A scientist studying the effects of radiation on DNA performs an experiment in which she exposes a sequence of nitrogen bases found in DNA to radiation. The DNA before and after the radiation is shown below. Use the evidence to determine whether a mutation has occurred, and if so, interpret that mutation in the answer sheet provided

Before Exposure: ATCGTCA; After Exposure: ATTCGTCA

A. No mutation has occurred to the DNA sequence.

B. A nitrogen base has been deleted from the DNA molecule.

C. A nitrogen base has replaced another nitrogen base in the DNA molecule.

D. A nitrogen base has been added to the DNA molecule.

Structures in cells that carry out specific functions.

Read the following scenario to answer the following question. in some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. applying the biological species concept, the sterility of ligers reveals that a. lions are probably a subspecies of tigers b. tigers and lions are the same species c. a new species called "ligers" is forming d. tigers and lions are separate species

Name the glands associated with human digestive system