The circulatory system

circulatory system other names

cardiovascular system

vascular system

circulatory system function

allows blood to circulate around the body

transports nutrients, oxygen, carbon dioxide, hormones, waste and blood cells to and from each cell in the body

what is the circulatory system made up of?

heart, blood, blood vessels

role of the heart

pumps blood around the body by contracting and relaxing

role of the blood

pumped around the body and heart via a network of vessels (arteries, veins and capillaries)

double circulatory system

blood travels through two circuits: the pulmonary and systematic

types of blood vessels

arteries, veins, capillaries

arteries structure and function

carry oxygenated blood at higher pressure from the heart to parts of the body so they have a thick layer of tissue in the wall

veins structure and function

carry deoxygenated blood at lower pressure from the body back to the heart so have less elastic tissue than arteries

valve function

open and close to allow blood flow due to pressure changes in the chambers

stop blood from flowing backwards (backflow)

capillary structure and function

thin walls to allow exchange of compounds e.g. nutrients, glucose, oxygen and co2 between blood and tissues

artery diagram

vein diagram

capillary diagram

how many chambers in mammal and bird hearts?

four

structure of mammal and bird hearts

4 chambers

efficient - does not allow oxygenated and deoxygenated blood to mix

aorta - very elastic and thick as it has to withstand large pressures as it carries oxygenated blood away from the heart

vena cava - transports deoxygenated blood to the heart. not as thick as not under as much pressure (made up of superior and inferior vena cava)

oxygenated colour

red

deoxygenated colour

blue

largest artery

aorta

aorta function

carries oxygenated blood away from the heart

vena cava function

transports deoxygenated blood to the heart

types of vena cava

superior and inferior

types of heart chambers

atria and ventricles

compare atria and ventricles

both have muscular walls that helps them pump blood

ventricles are more muscular as blood must be forced out of the heart at a higher pressure and around the body

left side of heart vs right side

left is more muscular as it pumps blood around the body

right side just pumps blood to the lungs

heart diagram