What structure makes the windpipe stay open, but able to bend

What are charcteristics of lithosphere?

What are two examples of conduction that we use everyday

Pls me i need this ! each cell has genes activated depending on it's job and what kind of cell it is. it is the presence of that causes the repressor protein to fall off and unblock the gene on the lac operon. if a gene is turned on then it is being an additional circular chromosome found in some bacteria that is used in genetic engineering.