Organisation 2 (B2) Flashcards
what does an Artery do
carry blood AWAY from the heart
what does a vein do
carry blood TO the heart
what does a capillary do
connects veins and arteries
describe an artery
thick muscular walls
small lumen
carry blood under high pressure
carry oxygenated blood
describe a vein
thin walls
large lumen
carry blood under low pressure
carry deoxygenated blood
describe a capillary
one cell thick to allow diffusion
carry blood under very low pressure
is blood a tissue
yes
what does blood contain
plasma in which blood cells, white blood cells and platelets are suspended
how much of the blood does plasma make up
55%
how much of the blood do red blood cells make up
45%
how much of the blood do white blood cells make up
less than 1%
how much of the blood do platelets make up
less than 1%
what colour is plasma
pale yellow fluid
what does plasma do
transports CO2 , hormones and waste
what do red red blood cells carry
oxygen
describe red blood cells
large surface area
no nucleus
what are white blood cells part of
the immune system
what function to white blood cells carry out
some produce antibodies others surround and engulf pathogens
what do platelets do
clump together and form blood clots
what does the trachea do
carries air to/from the lungs
what do the bronchioles do
carries air to/from the alveoli
what do the alveoli do
site of gas exchange in the lungs
what do the capillaries do
allow gas exchange between into/out of the blood
what do the trachea have to protect the airway
rings of cartilage
what do bronchioles do to reach all the air sacs
split into multiple pathways
how are alveoli adapted for gas exchange
maximises surface area for efficient gas exchange
what happens in the capillaries
oxygen diffuses into the blood and carbon dioxide diffuses out
different structures in the heart have
different functions
right ventricle
pumps blood to the lungs where gas exchange takes place
left ventricle
pumps blood around the rest of the body
pacemaker (in the right atrium)
controls the natural resting heart rate
what can be added to correct irregular heart rates
artificial electric pacemakers
coronary arteries
carry oxygenates blood to cardiac muscle
heart valves
prevent blood in the heart from flowing in the wrong direction
what does the heart pump to the lungs
low oxygen/high carbon dioxide blood
features of the heart
left ventricle
right ventricle
coronary arteries
the heart is an organ that pumps blood around the body in a ________ ______ _____
double circulatory system
