A50-ml crude extract of skeletal muscle contains 32 mg of protein per ml. ten μl of the extract catalyzes a reaction at a rate of 0.14 μmol product formed per minute. the extract was fractionated by ammonium sulfate precipitation, and the fraction precipitating between 20% and 40% saturation was redissolved in10 ml. this solution contains 50 mg/ml protein. ten μl of this purifi ed fraction catalyzes the reaction at a rate of 0.65 μmol/min. (a) what is the degree of purifi cation (fold purifi cation)? (b) what is the percent yield of the enzyme recovered in the purifi ed fraction?

The many volcanoes located along the edge of the pacific ocean make up the ring of fire. how does subduction play a role in the volcanic activity in the ring of fire?

Theories basic to all of the life sciences include the germ theory of disease. theory of evolution by natural selection. o two of these answers are correct none of these answers are correct o cell theory.

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.