In the presence of lactose, how long does it take for the lac operon to be expressed? (A) when glucose is more than lactose concentration
(B) when lactose equals glucose concentration
(C) as long as lactose is more than galactose concentration
(D) as long as lactose is more than glucose concentration

What would happen to the nutrients in an ecosystem if decomposers, such as bacteria, didn’t exist there?

What is the significance of the protein-lined pits? a. protein attracts other proteins needed for atp synthesis within the cell. b. protein-lined pits are able to transport one molecule at a time down the concentration gradient within the cell. c. the polarity of proteins allows other polar molecules to attach and be transported in the cell by transport channels. d. receptors within the pits allow ligands to fuse and be transported into the cell by endocytosis.

Nephrons, the functional unit of kidneys, are responsible for formation of urine. the sentences describe situations that are the result of problems in the urine formation process. for the nephron shown below, match each situation to the step in the urine formation process where the problem lies.