A type of trilobite is used as an index fossil. These fossils were made around 540 million years ago. A scientist finds a trilobite fossil within layer 3 in the diagram (picture).

What can the scientist conclude from this finding?

A. Fossils from layer 9 are the newest in the diagram.

B. All the fossils in this diagram are at least 540 million years old.

C. Layer 1 has the newest fossils in the diagram.

D. Fossils in layer 5 are less than 540 million years old.

The tasmanian devil, a marsupial carnivore, is facing extinction due to devil facial tumor disease (dftd) which causes bulging cancerous lumps and lesions to erupt around the face and neck — often causing enough deformation to make seeing or eating difficult. dftd has evolved into a contagious cancer, a trait that is unique among cancers. devil mating behavior involves biting around the head and neck, allowing cells from one individual — especially cells from the crumbly dftd tumors — to be transferred to the wounds or face of a new individual. this marsupial was once found across australia, but sea levels rose, isolating the tasmanian population, while the australian population went extinct. what would be an outcome of genetic isolation that is likely to have impacted the spread of dftd? a) reduced territory puts diseased individuals in greater contact with non-diseased ones. b) inbreeding results in less variation in facial features so the cancer is generally fatal. c) genetic isolation has made it difficult for scientists to develop a vaccine against dftd. d) the lack of genetic variation in the immune system of tasmanian devils minimizes resistance to the disease.

If jane has the blood type ab and marries john who has type o blood what are the possible phenotypes of their first kid?

According to the cell theory, which describes cells? a. all organisms are composed of multiple cells. b. all cells have the same structure and function. c. cells are found in everything on earth. d. living organisms are not created spontaneously