Answer:
caves and sinkholes
Explanation:
caves and sinkholes are associated with karst topography because they are some of the main features.
I believe the appropriate answer is, short amino acid chains, NAG, NAM, and some lipid proteins.
Peptidoglycan is also known as Murein, it is a polymer consisting of sugars and amino acids that form a mesh-like layer outside the plasma membrane of most bacteria, forming the cell wall. The sugar component consist of alternating residues of β-(1,4) linked N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM),
A cell membrane can me compared to a wall, one that is flexible and malleable but strong enough to repel unwanted things from the cell. it also keeps the cell together in its shape and form
