B5 The Circulatory System Flashcards
What is the job of the circulatory system?
To move substances around effectively in humans
Why is the circulatory system made up of?
Heart
Blood vessels
Blood
Complete the sentence
Humans and other mammals have a ……. circulatory system
Double
Two circuits joined together
What do each of the circulatory systems do?
In the first one:
The heart pumps deoxygenated blood to the alveoli in the lungs to take in oxygen. Oxygenated blood then returns to the heart.
In the second one:
The heart pumps oxygenated blood around all the other organs of the body. Here the blood gives up its oxygen at the blood cells. The deoxygenated blood then returns to the heart to be pumped out to the lungs again.
See p 69 for a diagram of the circulatory system
.
Complete the sentence
As it is pumped around the body, the blood also travels through …….. near exchange surfaces
Blood vessels
Name two areas where the blood travels through blood vessels near exchange surfaces
Villi (where it picks up food molecules and water)
Kidneys (where it is filtered and urea is removed)
What is the hearts role?
To pump blood around the body
Name the four chambers of the heart
Left atrium
Right atrium
Left ventricle
Right ventricle
What does the heart use it’s four chambers for?
To pump blood around.
What does the heart have to make sure the blood flows in the right direction?
Valves
What happens to the atria when the ventricles contract?
The valves to the atria close and the valves to the blood vessels open.
What do the valves in the heart prevent?
Backflow (when blood flows backwards)
What is the difference between atria and atrium?
Atria is plural, atrium is when there is just one.
See p 69for a diagram of the internal and external structure of the heart
.
Complete the sentence
Blood flows into the two atria from the …….. and the …….
Vena cava
Pulmonary vein
Complete the sentence
The atria ………, pushing the blood into the ……….
Contract
Ventricles
Complete the sentence
The ventricles contract, forcing the blood into the ………. and the ……, and out of the heart
Pulmonary artery
Aorta
Complete the sentence
The blood flows to the organs, including the lungs, through ……….
And returns through ……..
Arteries
Veins
List the 5 stages of the heart pumping blood around the body
- Blood flows into atria from vena cava and the pulmonary vein.
- The atria contract, pushing the blood into the ventricles.
- The ventricles contract, forcing the blood into the pulmonary artery and the aorta, and out of the heart.
- The blood then flows to the organs, including the lungs, through arteries and returns through veins.
- The atria fill again and the whole cycle starts over.
What is the heart made up of?
Cardiac muscle
Complete the sentence
Cardiac muscle contains loads of ………. to provide them with ATP
Mitochondria
Why do cardiac muscles contain loads of mitochondria?
To provide them with ATP.
This release energy needed for the muscle to contract
Complete the sentence
Blood is supplied to the cardiac muscle by two …………, which branch from the base of the ………
Coronary arteries
Aorta
What do the coronary arteries do?
Allow the oxygen and glucose needed for the hearts cells to respire to diffuse through the thick walls of the heart.
Which chamber of the hearts pumps deoxygenated blood to the lungs? (1mark)
The right ventricle
