In eukaryotic cells, dna is packaged with proteins into structures called chromosomes. what advantage do chromosomes provide the cell?

a.
they allow all genes to be expressed at the same time.

b.
they allow random distribution of genetic material when a cell divides.

c.
they ensure equal division of genetic material when a cell divides.

d.
they eliminate the need for a nuclear membrane.

Briefly describe the scenario that was discussed in the behaving brain that demonstrated that the brain can change based on state or mood. which disease could the research involving rats and learning experiments that was discussed in the behaving brain ultimately with? in the behaving brain, what is a common misunderstanding about amnesia that was mentioned? what is the truth about amnesia that's mentioned? what does research discussed in the responsive brain show to be different in men and women's reaction to touch? what was discussed in the responsive brain as being brain-based and a vital part of normal growth and development in young children? in the responsive brain, what do they discuss as a possibility for leading to deficiencies in cognitive impairment as we age? in the responsive brain, what did the research involving african cichlid fish demonstrate? briefly describe the back story and affliction of the author of peter pan. what did you find most interesting about the behaving brain video, and why? what did you find most interesting about the responsive brain video, and w

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

Astudent analyzed ears of corn that demonstrated two traits in the f2 kernels, purple or white colors and smooth on wrinkled shapes. a tabulation of 135 individual kernels gave the following results: purple and smooth = 75 white and smooth = 28 purple and wrinkled = 24 white and wrinkled = 8 what would be the only phenotype present in the f1 ger