In gene therapy, a defective gene is replaced by a virus carrying a normal gene. If successful, 1. The cells divide and daughter cells express the normal gene.
2. The cells are recycled after death.
3. The cells lack a nucleus.
4. The cells do not produce the normal gene.

What pattern of migration do whales follow?

Which event would lead to primary succession of a forest?

Which statement correctly describes other ways in which nebulae and stars are different? a. a star always has a higher density than a nebula. b. stars can form inside a nebula but a nebula can never be produced by any star. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star. reset submit