Flashcards in CH-09 Transport in animals Deck (41)
Describe the human circulatory system, using the words blood vessels, pump and valves.
Circulatory system is a system of blood vessels with a pump and valves to ensure one-way flow of the blood.
What is oxygenated blood?
blood containing a lot of oxygen
Where does blood become oxygenated?
in the lungs
Which side of the heart contains oxygenated blood?
Explain the difference between a double and single circulatory system.
double- blood flows from the heart to lungs and then back to the heart again before travelling to the rest o the body.
single- blood flows directly from the lungs or gills to the rest of the body.
What are the advantages of a double circulatory system
it means oxygenated blood and glucose is transported to body cells faster, at higher pressure as the blood pressure that is lost in through small capillaries in lungs can be raised again before sending it to the body
Which part of the heart receives blood from a.LUNGS b.THE BODY
a. left atrium
Whare are the one-way valves found in the heart?
between the atria and the ventricles
Which structure in the heart separates oxygenated blood from deoxygenated blood?
Which parts of the heart pump blood into a. PULMONARY ARTERY b.THE AORTA
Why do ventricles have thicker walls than the atria?
They contain more cardiac muscle, which can therefore provide a greater force they contract. This is needed to pump the blood around the body.
Why does the left ventricle have a thicker wall than right ventricle?
It contains more cardiac muscle, needed to produce more force to pump blood all around the body rather than just to the lungs.
List three ways in which the activity of the heart can be monitored.
With an ECG, by measuring pulse rate, listening to the sound of valves closing.
Explain why your pulse rate is the same as your heart rate.
The pulse is the regular expansion of arteries, caused by blood surging through at high pressure each time the ventricles contract
Why does your heart need to beat faster when you do exercise?
to move oxygenated blood to the muscles more quickly, to supply the oxygen they need to release energy from glucose, by respiration.
Where and what is the pacemaker?
It is a patch of muscle in the right atrium which sets
Explain what makes your heart beat faster when you exercise.
Extra CO2 dissolves in blood plasma, reducing its pH. This is sensed by receptors in the brain, which increases the frequency of nerve impulses sent to the pacemaker.
Describe and explain the action of the atrioventricular valves during ventricular systole.
The valves are pushed closed by the high pressure of the blood in the ventricles. This prevents blood from flowing back into the atria.
What type of blood vessels carry blood
a. away from
b. towards the heart?
Why do arteries need strong walls?
The pressure of the blood in arteries is high and pulsing, so the strong walls are needed to withstand the pressure.
Why do arteries have elastic walls?
The elastic walls allow the arteries to expand with each pulse of pressure - produced by the heart and then recoil in between pulse; if they could not do this they might burst.
what is the function of capillaries?
capillaries deliver blood, containing oxygen and nutrients, very close to every cell in the body.
Why do veins have a large lumen?
A large lumen provides less resistance to blood flow, needed to because blood pressure in the veins is low.
How is blood kept moving in the large veins of the legs?
Skeletal muscles in the legs squeeze inwards on the veins when the muscles contract, pushing blood along inside them.
What is unusual about the blood supply to the liver?
It is supplied with blood by two vessels- the hepatic artery and the hepatic portal vein.
List five substances that are transported in plasma.
Five from water glucose, vitamins, minerals (inorganic ions), urea, hormones, fibrinogen, antibodies (and others )
What is the function of red blood cells?
Transportation of oxygen
What is unusual about the structure of red blood cells?
have no nucleus
have biconcave shape
What is haemoglobin?
a red pigment absorbs and releases oxygen; a protein found inside red blood cells