Biology 3.3 3.4 3.5 Flashcards
what are two waste products the circulatory system carries
carbon dioxide and urea
what is a double circulatory system
when blood goes through the heart twice in one circuit
where does the blood go in the first circuit
through the lungs to become oxygenated
where does blood go in the second circuit
to the rest of the body, giving oxygen to the cells and coming back to the heart to go round again and be oxygenated
what are the walls of the heart made of
muscle tissue
what are the four chambers of the heart
the right and left atria (above) and the right and left ventricles (below)
what are the main blood vessels leading in and out of the heart
vena cava, aorta, pulmonary artery, pulmonary vein
what do valves do
prevent backflow of blood
what do the coronary arteries do
branch off the aorta and give the heart the oxygenated blood it needs
how does blood flow through the heart
into the two atria from the pulmonary vein and the vena cava. the atria then contract, pushing the blood into the ventricles. the ventricles contract pushing the blood into the pulmonary artery and aorta.
how do you calculate blood flow
volume of blood/number of minutes
what is blood
a tissue made up of red blood cells, white blood cells, platelets and plasma
what is the function of the blood
to transport substances around the body
what is the job of red blood cells
to transport oxygen
what do red blood cells look like
a biconcave shape for a larger surface area and a pigment called haemoglobin for carrying oxygen and no nucleus to help carry more oxygen
