Transport In Humans Flashcards
How does heart rate change during exercise
Heart rate increases because more oxygen is needed for aerobic respiration, more aerobic respiration is required to provide ATP for working muscles and oxygen is required for muscles
Describe how a nervous system controls heart rate
Sensors in aorta detect increase in carbon dioxide, it then sends nerve impulses to medulla, the nerve impulse is then sent across the accelerator nerve which then increases heart rate
What is the blood vessels in liver
Hepatic artery and hepatic vein
What blood vessels transport blood to and away from kidneys
Renal artery and renal vein
Function of plasma
To transport blood cells and other substances like amino acids, hormones and waste products in the blood
Function of red blood cells
To transport oxygen through the blood
Functions of white blood cells
Digests pathogens and releases antibodies
Function of platelets
Releases chemicals once exposed by air to create blood clot on an open wound
How are red blood cells specialised
Haemoglobin to bind to oxygen, no nucleus to store more haemoglobin, bi concave shape to increase surface area and decrease distance to centre of cell for a quicker rate of diffusion
Function of arteries
To transport oxygenated blood at high pressure without bursting.
Controls blood flow/pressure by narrowing and widening
Specialisations of arteries
Thick elastic + muscle tissue, thick outer wall and narrow lumen
Function of veins
To carry deoxygenated blood at low pressure and prevent the back-flow of blood
Specialisations of veins
Thin outer wall
Thin elastic and muscular tissue
Wide lumen
Semi-lunar valves
Function of capillary
To provide a short diffusion distance to increase the rate of diffusion
How does your diet affect the risk of coronary heart disease
Eating food with high saturated fats can increase cholesterol and increase risk of fatty deposits
