Blood Vessels and Heart Flashcards
What is the function of arteries?
Carry blood away from the heart [not a function : high pressure, thick walls, narrow lumen]
What is the function of the veins?
Carry blood to the heart [not function : low pressure, thin walls and wide lumen. Valves present]
What is the function of capillaries?
They exchange materials [eg, glucose and oxygen] between the blood and body cells. [not a function : join arteries and veins. They have very thin walls for glucose and oxygen to diffuse through. The capillary wall is one cell think [endothelium]
What is the inner layer of the capillaries, veins and arteries?
The endothelium
What is the middle layer of the capillaries, arteries and veins?
Muscle and elastic fibres
What is the outer layer of the capillaries, veins and arteries?
Non- elastic collagen fibres
What is the lumen?
The centre of the blood vessel through which blood flows
Place the blood vessels in order of lumen size starting with the widest
Vein, artery, capillary
Place the blood vessels in order of wall thickness starting with the thickest wall
Artery, Vein, Capillary
Place the blood vessels in order of position starting from the heart / Blood flow through a capillary
Artery, [arteriole], Capillary, [Venule], Vein
Which blood vessels have valves? Give their function
Veins. They stop the back flow of blood
What are the two different types of circulation in the body?
Double circulation. Two circuits are : Pulmonary Circuit and Systemic Circuit
What is the pulmonary circuit?
It’s a circuit where blood flows between the heart and lungs
What is the systemic circuit
Circuit in the body where blood flows between the heart and the rest of the body
What is the purpose of the double circulation in the human body?
To keep the oxygenated and deoxygenated blood separate
How is a closed circulation system more efficient than an open?
It is more efficient - it pumps blood around body faster which allows nutrients and oxygen to be distributed faster
Allows the flow of blood to different organs to be increased or decreased - if an animal is running, more blood can be supplied to the leg muscles
In what animal would you find a single circulation?
A worm
What is a portal blood system?
It starts and ends at capillaries
Give an example of a portal blood system?
Hepatic portal vein which carries blood from capillaries in the stomach and intestines to capillaries in the liver
Name the blood vessel that carries blood from the lungs
Pulmonary vein
Name the blood vessel that carries blood to the lungs
Pulmonary artery
Name the blood vessel that carries blood from the kidneys
The renal vein
Name the blood vessel that carries blood to the kidneys?
Renal artery
Name the blood vessel that carries blood from the liver
Hepatic vein
Name the two blood vessels that carry blood to the liver
Hepatic artery and hepatic portal vein
Where does the hepatic portal vein carry blood from and to?
From the stomach/intestines to the liver
What is a pulse?
The expansion and contraction of the wall of an artery due to blood pumping from the heart. It is the same as the rate of the heart beat
What is blood pressure?
It is the force of blood against the walls of arteries
Where is the heart located?
The heart is located in the thoracic cavity, between the lungs slightly to the left
What is the heart made of
Cardiac muscle -an involuntary [not consciously controlled, cannot deliberately control] muscle that does not fatigue
What surrounds the heart?
The pericardium, a double membrane. It contains fluid that reduces friction between the lungs and heart when the heart beats
What protects the heart?
The ribcage
Name the blood vessel that carries blood from the body?
Vena cava
Name the blood vessel that carries blood to the body
Aorta
What separates the left and right side of the heart? What is its function?
Septum. It separates oxygenated and deoxygenated blood so they do not mix.
Name the valve found between the upper and lower chamber of the left of the heart?
Bicuspid valve. It stops blood flowing back from the left ventricle to the left atrium
Why are the walls of the atria thinner than those of the ventricles?
The atria only have to pump blood a short distance to the ventricles. The ventricles have to pump blood to the lungs and the rest of the body
Why is the wall of the left ventricle thicker than the wall of the right ventricle?
The LV has to pump blood all the way around the body while the RV only has to pump blood to the lungs