Biology Answers

Water is described as Polar Covalent. What does that mean

A student reads in a newspaper that the soil in his area contains high levels of arsenic. Based on this information, he believes that his fellow high school classmates have this metal present in their bodies. To test his hypothesis, he conducts an investigation of the soil in his schoolyard to see if it is contaminated with arsenic. He tests seven different areas around the school and finds high levels of arsenic in each. He concludes that the students at the school must have high levels of arsenic in their systems as well. Which of these is the best evaluation of his conclusion?

A.
His conclusion is valid because he tested enough areas of soil to validate his hypothesis.

B.
His conclusion is flawed because he did not test the soil at the homes where the students lived.

C.
His conclusion is valid because arsenic is a toxic metal and is easily absorbed by the human body.

D.
His conclusion is flawed because he did not test the students to see if their bodies contained metal arsenic.

Describe three hypotheses proposed to account for the decline in cell numbers during the death phase of a growth curve.

fermentation is carried out in an open fermenter, with nutrients added and product removed at a steady rate throughout

Discuss the potential uses of artificial cells and/or cell like materials and whether you consider them to be a good substitute for the natural versions.

An ecologist wanted to determine the level of acidity that salmon eggs could tolerate they placed eggs in different acidity levels and counted the number of fish that hatched successfully