Transportation of blood,
nutrients, hormones, metabolic waste products from the body and gases:
oxygenated and carbon-dioxide
nutrients, hormones, metabolic waste products from the body and gases:
oxygenated and carbon-dioxide
Factors controlling blood
vessel diameter
vessel diameter
1.
Vasomotor centre of brain: These are associated with
the nerves that supply the blood vessels, stimulates them to constrict (Vaso
Constriction) or Dilate (Vasodialator) based on the feedback to the brain.
Sympathetic branch either increase (Vaso constriction) or decrease
(Vaso-dilation) no parasympathetic branch.
Vasomotor centre of brain: These are associated with
the nerves that supply the blood vessels, stimulates them to constrict (Vaso
Constriction) or Dilate (Vasodialator) based on the feedback to the brain.
Sympathetic branch either increase (Vaso constriction) or decrease
(Vaso-dilation) no parasympathetic branch.
2.
Peripheral resistance: As blood flows through the
blood vessels, they build up resistance. The length of the vessel and viscosity
of blood contribute to its resistance, arterioles provides this resistance
mostly and are called the resistance vessels.
Peripheral resistance: As blood flows through the
blood vessels, they build up resistance. The length of the vessel and viscosity
of blood contribute to its resistance, arterioles provides this resistance
mostly and are called the resistance vessels.
3.
Increased tissue activity: When tissues supply is
increased i.e. it’s activity, the vessel dilate and allows more blood to the
area e.g in exercise. In the other hand, decreased in blood supply, the vessels
constrict to maintain blood pressure. The blood vessel also responds to tissue
damage in the inflammation which there is need to supply blood to vital organ.
Peripheral vessels constrict as in shock to supply the blood.
Increased tissue activity: When tissues supply is
increased i.e. it’s activity, the vessel dilate and allows more blood to the
area e.g in exercise. In the other hand, decreased in blood supply, the vessels
constrict to maintain blood pressure. The blood vessel also responds to tissue
damage in the inflammation which there is need to supply blood to vital organ.
Peripheral vessels constrict as in shock to supply the blood.
4.
Blood supply to the
vessels: All organs in the body needs blood to survive. Where
there is no nutrient and organ, they get the supply from network of capillaries
referred to as VasoVasorum which surrounds the blood vessel. The inner layer
gets their supply from blood that is passing through them by diffusion. A
capillary have a fine network round all the arteries and brings internal respiration.
Blood supply to the
vessels: All organs in the body needs blood to survive. Where
there is no nutrient and organ, they get the supply from network of capillaries
referred to as VasoVasorum which surrounds the blood vessel. The inner layer
gets their supply from blood that is passing through them by diffusion. A
capillary have a fine network round all the arteries and brings internal respiration.
