The biconcave shape of erythrocytes increases the surface area available for oxygen absorption.
The flexible cell membrane and nuclear membrane allow neutrophils to exit capillaries and enter infected tissues.
Sperm cells are motile – their tail helps propel them forward in search of an egg to fertilise.
The root hair is an extension of the cytoplasm, increasing the surface area of the cell in contact with the soil to maximise absorption of water and minerals.
The cilia move in a coordinated way to push dirt and microbes away from the lungs
The structure of squamous epithelium
The tall and thin palisade cells are densely packed together for the maximum absorption of light.
When the guard cells are turgid the stoma is open, when they are flaccid the stoma is closed.