some important molecules are too large to pass through the cell membrane.
Hope this helps!
-Payshence
In terms of parasites vs hosts, it is an organism in which the parasite resides and normally feeds + reproduces.
1). it either lowers or increases the activation energy. 2). it modifies the rate of the reaction
Answer:
I think it might be A. I'm not sure.
Answer:
The gene for beta-galactosidase turns off.
Explanation:
The gene that codifies the beta-galactosidase enzyme is part of the <em>lac</em> operon, which also contains two other genes that produce enzymes involved in the metabolization of lactose.
Between glucose and lactose, the bacteria will preferentially use glucose as an energy source. On the other hand, lactose is a dimer, and thus a series of enzymes are needed to process lactose before its use as an energy source.
If there is no lactose present, the genes contained inside this operon are turned off (the operon is repressed).
