Although trees like this one begin life as a seed, throughout growth and development the cells of the organism continually change. As a mature tree, several layers of cells in the secondary xylem or wood of the trunk are

The idea of spontaneous generation was disproved by in a experiment involving jars of meat

Which of the following statements about archaea and bacteria is true? a. neither is single-celled. b. they both have nuclear membranes. c. neither reproduces by binary fission. d. they both lack a nuclear membrane.

Study the picture of the ocean. which is the best example of an organism’s niche shown in the picture? a. the environment contains several of the same species of coral. b. the shallow area of the ocean meets the needs of the coral and the fish. c. the ocean has fish and coral that live in the same area. d. the coral take in food from the water and provide shelter for the fish.