Chapter 19: The Heart Flashcards
What is the function of arteries in the cardiovascular system?
A) Carry blood toward the heart
B) Carry blood away from the heart
C) Exchange gases and nutrients
D) Store blood for future use
B) Carry blood away from the heart
Explanation: Arteries transport oxygen-rich blood from the heart to the body’s tissues. The only exception is the pulmonary arteries, which carry oxygen-poor blood to the lungs.
Which vessels connect the smallest arteries to the smallest veins?
A) Arteries
B) Veins
C) Capillaries
D) Lymphatic vessels
C) Capillaries
Explanation: Capillaries are microscopic blood vessels that facilitate the exchange of oxygen, carbon dioxide, nutrients, and waste between the blood and tissues.
Which circuit is responsible for carrying oxygen-poor blood to the lungs?
A) Systemic circuit
B) Pulmonary circuit
C) Lymphatic circuit
D) Coronary circuit
B) Pulmonary circuit
Explanation: The pulmonary circuit transports oxygen-poor blood from the right side of the heart to the lungs, where it picks up oxygen and releases carbon dioxide.
Which major artery carries blood from the left side of the heart to the rest of the body?
A) Pulmonary trunk
B) Superior vena cava
C) Inferior vena cava
D) Aorta
D) Aorta
Explanation: The aorta is the largest artery in the body and is responsible for distributing oxygen-rich blood from the heart to the systemic circulation.
The pulmonary circuit delivers oxygen-rich blood to the body’s organs.
A) True
B) False
B) False
Explanation: The pulmonary circuit carries oxygen-poor blood to the lungs for gas exchange. The systemic circuit delivers oxygen-rich blood to the body.
The systemic circuit supplies blood to the lungs.
A) True
B) False
A) True
Explanation: While the pulmonary circuit is responsible for oxygenating blood, the lungs also receive blood supply from the systemic circuit through bronchial arteries.
Veins always carry oxygen-poor blood.
A) True
B) False
B) False
Explanation: Most veins carry oxygen-poor blood, but pulmonary veins are an exception. They transport oxygen-rich blood from the lungs to the left side of the heart.
The _______ is the muscular pump that drives blood through the cardiovascular system.
Heart
Explanation: The heart pumps blood through the pulmonary and systemic circuits, ensuring oxygen and nutrients reach body tissues.
The right half of the heart pumps blood into the _______ circuit, while the left half pumps blood into the _______ circuit.
Pulmonary; systemic
Explanation: The right side of the heart sends oxygen-poor blood to the lungs (pulmonary circuit), while the left side sends oxygen-rich blood to the rest of the body (systemic circuit).
The heart lies within a thick partition called the _______ between the lungs.
Mediastinum
Explanation: The mediastinum is the central compartment of the thoracic cavity that houses the heart, great vessels, esophagus, and trachea.
Which side of the heart supplies blood to the pulmonary circuit?
A) Left side
B) Right side
C) Both sides
D) Neither side
B) Right side
Explanation: The right side of the heart pumps oxygen-poor blood into the pulmonary circuit, which carries it to the lungs for oxygenation.
Which of the following describes the pericardium?
A) A single-layered membrane that encloses the heart
B) A two-layered sac that surrounds and protects the heart
C) The muscular wall of the heart
D) The outermost layer of the heart itself
B) A two-layered sac that surrounds and protects the heart
Explanation: The pericardium consists of an outer fibrous layer and an inner serous layer, which helps protect the heart and reduce friction during heartbeats.
What is the function of pericardial fluid?
A) To help transport oxygen to heart tissues
B) To reduce friction between the pericardial layers during heartbeats
C) To provide structural support to the heart
D) To supply the heart with nutrients
B) To reduce friction between the pericardial layers during heartbeats
Explanation: The pericardial fluid lubricates the heart’s movement, preventing friction that could cause damage to the tissues.
Which part of the heart is responsible for pumping blood into the systemic circuit?
A) Left atrium
B) Left ventricle
C) Right atrium
D) Right ventricle
B) Left ventricle
Explanation: The left ventricle pumps oxygen-rich blood into the systemic circuit through the aorta.
What condition occurs when the pericardium becomes inflamed and causes pain with each heartbeat?
A) Myocardial infarction
B) Pericarditis
C) Endocarditis
D) Cardiac tamponade
B) Pericarditis
Explanation: Pericarditis is inflammation of the pericardium, leading to a painful friction rub as the heart beats.
Most of the heart lies to the right of the median plane.
A) True
B) False
B) False
Explanation: Most of the heart lies to the left of the median plane, with its apex pointing slightly leftward.
The fibrous pericardium is a tough, collagenous sac that is directly attached to the heart.
A) True
B) False
B) False
Explanation: The fibrous pericardium surrounds but is not attached to the heart. It is attached to structures such as the diaphragm and the great vessels.
The pericardial cavity contains 5 to 30 mL of fluid.
A) True
B) False
A) True
Explanation: This small amount of pericardial fluid helps lubricate the heart and minimize friction during contractions.
The superior vena cava drains blood from the lower body into the right atrium.
A) True
B) False
B) False
Explanation: The superior vena cava drains blood from the upper body, while the inferior vena cava drains blood from the lower body.
The heart weighs about _______ grams (or ______ ounces) in an adult.
300 grams (10 ounces)
Explanation: The heart’s weight varies slightly between individuals but is approximately 300 g (10 oz) in an adult.
The space between the parietal and visceral layers of the serous pericardium is called the _______.
Pericardial cavity
Explanation: The pericardial cavity contains pericardial fluid and allows the heart to move without excessive friction.
The _______ pericardium is a simple squamous epithelium that reduces friction, while the _______ pericardium is a tough, collagenous sac that anchors the heart.
Serous; fibrous
Explanation: The serous pericardium secretes pericardial fluid and reduces friction, while the fibrous pericardium provides structural support.
The great vessels entering and leaving the heart include the _______ and _______ vena cavae, the pulmonary trunk, and the aorta.
Superior; inferior
Explanation: The superior and inferior vena cavae return deoxygenated blood to the heart, while the pulmonary trunk and aorta transport blood away from the heart.
Which of the following is the thickest layer of the heart wall?
A) Epicardium
B) Myocardium
C) Endocardium
D) Pericardium
B) Myocardium
Explanation: The myocardium is composed of cardiac muscle tissue and is responsible for the heart’s contractions. It is the thickest layer because it performs the heart’s work.