Plastic dishes for growing cells

There are two kinds of dishes used to grow tissue culture cells.

Those that are designed for adherent cells have been treated chemically to promote cell adhesion and are called tissue culture dishes. Regular petri dishes have not been treated. Tissue culture dishes are much more expensive than regular petri dishes.

Adherent cells must be grown in tissue culture dishes. If they are seeded in regular petri dishes, they will aggregate into clumps that attach poorly to the dish, and cease growth. This is not however a terminal condition. Transfer of the cells to a tissue culture dish will allow them to spread and resume growth.

Non-adherent cells can be grown in any kind of petri dish. The use of tissue culture dishes for these cells is not harmful, it just wastes money.

Dishes come in three commonly used, and one rarely used sizes.

35mm--takes 2 ml of medium. It has an area of 8.55 square cm.
50 mm or 5 cm--takes 5 ml of medium. It has an area of 19.60 square cm.
100 mm or 9 cm--takes 10 ml of medium. It has an area of 56.75 square cm.
135 mm--takes 20 ml of medium. It has an area of 143 square cm.

A well on a 24 well plate has an area of 1.89 square cm and takes 1 to 2 ml of medium.