Cardiovascular System Flashcards
The three main parts of the circulatory system are?
- The blood
- The cardiac muscle/heart
- The blood vessels
What is the purpose of the circulatory system?
To transport oxygen and other substances from the blood to the organs and tissues throughout the body.
What four major components is the blood made up of?
- Red blood cells (RBC’s)
- White blood cells (WBC’s)
- Platelets
- Plasma
What are ‘leukocytes’?
White blood cells (WBC’s)
What are ‘erythrocytes’?
Red blood cells (RBC’s)
How many chambers does the heart have and where is it located?
Four chambers. It’s located between the lungs, slightly left of centre behind your sternum (breastbone). The left lung is smaller to make room for the heart.
Name the receiving chambers of the heart
Atria (plural of atriums)
In a house, you would enter via the Atrium
Atria don’t have to pump as hard as the blood vessels are under pressure and so are smaller than the ventricles.
Name the ejecting chambers of the heart
The ventricles
They ‘vent’ the blood out of the heart. They are harder working chambers and are therefore the largest.
What is the average resting heart rate?
72 bpm
What are the upper chambers of the heart called?
Atria (plural of atrium)
What are the lower chambers of the heart called?
Ventricles
Heart valves are tricuspid, meaning…?
trai·kuh·spuhd
They are made up of three sections
What is pulmonary circulation?
The process of the circulatory system that sends deoxygenated blood from the heart to the lungs to be re-oxygenated to be sent back around the body.
How does blood enter the heart?
Through the left atrium via the pulmonary vein.
What is the difference between veins and arteries?
Arteries carry blood away from the heart, and veins carry blood towards the heart.
Arteries = archery (firing away from your heart!)
What are the three types of blood vessel?
- Arteries
- Veins
- Capillaries
What are the two subcategories of blood vessel?
- Arterioles (small arteries)
- Venules (small veins)
What is the largest artery of the body?
The Aorta
Blood in veins is under pressure and therefore are thick and muscular - true or false?
False.
Veins carry blood to heart and are therefore thinner to allow the blood to flow easier.
What are capillaries for and how do they function?
Capillaries send and collect substances all around the body. They are very thin and semi-permeable to allow diffusion.
Explain the six mechanisms that combine to carry out the venous return.
- Peristalsis within the veins pushes blood along.
- Skeletal muscle pump - contracting muscles push against the vein walls, pushing blood through.
- One way valves to keep the blood from pooling.
- The Right atrium creates a slight vacuum when refilling and helps pull blood into it.
- The diaphragm creates a vacuum in the abdominal cavity which helps draw blood upwards.
- Gravity aids blood that is flowing from above the heart downwards to the right atrium.
Explain vasoconstriction and vasodilation, respectively?
Vasoconstriction is the involuntary process of limiting of blood flow to a certain area of the body via a narrowing of blood vessels. Vasodilation is the process of increasing blood flow to an area wide the widening and relaxing of blood vessels.
What is the definition of ‘blood pressure’
How much force that blood exerts against the walls of the arteries.
What is the optimal blood pressure reading?
120/80 (systolic/diastolic)
What is the blood pressure measurement of someone with hypotension?
<100/<60 (systolic/diastolic)
What is the blood pressure reading of someone with stage 1 hypertension?
140-159/90-99 (systolic/diastolic)
What is the blood pressure reading of someone with stage 2 hypertension?
160-179/100-109 (systolic/diastolic)
What is the blood pressure reading of someone with stage 3 hypertension?
> 180/>110 (systolic/diastolic)
Describe the path of blood flow through the heart.
Oxygenated blood enters the left atrium via the pulmonary vein. Oxygenated blood flows from the left atrium to the left ventricle and into the aorta to be circulated around the body - this sequence is called systemic circulation. The oxygen is used by the cells and organs, producing CO2. Deoxygenated blood is then directed back to the heart via the superior and inferior vena cava where it enters the right atrium and is pumped to the right ventricle.
From the right ventricle, the deoxygenated blood is pumped through the pulmonary artery and sent back to the lungs and where CO2 is diffused into the capillaries for exhalation. This part of the process is called pulmonary circulation.
What is cardiac output and how is it calculated?
Cardiac output is the total amount of blood pumped through the heart in one minute. It is calculated by multiplying heart rate by stroke volume (CO = HR x SV).
Which side of the heart deals with oxygenated blood and which side of the heart deals with deoxygenated blood?
The left side of the heart deals with oxygenated blood and the right side of the heart deals with deoxygenated blood.
