form a part of the immune system, which combats various kinds of infections or diseases in the human body system.

Blood Platelets:

These are small portions of cells whose responsibility is taking crucial clotting of blood and healing of wounds.

Blood Groups

Blood grouping becomes very important and relevant not only for safe blood transfusions but also for understanding the aspects of immune responses.

ABO Blood Group System:

The ABO blood group system occurs in four different varieties or groups where the antigens of the red blood cells are distinguished: A, B, AB, and O blood groups.

Rh Grouping:

The Rh grouping is based upon either the presence or absence of an antigen known by the name Rh factor. According to the presence of this type of antigen, a person is Rh-positive or RH-negative.

Coagulation Of Blood

Coagulation is a process during which blood vessels dilate and blood clots are formed, attempting to prevent the excessive loss of blood if a vessel is injured.

It is a complex cascade of events that results in the conversion of fibrinogen to fibrin, forming the meshwork of the clot.

Lymph

Lymph is the clear fluid moving through a lymph vessel, which belongs to the immune system.

It cleanses the tissues of waste and toxins or other debris with the transportation of WBCs in and out of the lymph nodes.

Circulatory Pathways

The two types of circulatory systems are open and closed.

Open Circulatory System:

Blood is such that it does not always circulate within blood vessels. it flows freely off cavities, bathing organs directly.

Closed Circulatory System:

Blood remains inside vessels, leading to further efficiency of substance transportation. The human circulatory system along with all other vertebrates works this way.

Human Circulatory System

The circulatory system of humans consists of the heart, the system of blood vessels, and blood.

Heart Structure:

The heart is a muscular organ with a four-chambered structure, including two atria and two ventricles. It pumps the blood across the body parts.

Nodal Tissues:

Various nodes and tissues present in the heart are the sinoatrial and atrioventricular nodes. These nodes give rise to impulses, which regulate the heartbeat.

Blood Vessels:

Blood vessels are made up of arteries, veins, and capillaries. Blood leaves the heart through the arteries and returns to the heart through veins; in turn, the capillaries are the sites of delivery of material from the blood to the tissues and picking up material from the tissues.

Cardiac Cycle

• It is the process of one heartbeat, involving contraction and relaxation, that continuously circulates the blood throughout the body.

Electrocardiogram Ecg

• The ECG is a diagnostic method measuring the heart's electrical activity.

• It is useful in making various cardiac diagnoses and measures the rhythm of heartbeats in an individual.

Double Circulation

Double circulation is one of the features of the human circulatory system where the blood passes through the heart twice in one complete cycle. This consists of pulmonary and systemic circulations.

Pulmonary Circulation:

It is the flow of blood from the heart to the lungs and backwards to the heart. This is the process by which blood gets oxygenated and carbon dioxide removed.

Systemic Circulation:

The flow of oxygenated blood from the heart around the rest of the body and part deoxygenated blood back to the heart was another form of circulation.

Hepatic Portal System:

Veins forming a system that carries blood from the gastrointestinal tract and spleen to the liver were used to have waste detoxified and nutrients processed.

Regulation Of Cardiac Activity

• The autonomic nervous system along with the endocrine system controls cardiac activity.

• The sympathetic nervous system brings about an increase in heart rate, and the force of contraction, whereas the parasympathetic decreases heart rate.

Disorders Of The Circulatory System

There could be different disorders of the circulatory system, thus hindering the path towards well-being.

Hypertension, or High Blood Pressure:

High blood pressure means the pressure of the blood up against the walls of the arteries is very strong. Hypertension increases the risk of heart disease and stroke.

Coronary Artery Disease (CAD):

It refers to the reduction or blockage of coronary arteries that supply blood to the heart muscle. Reduced blood supply to the heart makes the organ more prone to a heart attack.

Angina:

Angina is a chest discomfort arising from poor blood circulation through the heart's muscles. It is mostly a symptom or sign of coronary heart disease.

Heart Failure:

A condition in which the heart's function becomes unable to sufficiently meet the needs of the organs and tissues in the body. It results in symptoms such as shortness of breath, tiredness, and fluid retention.

Coronary Thrombosis:

This is a blood clot inside one of the coronary arteries. Such thrombosis commonly leads to a heart attack.

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