Chapter 3 – The Cardiorespiratory System Flashcards
Cardiorespiratory system
A system of the body composed of the cardiovascular and respiratory systems.
Cardiovascular system
A system of the body composed of the heart, blood, and blood vessels.
Heart
A hollow muscular organ that pumps a circulation of blood through the body by means of rhythmic
contraction.
Mediastinum
The space in the chest between the lungs that contains all the internal organs of the chest except
the lungs.
Sinoatrial (SA) node
A specialized area of cardiac tissue, located in the right atrium of the heart, which initiates the electrical impulses that determine the heart rate; often termed the pacemaker of the heart.
Atrioventricular (AV) node
A small mass of specialized cardiac muscle fibers, located in the wall of the right atrium of the heart, that receives heartbeat impulses from the sinoatrial node and directs them to the walls of the ventricles.
Atrium
The superior chambers of the heart that receive blood from the veins and force it into the ventricles.
Ventricle
The inferior chambers of the heart that receive blood from the corresponding atrium and force it into the arteries.
Stroke volume
The amount of blood pumped out of the heart with each contraction.
Heart rate (HR)
The rate at which the heart pumps; measured in beats per minute (bpm).
Cardiac output (Q)
Heart rate × stroke volume; the overall performance of the heart.
Blood
Fluid that circulates in the heart, arteries, capillaries, and veins; carries nutrients and oxygen to all parts of
the body and also rids the body of waste products.
Blood vessels
Network of hollow tubes that circulates blood throughout the body.
Blood functions
Transport, regulate, and protect.
Transportation
Blood transports oxygen and nutrients to cells, CO2 and waste away from cells, hormones to target tissues.
Regulation
Helps maintain stable body temperature, pH, water and electrolyte levels.
Protection
Clotting prevents fluid loss, while blood cells protect body against disease.
Arteries
Vessels that transport blood away from the heart.
Capillaries
The smallest blood vessels and the site of exchange of chemicals and water between the blood and body tissues.
Veins
Vessels that transport blood from the capillaries toward the heart.
Arterioles
Small terminal branches of an artery which end in capillaries.
Venules
The smaller veins that connect capillaries to the larger veins.
Respiratory system
A system of organs (the lungs and respiratory passageways) that collects oxygen from the external environment and transports it to the bloodstream.
Respiratory pump
Composed of skeletal structures (bones) and soft tissues (muscles) that work together to allow proper respiratory mechanics to occur and help pump blood back to the heart during inspiration.
Inspiration
The process of actively contracting the inspiratory muscles to move air into the body.
Expiration
The process of actively or passively relaxing the inspiratory muscles to move air out of the body.
Diffusion
The process of getting oxygen from the environment to the tissues of the body.
Maximal oxygen consumption (VO2max)
The highest rate of oxygen transport and utilization achieved at maximal physical exertion.
Right Atrium
Designed to receive the blood that is coming to the heart from the whole body. Thin walls; low pump of blood that flows to the lungs.
Left Atrium
Designed to receive the blood that is coming to the heart from the lungs. Thicker walls; high-pressure pump of blood that flows to the rest of the body.
Muscles of the respiratory pump consist of:
Inhalation - Diaphram, Scalenes, Pec Minor and Sternocleidomastoid.
Exhalation - Abdominals and Internal intercostals.
