Ineed mrs. johnson's science class perform an experiment. they combine two substances that react with lots of fizzing and bubbling. the class determines the mass of the substances before and after the experiment and find that the substances have less mass after the experiment. hannah wants to know why the experiment didn't obey the law of conservation of mass, but chris says it did. who is right and why? question 8 options: hannah is right because the class may have made an error in determining the mass of the substances. chris is right because some of the mass of the reactants escaped as gas. chris is correct because the reactants and products do not have to have the same mass, but they do have to weigh the same. hannah is right because the mass of the reactants was different than the mass of the products.

In sexual reproducing animals once fertilization of the egg takes place, the exists as a single cell until cell division begins. a) egg b) larva c) sperm d) zygote

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.

Actinobacteria sp. are fermenting organisms (which do you use oxygen to breathe) referred to as chemoorganohetereotrophs this means they break down organic material and convert it to inorganic material. which part of the carbon cycle does this describe