Vocabulary
What is the heart and what does it do?
it is a muscular, hollow organ in charge of pumping blood through the blood vessels
What is blood made up of?
Plasma and blood cells
Where is the heart located?
It is in the thoracic cavity, or the rib cage, between the lungs
How do you call heart contraction and dilation movements?
systole and diastole
How many times does blood pass through the heart?
What are the 3 types of blood vessels?
Arteries, veins, and capillaries
What is the function of blood? (3)
It transports substances, it regulates body temperature, it defends the body
What is the name of the largest artery in the body?
Aorta
What happens during a cardiac cycle?
The blood enters the heart through the veins and leaves it through the arteries. However, the blood vessels remain full of blood at all times, as this is a continuous cycle
What happens to blood in the lungs during pulmonary circulation?
It releases carbon dioxide and picks up oxygen
What is the septum?
It separates the right and left sides of the heart
What is the main function of the circulatory system?
It transports oxygen, nutrients, and waste products throughout the body.
How many chambers does the human heart have? And what are they?
Four (two atria and two ventricles)
How are heart sounds produced?
They occur due to valves closing
Which heart valve prevents blood from flowing back into the left atrium?
Mitral valve
What is the function of valves?
The prevent blood from flowing backwards
What are the different blood cells and their functions?
Red blood cells: They contain hemoglobin (red protein containing iron) that helps transport O2 and CO2
White blood cells: They defend our body against pathogens and tumor cells.
Platelets: They help our blood clot.
What carries blood to the heart and what carries blood away from the heart?
Arteries carry blood away from the heart and veins carry blood to the heart
What are the differences between atrioventricular valves and semilunar valves?
AV valves (tricuspid & mitral) are between the atria and ventricles. They prevent blood from flowing back into the atria.
SL valves (pulmonary & aortic) are between the ventricles and arteries. They prevent blood from flowing back into the ventricles.
What does the pulmonary circuit do vs the systemic circuit?
The pulmonary circuit carries oxygen-poor blood to the lungs and the systemic circuit carries oxygen-rich blood from the heart to the rest of the body.
What do the thin capillary walls allow?
They allow nutrients, gases, and waste to be exchanged between the blood and the cells.
What is the function of the pulmonary artery?
It carries blood to the pulmonary alveoli so that gas exchange takes place
What ends in the left and right atria?
The pulmonary veins end in the left atrium and the venae cavae ends in the right atrium.
What are the 3 stages of the cardiac cycle? Describe them.
Diastole: the atria are relaxed and dilated. This allows the blood to enter the heart.
Atrial systole: the atria contract and the blood flows into the ventricles
Ventricular systole: the ventricles contract forcing the blood into the arteries through the semilunar valves
Explain why blood flow is double and complete
It is double because blood passes through the heart twice and it is complete because oxygen-rich blood and carbon-dioxide-rich blood do not mix because the right side of the heart is completely separated from the left side by the septum