In breeding pure-breeding large and small strains of mice, you cross individuals of each strain and note that their offspring are intermediate in size. two models (explanations) to account for this result are (1) that body size in these strains is due to one gene with alleles that show incomplete dominance and (2) that body size is a polygenic trait. how could you distinguish between these models? '

backcrossing

Explanation:

when you cross the offspring (inttermediate size) to one of the parental strains, (the small strain for example)  you should get 1/2 intermediate size and 1/2 parental size (small) if body size is due to  single gene. On the other hand if the trait "size" is polygenic you should get mice around half way between small and intermediate sizes.  

answer:

the water molecules are transferred from the roots to the stem or top parts of the tall tree because of important properties of water which are adhesion, cohesion and capillary action. cohesion is the property of water molecules keeps water molecules in a combined state by sharing of bonds between them at the atomic level. adhesion allows the interaction of water molecules with other substances or substrate. adhesion will cause the attachment of water molecules to the wall of the vessel (xylem) of the plant. capillary action occurs when the adhesive force to the vessel wall is stronger than the cohesive force between water molecules. capillary action mimics the transfer of water from a tube or pipe. in this way water utilizes its property to transfer water from down to top level of the plant.  

the answer is lactic acid from anaerobic respiration. the acid in lactic acid is what creates sore and burning muscles. if you think about how acid burns that will give you a clue for questions like this.