WORD BANK -S -new -thymine (T) -hydrogen -original
-replication -helicase -identical -nucleotides -cytosine (C)

The process of making a copy of DNA is called DNA and it occurs during phase of interphase. Before replication can begin, the double helix must unwind. After being unwound, the DNA strands are separated by the enzyme . Helicase separates the DNA molecule by breaking the bonds between the nitrogen bases. With the DNA strands separated, DNA polymerase can come in and add complementary (matching) to the separated strands of DNA. When DNA polymerase passes over an adenine (A), it will attach a. DNA polymerase will also match with guanine (G). DNA polymerase will also proofread the new strands of DNA to check for mis-paired nitrogen bases. The process of DNA replication produces two strands of DNA. The new DNA molecules are made of one strand of DNA and one strand of DNA. The new DNA molecules will wind up to return to their double helix shape and prepare for cell division.

Match each description to the appropriate biome. tropical savanna desert tropical rain forest taiga tundra has sparse vegetation and very cold temperatures located near the equator and contains trees that form dense canopy layers is very hot and dry, and has plants that need little water has cold winters, heavy snowfall and is dominated by conifers has warm temperatures and is dominated by grasses

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

Im inn a ! what"s the answer which of the following is one way creativity can scientists? by ensuring they follow the scientific method by increasing the amount of time it takes to complete scientific experiments by making sure they only try things that have already been proven by leading them to ask more questions about the natural world