Cardiovascular definitions Flashcards
(23 cards)
What is Haematopoiesis?
The process of blood cell formation, including the production of red blood cells, white blood cells, and platelets, primarily occurring in the bone marrow.
What is Erythropoietin (EPO)?
A glycoprotein hormone produced mainly by the kidney that stimulates the production of red blood cells in response to low oxygen levels.
What is Thrombopoietin?
A glycoprotein hormone produced in the kidney and liver that triggers the development of megakaryocytes into platelets.
What are Cytokines?
A broad category of glycoproteins produced by various immune and non-immune cells that act as signalling molecules, influencing cell proliferation, differentiation, and immune responses.
What are Leukocytes?
Also known as white blood cells, these are cells of the immune system involved in defending the body against infection and foreign substances.
What are the two classifications of Leukocytes?
They are broadly classified as granular (e.g., neutrophils, eosinophils, basophils) and agranular (e.g., lymphocytes, monocytes).
What is Haemoglobin (Hb)?
An iron-containing protein found in red blood cells that binds to oxygen and facilitates its transport throughout the body.
What is Phagocytosis?
The process by which certain cells, such as neutrophils and macrophages, engulf and digest pathogens, cellular debris, and other foreign material.
What are Lymphocytes?
A type of agranular leukocyte crucial for specific (adaptive) immunity, including T cells, B cells, and natural killer (NK) cells.
What are Monocytes?
A type of agranular leukocyte that is phagocytic and can differentiate into macrophages when they leave the bloodstream and enter tissues.
What are Platelets (Thrombocytes)?
Small, anucleated cell fragments derived from megakaryocytes in the bone marrow that play a critical role in blood clotting (haemostasis) and tissue repair.
What is the Pericardium?
The double-layered sac that encloses the heart, providing protection and reducing friction.
What is the Sinoatrial (SA) Node?
A specialized group of cardiac muscle cells in the wall of the right atrium that acts as the heart’s natural pacemaker.
What is the Atrioventricular (AV) Node?
A cluster of cardiac muscle cells located at the junction of the atria and ventricles that receives electrical impulses from the SA node.
What is the Cardiac Cycle?
The sequence of mechanical and electrical events that occur during one heartbeat, including atrial and ventricular systole and diastole.
What is an Electrocardiogram (ECG)?
A diagnostic tool that records the electrical activity of the heart over time, providing information about its rhythm and function.
What are Arteries?
Blood vessels that carry blood away from the heart; they typically have thick, elastic walls to withstand high pressure.
What are Arterioles?
Small arteries that branch off into capillaries and play a significant role in regulating blood pressure.
What are Capillaries?
The smallest blood vessels, forming a network between arterioles and venules, where the exchange of gases, nutrients, and waste products occurs.
What are Venules?
Small veins that collect blood from capillaries and merge to form larger veins.
What are Veins?
Blood vessels that carry blood back to the heart; they typically have thinner walls and lower pressure compared to arteries.
What is Capillary Exchange?
The process by which substances move between the blood in capillaries and the surrounding interstitial fluid and tissues.
What is Homeostasis?
The maintenance of a stable internal environment within the body despite external changes.
