The Circulatory System Flashcards
What are the components of blood
White blood cells
Red blood cells
Platelets
Plasma
Platelets
No nucleus
Clump when blood vessel is damaged and clot
Plasma
Liquid which transports : Carbon dioxide from cells to lings Glucose and digested food products from small intestine to cells Waste products from liver to kidneys Hormones to organs Antibodies to fight disease
White blood cells
Protect body against disease
Some have flexible shape- engulf microorganisms (phagocytes)
Others produces antibodies to attack microorganisms (lymphocytes)
Red blood cells and adaptions
Transport oxygen from lungs to tissues
Large surface area to volume ratio
Small and flexible to pass through capillaries
No nucleus so can be packed with haemoglobin
The shape increases surface area for transferring oxygen
How is haemoglobin used to release oxygen for cell diffusion
Oxygen diffuses from lungs into the blood
Haemoglobin binds with oxygen forming oxyhemoglobin
Blood then pumps around body where opposite happens in tissues and cells
Oxygen is released by break down of oxyhemoglobin to diffuse into cells
Arteries
Blood transported away from heart
Thick walls of fibres to cope with high pressure
Lumen is small compared to thickness of walls
No valves
Veins
Transport blood towards the heart
Thinner walls
Lumen is large compare to wall thickness
Valves to prevent back flow of blood
Capillaries
Narrow vessels connecting arteries to veins
Permeable walls allows exchange of substances between cells and blood
Walls are one cell thick
The human circulatory system is double and consists of two loops
What is the function of each loop and what are they called
Pulmonary carries blood from heart to lungs and back to the heart
Systemic carries blood from heart to other body parts and back to the heart
In which blood vessel is the blood pressure strongest
The arteries (blood flow away from the heart) weaker in the veins (blood flow to the heart)
This pressure difference causes blood to flow
What is the advantage of a double circulatory system
Blood is pumped at higher pressure (recieves two boosts from the heart for every complete circuit)
This results in greater blood flow rate to tissues
In the capillaries what substances are exchanged between cells and blood
Oxygen and food are supplied to the cells
Carbon dioxide and waste are removed from the cells
What are the lower chambers of the heart called
Why are they large and muscular
Ventricles
They contract to pump blood out of the heart
Where does the right ventricle pump to
The lungs
