In 1831, charles darwin visited the galapagos islands. while observing the giant land tortoises that lived on these islands, darwin noted that the shape of the tortoise shell varied depending on which island the tortoise lived. tortoises on one island had round shells, for example, whereas tortoises on a neighboring island had more flattened, saddle-shaped shells. which statement best summarizes darwin's explanation for these differences?
a) random mutations caused the shape of the shells to fluctuate periodically.
b) the shape of the tortoise shell varied because the predators on the islands were different.
c) the particular shape of the shell was best suited for the island on which the tortoise was living.
d) tortoises who used their shells in special ways caused the shells to become larger, rounder, or flatter.

Need an answer asap 45 points and brainlest to the first person to answer why do scientific theories, such as biological and chemical evolution, represent the strongest explanation of the changes observed in the fossil record. must be in sentence form how can scientific theories on evolution and the fossil record change over time? must be in sentence form

Astudent from one of the research labs is having trouble preparing a slide for examination and photographing. the bacterial slide that he has brought to you was prepared using a commercially purchased stain. he has asked for your in determining what he is doing wrong so that he can change the lab protocols and continue on with his project. after examining the slide under oil immersion, you determine that no bacteria are present even though the student is able to show you the culture he used to make that slide that has visible growth in the liquid medium. which of the following statements does not explain the fact that there are no bacteria present on the student’s slide? by not allowing a glass slide to completely air dry before heat fixation, the flame will cause the surrounding water to boil and this will damage the bacterial cell. overheating during the fixation step boiled the water within the bacterial cells and resulted in the cells bursting. insufficient heating of the slide did not drive out the thin layer of water and this resulted in minimal bonding between the bacteria and the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide.

3differences between bacteria and other 2 cells