The Heart and the Circulatory System Flashcards
Anatomical parts of the Heart
Atrium (left/right)
Ventricle (left/right)
Valves
Inferior/superior vena cava
Aorta
Pulmonary trunk
Pulmonary arteries
Pulmonary veins
Constituents of blood
RBCs (Red Blood Cells)
WBCs (White Blood Cells)
Plasma
Platelets
Functions of blood constituents
RBCs: Carry nutrients, oxygen, and carbon dioxide. Contains hemoglobin, which helps transport oxygen.
WBCs: Create antibodies, protect the body from infection, and eliminate cellular waste.
Platelets: Aid in blood coagulation (clotting).
Plasma: Fluid that transports antibodies and other blood cells.
Coagulation
Coagulation is the process of blood clotting or solidification.
It stops blood from escaping and helps protect against infection.
Antigens and Agglutinogens
An antigen is a substance that stimulates the production of antibodies.
Antigens are found on the surface of white blood cells (WBCs).
Agglutinogens are antigens found on red blood cells (RBCs).
Antibodies and Agglutinins
White blood cells (WBCs) produce antibodies.
Antibodies to agglutinogens are called agglutinins.
Agglutination
Agglutination refers to the reaction between agglutinins and agglutinogens, causing the solidification or clumping of blood.
Agglutination can be dangerous as it can lead to heart attacks and blood clots.
Blood Types and Agglutinogen systems
The two agglutinogen systems that determine blood types are the Rhesus System and the ABO System.
The blood type of a person with the Rhesus factor is positive (e.g., O+), while those without it have negative blood types.
Agglutinogen A corresponds to blood type A, agglutinogen B corresponds to blood type B, and both agglutinogens A and B correspond to blood type AB. Blood type O has neither agglutinogen A nor B.
Blood transfusion and compatibility
A blood transfusion is the transfer of blood products, usually red blood cells, from a donor to a recipient.
The rule of blood compatibility states that blood products should be transfused from a donor with a specific blood type to a recipient of the same blood type or a different blood type without causing agglutination.
Universal Donor and Universal Recipient
The universal donor is blood type O- (O negative).
The universal recipient is blood type AB+ (AB positive).
Characteristics of Blood Vessels
Arteries (Arterioles)
Direction: Away from the heart
Larger, thicker elastic walls (higher blood pressure)
Capillaries
Between arterioles and venules
Site of cellular action, where exchange of substances occurs
Veins (Venules)
Direction: To the heart
Less elastic, smaller in size, contain valves to prevent backflow
The two circulatory systems
Pulmonary System: Includes all blood vessels going to and from the lungs. Oxygenation of the blood occurs in this system.
Systemic System: Includes all other blood vessels that supply oxygen to various cells and organs in the body.
Blood pressure
Blood pressure is the force with which blood pushes against the walls of the arteries.
It is measured in millimeters of mercury (mmHg).
Blood Pressure reading
A blood pressure reading consists of two numbers, such as 120/80.
The first number represents the systolic pressure, which measures the pressure in the ventricles during contraction.
The second number represents the diastolic pressure, which measures the pressure between contractions.
Normal blood and hypertension
“Normal” blood pressure for a healthy adult is around 120/80 mmHg.
Hypertension refers to high blood pressure, which is above the normal range.
