Which determines the reactivity of an alkali metal? A) its boiling and melting points
B) the shininess of its surface
C) the number of protons it has
D) its ability to lose electrons

Study this image. which statements best describe the rock shown? check all that apply. the grains of this rock are jagged. this rock has several coarse grains. the grains in this rock are very large. this rock has a non-banded pattern. the color of this rock is determined by its texture.

Which of the following is true of microbes? a. ninety-nine percent of all microbes are pathogenic.b. gene expression in bacteria is very similar to gene expression in humans, which facilitates the use of bacteria in recombinant biotechnology and gene therapy.c. all bacterial enzymes are harmful to humans and the environment.d. microbes create pollutants and toxins that harm the environment.

Genetic disorders can result when sister chromatids fail to seperate properly. during what phase is this problem most likely to occur?