Judy used the following soil triangle to identify a sample of soil as silty clay. Soil texture triangle. Clay soil is approximately 45 percent or less sand, 50 percent or more clay, and 40 percent or less silt. Silty loam soil is approximately 50 percent or less sand, 30 percent or less clay, and 50 percent or more silt. Sandy clay soil is approximately 45 to 65 percent sand, 35 to 55 percent clay, and 25 percent or less silt. Sandy clay loam soil is approximately 45 to 80 percent sand, 20 to 35 percent clay, and 35 percent or less silt.

Which description of soil likely allowed Judy to make this identification? (2 points)

a
Mostly large particles, with a gritty texture, 75% clay, 15% sand, and 10% silt

b
Mostly large particles, with a sticky texture, 65% clay, 10% sand, and 25% silt

c
Mostly small particles, with a sticky texture, 50% clay and 5% sand, and 45% silt

d
Mostly small particles, with a smooth texture, 30% clay, and 25% sand, 45% silt

Listed in the item bank are some key terms and expressions associated with the categories seen in the venn diagram. to find out more information about items, some have more details available when you click on them. drag and drop each item onto the proper area of the diagram. if an item describes more than one category, be sure to place it in the overlapping space. viruses are tiny infectious pathogens that cause many different diseases, such as polio, and the flu. though they are similar to one celled organisms in some ways, in many ways they are very different. use the venn diagram below to show the similarities and differences between viruses and living organisms.

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 vaccine in a flu shot contains weakened flu viruses. how does a flu shot work with the immune system? a. it destroys lymphocytes. b. it destroys macrophages. c. it activates macrophages. d. it activates lymphocytes.