BioNinja

Cells that are specialised for material exchange will possess adaptations to increase their surface area

• Cells that are flat and long (squamous) will have a higher SA:Vol ratio than cells that are larger or cuboidal in shape

• Tissues lining absorption surfaces will have ruffled projections (villi), while the cells themselves will possess membranous extensions (microvilli)

Examples of cells that are specialised for material transport include:

• Red blood cells: The cells are thin and flat (biconcave) and have had their nuclei removed to store more haemoglobin (increases oxygen uptake)
  

• Tubule cells: The proximal convoluted tubule of the kidney is folded into villi and the tubule cells possess microvilli to improve selective reabsorption
  

SA:Vol Ratio Adaptations

Red Blood Cells 

Kidney Tubule (Villi)

Tubule (Microvilli)