Chapter 37 - Circulatory and Respiratory Systems Flashcards
The heart is enclosed by a protective sac of tissue called
pericardium
What is the myocardium?
the thick layer of muscle whose powerful contractions pump blood through the circulatory system
What is the chamber that receives the blood?
atrium
What is the chamber that pumps blood out of the heart?
ventricle
The right side of the heart pumps blood from the heart to
lungs (pulmonary circulation)
The left side of the heart pumps blood from the heart to
the rest of the body (systemic circulation)
What is the valve between the right atrium and the right ventricle?
tricuspid valve
What does the septum do?
prevents the mixing of oxygen-poor and oxygen-rich blood; divides left and right side of heart
What is the valve between the left atrium and left ventricle?
Mitral or bicuspid valve
What is the pacemaker?
the wave of muscle contractions through the heart
Arteries carry blood ___ from the heart
away
Veins carry blood ___ the heart
towards
What is hemoglobin?
the iron-containing protein that binds to oxygen in the lungs and transports it to tissues throughout the body where the oxygen is released
What is the purpose of the pharynx?
to serve as a passageway for both air and food
What is the trachea?
windpipe
Describe the pathway of oxygen through the respiratory system
environment-nasal cavities- pharynx- trachea- bronchi-bronchioles-alveoli
Describe the pathway of CO2 through the respiratory system
alveoli-bronchioles-bronchi-trachea-pharynx-nasal cavities-environment
What is the purpose of cilia?
to sweep trapped particles and mucus away from lungs toward pharynx
What is the purpose of mucus in the respiratory system?
moistens air and traps inhaled particles of dust or smoke
How does gas exchange in the lungs occur?
Oxygen dissolves in the moisture on the inner surface of the alveoli and diffuse across capillaries into blood. CO2 diffuses in the opposite direction.
What is the force that drives air into the lungs?
air pressure
How does the medulla oblongata know when it’s time to breathe?
By the amount of CO2 in the blood
What is chronic bronchitis?
swollen and clogged (by mucus) bronchi
What is emphysema?
loss of elasticity in the tissues of the lungs; can’t get enough oxygen to the body tissues or rid the body of excess carbon dioxide
