1.
The human heart weighs ________________________________________.
Correct Answer
B. Under a pound
Explanation
The correct answer is "under a pound" because the average weight of the human heart is approximately 11 ounces, which is less than a pound. The heart is a muscular organ responsible for pumping blood throughout the body, and despite its small size, it is incredibly strong and vital for maintaining overall health and functioning.
2.
What is the heart's function (job)?
Correct Answer
B. To feed all the cells in your body
Explanation
The correct answer is "To feed all the cells in your body." The heart's main function is to pump oxygenated blood to all the cells in the body and remove waste products. It does not directly help with breathing, as that is the role of the lungs.
3.
The heart is a solid organ.
Correct Answer
B. False
Explanation
The heart is not a solid organ. It is a muscular organ that pumps blood throughout the body. It is made up of different chambers and valves, allowing it to contract and relax to pump blood effectively. Therefore, the statement "The heart is a solid organ" is incorrect.
4.
What is the endocardium?
Correct Answer
B. Is the lining of the heart on the inside
Explanation
The endocardium refers to the lining of the heart on the inside. It is the innermost layer of tissue that covers the chambers of the heart and valves, providing a smooth surface for blood flow and preventing clotting.
5.
How many chambers are there in the heart?
Correct Answer
C. 4
Explanation
The heart has four chambers: two atria and two ventricles. The atria receive blood from the body and lungs, while the ventricles pump the blood out to the rest of the body. The separation of chambers allows for efficient circulation and prevents oxygenated and deoxygenated blood from mixing.
6.
What are the two top chambers called?
Correct Answer
E. Both A & B
Explanation
The two top chambers of the heart are called the left atrium and the right atrium. The atria are responsible for receiving blood from the body and lungs, and then pumping it into the lower chambers of the heart. Therefore, the correct answer is "Both A & B" because both the left atrium and the right atrium are the top chambers of the heart.
7.
The three types of blood vessels are the veins; arteries; and capillaries.
Correct Answer
A. True
Explanation
The statement is true because veins, arteries, and capillaries are indeed the three types of blood vessels. Veins carry deoxygenated blood back to the heart, arteries carry oxygenated blood away from the heart to the rest of the body, and capillaries are the smallest blood vessels that connect arteries and veins, allowing for the exchange of nutrients and waste products between the blood and tissues.
8.
The function of an artery is
Correct Answer
B. To take blood out of the heart
Explanation
Arteries are blood vessels that carry oxygenated blood away from the heart to various parts of the body. They have thick, elastic walls that help maintain blood pressure as they transport blood to tissues and organs. Therefore, the correct answer is "to take blood out of the heart."
9.
How many miles of blood vessels do we have in our bodies?
Correct Answer
D. 60,000 miles
Explanation
Our bodies have approximately 60,000 miles of blood vessels. This extensive network of blood vessels is responsible for transporting blood throughout the body, delivering oxygen and nutrients to cells, and removing waste products. The circulatory system is vital for maintaining the overall health and functioning of the body.
10.
Which artery brings blood to the lungs?
Correct Answer
C. Pulmonary Artery
Explanation
The pulmonary artery is the correct answer because it is the artery that carries deoxygenated blood from the heart to the lungs. It branches off from the right ventricle of the heart and transports the blood to the lungs, where it is oxygenated. After oxygenation, the blood returns to the heart through the pulmonary veins. The tricuspid artery and pulmonary valve are not correct answers as they do not exist in the human anatomy.
11.
The biggest vein in the body is
Correct Answer
C. Vena cava
Explanation
The vena cava is the correct answer because it is the largest vein in the body. It is responsible for carrying deoxygenated blood from the body back to the heart. There are two main types of vena cava: the superior vena cava, which receives blood from the upper body, and the inferior vena cava, which receives blood from the lower body. Both play a crucial role in the circulatory system, making the vena cava the largest and most important vein in the body.
12.
The heart is made of fat?
Correct Answer
B. False
Explanation
The heart is not made of fat. It is primarily made up of cardiac muscle tissue, which is a specialized type of muscle that contracts to pump blood throughout the body. While there is a layer of fat surrounding the heart to provide cushioning and protection, the heart itself is not composed of fat.
13.
Blood goes through the pulmonary valve before it goes through the mitral valve.
Correct Answer
A. True
Explanation
Blood goes through the pulmonary valve before it goes through the mitral valve because the pulmonary valve is responsible for directing blood flow from the right ventricle to the pulmonary artery, which carries deoxygenated blood to the lungs for oxygenation. After oxygenation, the blood returns to the left atrium of the heart and then passes through the mitral valve to enter the left ventricle, which pumps oxygenated blood to the rest of the body. Therefore, the blood must pass through the pulmonary valve before reaching the mitral valve.
14.
Capillaries are the smallest blood vessels.
Correct Answer
A. True
Explanation
Capillaries are indeed the smallest blood vessels in the human body. They are responsible for connecting the smallest arteries (arterioles) to the smallest veins (venules). Capillaries play a crucial role in facilitating the exchange of oxygen, nutrients, and waste products between the blood and the surrounding tissues. Due to their small size and extensive network, capillaries allow for efficient diffusion and transport of substances throughout the body.
15.
It is the valve's job to not let blood go backwards once it has gone through a valve.
Correct Answer
A. True
Explanation
Valves in the circulatory system prevent the backward flow of blood. Once blood has passed through a valve, it closes to ensure that blood does not flow back in the wrong direction. This mechanism is crucial for maintaining the efficiency and directionality of blood flow throughout the body. Therefore, the statement is true.