In E. coli, a cluster of three genes called the lac produce enzymes that break apart lactose. To the side of the genes is a region called the , where RNA polymerase binds, and another region called the , where the lac repressor binds.

An organ system consists of a group of organs that performs specific functions necessary for the survival of an organism. humans have eleven different organ systems: integumentary, skeletal, muscular, nervous, endocrine, circulatory, lymphatic, respiratory, digestive, urinary, and reproductive. discuss the function of neurons, the brain and the spinal cord within the human nervous system while explaining the interrelationship of each organ.

During the winter, this species of fox has white fur, but in the summer, it has brown fur. what environmental change may have lead to this fox's fur color? snow cover increase in sun's brightness volcanic eruption global warming

Which of the following would you not find in a bacterial cell? dna cell membrane golgi apparatus ribosomes