Cardiovascular, Respiratory & Excretory System Functions

Circulatory System and Blood Components

Blood Cells and Platelets

Red blood cells (RBC): They bind oxygen via hemoglobin and transport it through the bloodstream.

White blood cells (WBC): Defend the body from infectious agents.

Platelets: Involved in blood clotting.

Heart Muscle and Valves

Myocardium: Makes the heart contract and relax.

Mitral and tricuspid valves: Let blood flow from the atria to the corresponding ventricles and prevent backward movement.

Semilunar valves: Prevent backflow of blood into the ventricles.

Capillaries and Circulation Types

Capillaries: Perform exchange of substances between blood and cells.

Pulmonary (minor) circulation: Its function is to facilitate the exchange of respiratory gases.

Systemic (greater) circulation: Transports oxygen and nutrients to all tissues and removes wastes produced by the cells.

Vascular Conditions and Disorders

• Hypertension: Increased pressure of the blood on the arterial walls.
• Varices (varicose veins): Swollen veins that can be caused by increased venous pressure, sometimes related to increased abdominal pressure.
• Stroke: Occurs when blood flow to part of the brain is interrupted.
• Pulmonary embolism: Blockage of a branch of the pulmonary artery.
• Aneurysm: A localized dilation of an arterial wall.
• Myocardial infarction: Originates from partial or total obstruction of the coronary arteries.
• Coagulation disorders: Disorders affecting normal blood clotting.

Respiratory System

Ventilation and Breathing

Pulmonary ventilation: The process of renewing the air contained in the lungs.

Inspiration: Occurs through the contraction of respiratory muscles.

Expiration: Occurs when the respiratory muscles relax.

Lung Diseases

Emphysema: Progressive destruction of the alveoli (air sacs).

Pneumonia: An acute infection of the lung tissue.

Excretory System and Waste Removal

Excretion and Major Organs

Excretion: The process by which the body removes waste products from chemical reactions (metabolism).

Kidneys: The most important excretory organs; they eliminate wastes produced by cells and help purify the blood.

Lungs: Expel carbon dioxide produced in cellular respiration.

Sweat glands (sudoriferous glands): Regulate body temperature through sweating.

Liver: Eliminates some wastes and other substances by secreting them into bile; bile pigments are among these substances.

Renal Structure and Function

Nephron: The functional unit of the kidney. The Bowman's capsule surrounds a tuft of capillaries called the glomerulus.

Renal artery: A branch of the aorta that carries blood containing wastes to the kidney.

Renal vein: Carries filtered (purified) blood away from the kidney.

Hemodialysis: Involves removing metabolic wastes from the blood.