Microbial Armor: Bacterial Cell Wall Structure

If some bacteria have thick walls and others have thin walls, then they will soak up dye differently. If the dye turns them different colors, then scientists can identify the bacterial cell wall structure.

If a bacterium turns purple during a stain test, it is "Gram-positive." If the purple dye stays trapped, then it is because the cell has a very thick, absorbent wall.

If a cell moves from a salty ocean to a fresh lake, the pressure changes. If the wall is strong enough to handle those changes, then the bacterium can survive in many environments.

If a cell has no bones on the inside, then it needs support from the outside. If the wall provides that support and keeps the cell from being crushed, then it is like an external skeleton.

If a single-celled organism lives in a messy environment, then it needs a hard outer layer to stay safe. If that layer is stiff, then it also forces the cell to stay in a specific shape.

If the wall is meant to be a protective shield for the whole cell, then it must be the outermost layer. If it were inside the membrane, then the membrane would be unprotected.

If the inside of a cell is saltier than the water outside, then water will rush in. If there is no strong wall to hold that water back, then the pressure will pop the cell like a balloon.

If trees use cellulose and bacteria use peptidoglycan, then they are made of different materials. Therefore, the bacterial cell wall structure is not the same as wood.

If the wall needs to be strong like a mesh fence, then it uses a combination of sugars and proteins. This specific biological material is named peptidoglycan.

If a bacterium cannot finish building its "house," then the structure will collapse. If the medicine prevents the peptidoglycan from linking together, then the wall fails and the cell dies.

If a cell were completely sealed off by its wall, then it would starve to death. If the cell is alive, then the bacterial cell wall structure must be "leaky" enough to let nutrients in.

If a cell needs to make a wall, it needs instructions. If the DNA holds all the instructions for the cell's parts, then the DNA provides the "recipe" for the wall.

If a knight wears metal plates to stay safe from swords, then a bacterium wears a wall to stay safe from its environment. This "suit" is the cell's primary defense.

If you put a balloon inside a cardboard box, the balloon takes the shape of the box. If the wall is like the box, then it forces the bacterium to be that specific shape.

If the wall must hold a shape, it is rigid and strong. If the cell still needs to "breathe" and eat, then the wall must have holes to let food in.

If the wall is made of linked proteins and sugars, then it looks like a net or mesh. If it lets things pass, then it has pores. It will not have human-like organs.

If water enters a cell, it creates pressure; a wall stops the cell from popping. If the cell needs to be a specific shape (like a pill or a ball), the wall acts as the mold.

If a wall keeps out harmful chemicals and physical bumps, then it is performing the job of a shield.

If a bacterium has a thin wall and a second "skin" on the outside, then it doesn't hold the purple dye and turns pink. This type is called Gram-negative.

If you touch your own skin, it is soft because animal cells lack walls. If you look at bacteria, they are rigid; therefore, the presence of a wall is a major difference.