Cell :The Building Block of Life — Chapter Summary

Robert Hooke observed cork cells

Robert Hooke observed cork cells in 1665 using a self-designed microscope of about 200 to 300X magnification and named the small box-like compartments

The human eye cannot clearly separate

The human eye cannot clearly separate objects closer than 0.1 mm at 25 cm. Microscopes increase magnification and resolution so tiny structures can be

The cell membrane is a thin

The cell membrane is a thin, selectively permeable boundary about 7 to 10 nanometres thick. Its structure is explained by the fluid-mosaic model, with

Diffusion is the net movement

Diffusion is the net movement of particles from higher to lower concentration. Osmosis is the diffusion of water across a selectively permeable membra

Plant

Plant, fungi, and bacterial cells have a rigid but permeable cell wall outside the membrane. In plants it is mainly made of cellulose, which helps sup