(Applied Anatomy & Physiology) Cardio-Respiratory System Flashcards
What are some functions of the cardiovascular system?
- controlling temperature
- blood clotting
- transport
Why is blood clotting important?
It helps open wounds to heal and prevents them from becoming infected.
What are arteries?
Arteries are a type of blood vessel.
What characteristics do arteries have which help it do its job?
Arteries are elastic at we and thick. This lets them cope with the high pressures at which blood is pumped away from the thick, muscular ventricles of the heart.
They also have the thickest walls and largest external diameter of all blood vessels. They have a slightly smaller lumen (internal diameter)
Think of the walls of arteries like elastic bands. They can stretch to cope with the high pressure from the heart but then return to their original shape and size m. This prevents them from bursting.
What is the job of the veins?
Veins carry blood towards the heart (mostly deoxygenated blood)
How are veins structured?
They have a large internal diameter (lumen) but think walls as the pressure inside them is low. Veins have valves to prevent the back flow of blood, which is a possibility due to the lower pressures. This means they do not have a pulse.
What are capillaries?
Capillaries are a tiny network of blood vessels that link the arteries and veins.
What is the structure of the capillaries?
They are very small and can only let 1 red blood cell through at a time.
They are only 1 cell thick.
What is the function of the Capillaries?
They make diffusion easier (shorter distance for oxygen or carbon dioxide to travel)
What does vasoconstriction cause?
Causes space in blood vessels to get smaller, letting less blood through. During exercise, blood vessels leading to the stomach will construct (get narrower) to reduce blood bf low to ‘non-essential’ organs.
What does vasodilation cause?
Causes the space in blood vessels to get larger, letting more blood flow through. During exercise, blood vessels in the working muscles dilate (get wider) to allow more blood in.
What is the vena cava?
A vein that returns deoxygenated blood back to the right atrium
What does the Pulmonary artery do?
Carries deoxygenated blood from the right ventricle to the lungs.
What does the Pulmonary vein do?
Carries oxygenated blood from lungs back to the left atrium.
What is the Aorta?
The largest artery that carries oxygenated blood from the left ventricle to the rest of the body.
Why is the atria small?
They are small because the body only needs them to pump blood into the next change of the heart (ventricle).
What is the function of the right atrium?
It receives deoxygenated blood from the rest of the body through the superior vena cava.
What is the function of the of the left atrium?
It received oxygenated blood from the lungs through the pulmonary vein.
What is the structure of the right ventricle?
It has thinner walls and is less muscular. This is because less pressure is needed to pump the deoxygenated blood into the lungs via the pulmonary vein.
What is the structure of the left ventricle?
It has a thick, strong wall. This is because it needs to pump oxygenated blood to the entire body at a high pressure to make sure it gets there.
What is the name of the wall that separates the right and left ventricles?
The septum
How does deoxygenated blood travel during the cardiac cycle?
°Deoxygenated blood enters the right atrium from the vena cava (from the body)
°The atrium contracts and blood is pushed through a valve (to prevent backflow) into the right ventricle.
°The right ventricle then contracts and pumps blood through the pulmonary artery.
°The pulmonary artery carries the deoxygenated blood to the lungs where gaseous exchange takes place.
How does oxygen blood travel in gaseous exchange?
Gaseous exchange in the lungs causes the blood to become oxygenated.
°Having been oxygenated in the lungs, blood then travels along the pulmonary vein back to the heart.
°Oxygenated blood enters the left atrium from the pulmonary vein.
°The atrium then contracts and pushes the oxygenated blood through another valve (to prevent backflow) and into the left ventricle.
°The left ventricle then contracts to pump blood into the aorta at a high pressure.
What is the pathway of air?
- Air is taken in through the mouth or nose
- The air flows through the trachea (windpipe)
- When the trachea reached the lungs, it divides into 2 branches called the bronchi. Each bronchi enters a lung.
- In the lungs, the bronchi divide further into many bronchioles. These bronchioles are less than 1mm in diameter m.
- At the end of the bronchioles are a cluster of alveoli. These are tiny air sacs where gaseous exchange takes place.
