Circulatory System: introduction and the heart Flashcards
Why do humans need the circulatory system? (note: this is not what does the circulatory system do)
Humans need a method of transportation for materials and they need to transport these between their cells
What are the main functions of the circulatory system? (key word: transport)
To get food and oxygen to every cell in the body. It also acts as a waste product elimination service. It’ll eliminate Co2 and urea from the body. It’ll transport it to where it’s removed in the body.
What does the circulatory system include?
Heart, blood vessels and blood
Humans have a double circulatory system. What happens in the first circuit (hint: right side)?
1st circuit: right ventricle pumps deoxygenated blood to the lungs to take in oxygen and once it becomes oxygenated again the blood goes back to the heart.
Humans have a double circulatory system. What happens in the second circuit (hint: left side)?
Left ventricle pumps oxygenated blood around to all other organs of the body. Blood with give up all its oxygen to the cells and now the blood is deoxygenated so it goes back to the heart to be pumped to the lungs
True or false: the heart isn’t an organ. Why?
False, the heart is a pumping organ.
What’s the heart’s job?
To keep blood flowing around the body
What do the walls of the heart do and what are they made of?
Heart walls are made of muscle tissue and they contact to pump the blood that enters and exit the heart
The heart has 4 chambers. What are they?
Right and left atria, right and left ventricles.
The heart has four main blood vessels which carry blood in and out of the heart. What are they and which ones carry blood into the heart and which ones out?
Pulmonary vein and vena cava carry blood in and the aorta and the pulmonary artery carry blood out
What are the uses of valves?
They exist to stop blood from flowing the wrong way. They exist to prevent backflow
What do coronary arteries do? Why do they exist?
The heart needs its own supply of oxygenated blood and the coronary arteries act as a blanket around the heart. They branch off the aorta and surround the heart, making sure it gets oxygenated blood.
Explain in full detail how blood flows through the heart. Like it’s journey.
– blood flows into the two atria from the vena cava and the pulmonary vein.
– atria contract, pushing blood into the ventricles
– ventricles contact, forcing blood into the aorta and pulmonary artery.
– blood flows either to the lungs or to all the organs of the body through the artery and return to heart through veins
– atria fill again and the whole cycle starts over
What is an artificial pacemaker?
It’s a little device that can be inserted into your body and it’s there to keep your heart beating regularly.
What are our body’s natural pacemakers?
A group of cells in the wall of the right atrium wall.
