Why is an experiment called a controlled study?

Which of the following was a characteristic of a dromaeosaur? modified front claw grasping with their forelimbs both a and b none of the above

Residential construction is expanding in florida, the expansion has caused fragmentation of habitats, one of the results of the increased construction is a decrease in the number of large predators such as the coyote, black bear and pool panther, which will be the most immediate local result of this fragmentation? 1)large predators will become extinct 2)decrease in middle sized predators 3)increase in population of top carnivores 4)increase in population of prey species

How do the evolutionary chart and the video support the claim that all living things are made up of cells?