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Peptidoglycan is a mesh of linked sugar chains cross-linked by short chains of amino acids in the cell walls of most bacteria. Its absence from the cell walls of archaea helps distinguish envelope chemistry without confusing either cell wall with a cell membrane. See OpenStax Microbiology, 3.3: cell walls and peptidoglycan.

Plants are eukaryotes. A typical photosynthetic leaf cell has a cell nucleus, mitochondria, chloroplasts, and a cell wall outside its cell membrane. A root cell need not have chloroplasts; the plant's parts specialize for different functions. Plants perform cellular respiration as well as photosynthesis. See OpenStax Biology 2e, 4.3: plant cell organization.

Plasmolysis is withdrawal of the membrane-bounded contents from parts of a cell wall after water loss. A sufficiently concentrated external hypertonic solution, with solutes effectively excluded by the cell membrane over the observation time, can cause this. The cell wall remains; the enclosed material contracts. Plasmolysis is therefore distinct from osmotic lysis, which breaks the cellular boundary during excessive swelling. A return to a less concentrated surrounding chemical solution can reverse plasmolysis if the biological cell remains functional.^[ref]

A protoplast is the living contents of a biological cell bounded by its cell membrane after removal of the cell wall. Removing the cell wall need not immediately destroy the cell membrane; stability depends on the preparation and surroundings. Lysozyme acts on susceptible bacterial peptidoglycan, not on cellulose or chitin, so it is not a universal wall-removal enzyme.

Turgor pressure is the internal hydrostatic pressure above the external pressure in a biological cell. When water enters a walled biological cell by osmosis, expansion loads the cell wall. Rising pressure can oppose further net entry while the cell membrane retains its selective permeability. Mechanical support therefore does not require the cell wall to block water.

As an original mechanical check, idealize a small flat patch of cell wall of surface area $A$ under uniform turgor pressure $\Delta P=P_{\mathrm{in}}-P_{\mathrm{out}}$. Its outward force is $F=\Delta PA$. Doubling $A$ at fixed pressure doubles the load; equal internal and external pressures give zero net pressure load. This is a force balance, not a measured wall strength or a complete model of a curved, growing biological cell. It says nothing about which solutes cross the cell membrane.