Structures and their involvement in the Transport of Gases
Arteries - Muscular blood vessels that carry oxygenated blood away from the heart to the cells, tissues, and organs of the body
Arterioles – Transfer oxygenated blood from Arteries to Capillaries.
Capillaries -The red blood cells inside the capillary release their oxygen which passes through the thin wall and into the surrounding tissue. The tissue releases its waste products, which passes through the thin wall and into the red blood cells.
Venules – Minute vessels. Transfer deoxygenated blood from Capillaries to Veins. Many venules unite to form a vein.
Veins –Carry deoxygenated blood to the heart.
Structural adaptations of vessels and relationship to Functions.
Arteries
Function: Transport oxygenated blood away from the heart to the cells, tissues, and organs of the body
Structural Adaptations: Arteries have walls which are thick, muscular and elastic.
Relation: The thick, muscular and elastic walls help to withstand blood pressure.
Arterioles
Function: Connects the artery to the capillary. On top of that, it regulates the blood pressure.
Structural Adaptations: Arterioles receive autonomic nervous system innervations and respond to various circulating hormones in order to regulate their diameter, at the same time regulating blood pressure.
Capillaries
Function: Allows oxygen, glucose and other substances transported by blood to be distributed in to its surrounding cells.
Structural Adaptations: Capillaries are only one cell thick for faster diffusion.
Relation:The thin walls enable nutrient and oxygen to move quickly and efficiently from the blood into the cells.
Venules
Function: Connects capillaries to veins.
Structural Adaptations: Has thin walls as pressure exposed is much lesser than arteries.
Veins
Function: Transport deoxygenated back to heart after it has transported oxygenated blood to body. The direction of deoxygenated blood transported by veins is mainly upwards.
Structural Adaptations: Have internal valves along their length to prevent backflow of blood.
Relation: The internal valves are actually one-way “trap doors” that allows blood to go upwards, towards the heart and not dropping back downwards due to gravity.
