Most organisms have a fight-or-flight response when they sense danger. In mammals, two organ systems work together to produce this response. Which of these body systems is involved in the information above?
Select one:

respiratory and circulatory

nervous and digestive

respiratory and excretory

nervous and endocrine

If an organ has six haploid chromosomes,how many chromosomes are present. 6 12

Ras is a g-protein that is activated when a growth factor attaches to egfr. its activation results in the replacement of a gdp molecule with a gtp molecule, thus allowing a signal transduction pathway to be activated. considering the signal pathway illustrated on this page, what is one potential outcome of a mutation in the ras gene that leads to ras protein hyperactivity. be specific.

Lactase is essential for digesting lactose in milk. this enzyme is specific for this sugar. why? molecules and active sites vary in size; only properly sized molecules can fit.there is a precise compatibility between the active site and the lactose molecule.specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.