6. animal transport systems Flashcards
3 main parts that make up the mammalian circulatory system
heart, blood, blood vessels
what is haemoglobin
a protein molecule found in red blood cells in blood vessels
combines with oxygen in high oxygen concentration areas to create oxyhaemoglobin (reversable reaction)
releases oxygen in low oxygen concentration areas
what is a pathogen + 3 types of pathogens
a disease-causing micro-organism - bacteria, fungi and viruses
what is a phagocyte
a type of white blood cell that kills microorganisms by engulfing and digesting them during phagocytosis
what is a lymphocyte
lymphocytes create antibodies which bind to shapes on the surface of pathogens and destroys them
describe the left and right ventricles
left has a thicker wall as it needs to pump blood around entire body
right only has to pump blood to the lungs
function of valves
to ensure that the blood only flows in one direction (prevents the backflow of blood)
describe the flow of blood through the heart
deoxygenated blood from all over the body enters the right atrium is a vein called the vena cava. it is pumped into the right ventricle and then away from the heart in a pulmonary artery - carries the deoxygenated blood to the lungs so it can pick up oxygen
oxgenated blood enters the left atrium in the pulmonary vein. blood flows to the left ventricle and leaves the heart in the aorta - this carries oxygenated blood to the body for aerobic respiration
describe arteries
- carry oxygenated blood away from heart
- thick muscular walls and narrow central channels
- high blood pressure
describe capillaries
- referred to as exchange blood vessels as all exchange of materials between living cells and the blood supply occurs here
- walls are one cell thick (thin walls so faster for diffusion)
- cover very large surface area
describe veins
- carry deoxygenated blood towards the heart
- low blood pressure
- thin walls and wide central channel
- contains valves
