You fill a shallow pan with water and place a drop of red ink in one end of the pan and a drop of green ink in the other end. Which of the following is true at equilibrium? a. The red ink is uniformly distributed in one-half of the pan, and the green ink is uniformly distributed in the other half of the pan. b. The red and green inks are uniformly distributed throughout the pan. c. Each ink is moving down its concentration gradient. d. The concentration of each ink is higher at one end of the pan than at the other end.

The first three phases of the cell cycle are collectively known as (1 point) play audio cellular respiration. telophase. mitosis. interphase.

Experiments in environmental toxicology can sometimes be manipulative experiments in which the researcher actively chooses and manipulates the independent variable. in hunt's study, for example, dosages of bpa were manipulated and the effects were measured. in manipulative studies, the researcher controls all the other variables in the experiment, so any health effects observed in the test subjects can be attributed to differences in the independent variable. in other cases, researchers use natural experiments in which the dependent variable (typically a measure of organism health) is measured under differing contexts that are not manipulated. say, for example, that an accidental chemical spill contaminates five ponds. to determine the possible effects of the toxic chemical on frogs, a researcher could compare the hatching rate of frog eggs laid in those five ponds to the hatching rate of eggs laid in five uncontaminated ponds nearby. this would be an example of a natural experiment because concentrations of the toxic chemical in the ponds were not controlled by the experimenter, but rather resulted from the chemical spill. drag type of experiment on the left to the example of experiment on the right. blood concentrations of bpa in college students are compared to their recent manipulative consumption of canned food items 2. the feeding behavior of fish in streams that receive acidic runoff from strip mines is compared to the feeding behavior of fish in unaffected streams. the deformity rate in baby birds from nests in pesticide-sprayed fields is compared to the deformity rate in birds from nests in unsprayed fields 4 tumor development is compared in mice exposed to five dosages of a known carcinogen in the laboratory foraging activity levels are compared in tadpoles exposed to four concentrations of toxic metals in the laboratory. growth of corn plants is compared in field plots sprayed with three different dosage: s of weed killer 7 bpa concentrations in the urine of people with diabetes are compared to bpa concentrations in the urine of people without diabetes - natural; manipulative

The galapagos island contain 13 species of finches four of the species are seen here it is believed that all of the species had one common ancestor and overtime