Answer:4 jello boxes
Explanation: check attached photo for explanation
It relates to the meaning of the pores of skin because it lets in and out only certain things.
I hope this helps, Sweetie.
A layer of smooth cartilage at their ends, which cushions the bones and prevents them from rubbing directly against one another. The whole joint is also enclosed in a synovial capsule, which is full of synovial fluid. The synovial fluid acts like the oil in an engine, lubricating the joint and preventing the cartilage from becoming worn down.
I'm not sure but I thinks the first animal that produce bacteria is Pig.