Ascientist observes fossil evidence that leads her to believe that certain organisms have a common ancestor.

which observation most likely led to this conclusion?

she observed older fossils that contained many of the same minerals as the newer ones.
she found skeletons of modern organisms in the same area as fossilized organisms.
she observed a fossil with skeletal structures similar to certain modern organisms.
she found several fossils in rock layers directly below other fossils of similar size.

Mouse liver cells were homogenized and the homogenate subjected to equilibrium density-gradient centrifugation with sucrose gradients. fractions obtained from these gradients were assayed for marker molecules (i. e., molecules that are limited to specific organelles). the results of these assays are shown in the figure. the marker molecules have the following functions: cytochrome oxidase is an enzyme involved in the process by which atp is formed in the complete aerobic degradation of glucose or fatty acids; ribosomal rna forms part of the protein-synthesizing ribosomes; catalase catalyzes decomposition of hydrogen peroxide; acid phosphatase hydrolysis monophosphoric esters at acid ph; cytidylyltransferase is involved in phospholipid biosynthesis; and amino acid permease aids in transport of amino acids across membranes. a) name the marker molecule and give the number of the fraction that is most enriched for each of the following cell components: lysosomes; peroxisomes; mitochondria; plasma membrane; rough endoplasmic reticulum; smooth endoplasmic reticulum.

An example of a trait that would be considered acquired and inherited is a. a cleft chin b. muscle tone c. scar tissue d. freckled skin

What function does a limb serve in each animal how are the limb bones of the four animal similar based on the similarities what can be inferred about the evolution of the poor animals