Barry is applying the principles of relative dating to a building that has been constructed. analyzing a section of the building, barry says that the lowest part of the section must have been constructed the parts above it were constructed. he bases this conclusion on the principle of . also, looking at a crack forming in the building wall, he says that the crack must be the wall. barry used the principle of to arrive at this conclusion.

Which of the following statements is true of enzymes? a)they dont provide an active site for substrates to bind in a reaction b)they act on a specific type of substrate in a reaction c)they unusable after a reaction d)they change shape after a reaction

Asmall number of finches are removed randomly from the wild and placed in a protected bird area. they are given as much food as they need and have plenty of space. why would natural selection not occur in this population? a. there is no reason for genetic mutation to occur. b. the birds compete for limited resources, c. the population has not reached carrying capacity. d. there is no genetic variation in the finches.

On a recent expedition to a remote region of northern canada, scientists uncovered skeletal remains from about 100,000 years ago. surprisingly, all the skeletal remains, which included many species from differing biological families and spanned about two thousand years, showed evidence of experiencing temperatures in excess of 1000 degrees fahrenheit (or 538 degrees celsius). which of the following, if true, best explains the apparent paradox between the cold environment and the evidence of the bones experiencing hot temperatures? (a) chemical changes that naturally occur during the process of decay in only one north canadian species produce the same evidence of the species' skeletons being exposed to hot temperatures as the expedition scientists found. (b) a little over 103,000 years ago, a large fire is known to have occurred in northern canada. (c) strong evidence exists that as early as 70,000 years ago, homo sapiens around the world relied heavily on fire to cook animals. (d) in the same expedition and in roughly the same layer of excavation, scientists found rudimentary wood cutting and hunting tools used by early humans.