Unit Test Answers

What would most likely be included in the “Analysis” section of a lab report?

The scatterplots indicate the population of rabbits in the population over time. The y-axis represents the number of rabbits and the x-axis is time. Which graph most likely represents a rabbit population that found a new, larger habitat, but then eventually experienced an increase in predation?

A student conducted an experiment to test whether talking to plants would help them to grow faster. He set up the following two groups:Group 1: spoken to and hand watered Group 2: not spoken to and watered with sprinklers After three weeks, the plants in Group 1 showed much more growth than those in Group 2. Based on the results of this experiment, which is the best conclusion?

Take a look at the statement below:Fish meal is better than artificial fertilizers.How could this statement be revised to make it a hypothesis?

The graph shows a student’s data from an investigation about plant growth in five plants of the same type.WeekAvg. Plant Height (cm)Avg. Growth (cm)02NA1312633934145Which is the best way to display this data for analysis?

All theories are hypotheses, but not all hypotheses are theories. Francis wants to know if a specific hypothesis he is researching is a theory. Which describes how Francis would know the hypothesis is a theory?

A biology class is studying the effect of temperature on the amount of growth of duckweed in an aquarium. What type of data will the class need to collect, and which tools will most likely be used?

Alli and her classmates want to know which species of oak produces the acorns that squirrels prefer. Which possible procedure is likely to produce the most reliable results?

Most scientists agree that saturated fats contribute to high levels of “bad” cholesterol in a person's blood, while monounsaturated fats and polyunsaturated fats lower this type of cholesterol in a person's blood. The table below shows data about fats in some common foods.Food (14 g)Saturated fat (g)Monounsaturated fat (g)Polyunsaturated fat (g)Canola oil1.08.93.9Margarine1.65.43.4Olive oil1.99.91.4Lard5.05.81.4Butter7.93.70.5Joyce and Linda are identical twins who are 50 years old and enjoy exercising daily. Joyce avoids eating any dairy or animal products and eats granola made with canola oil for breakfast. Linda prefers rich foods, and eats bacon, eggs, and buttered toast each morning. Which statement describes a logical inference that can be made from the provided information?

Clara wrote the following hypothesis for an experiment about acidophilic bacteria.Bacteria cells will stop dividing in a basic (alkaline) environment because of the high pH.Which statement is the best way to restate the hypothesis so that it is more specific?

In double-blind studies neither the test subject or the researcher knows who was given the drug and who was given the control. Why are these studies effective for testing a drug that may elevate mood and relieve feelings of depression?

Hybrid seeds are deliberately crossbred for particular traits, such as growth pattern or disease resistance. They have been hand-pollinated and are patented, often sterile, and genetically identical within food types. These plants are usually grown in a monocultural environment and are cultivated for mass production and sale. They must be sturdy to withstand mechanical picking and cross-country shipping. They do not compare to the quality and taste of heirloom plants, but they do produce large, healthy fruit that appeals to most shoppers. Unlike heirloom seeds, if one saves a hybrid seed, one will not get the same plant again. Which statement can be removed and not affect the excerpt’s reliability?

Which equipment is best to hold and to measure liquids?

A recent encyclopedia entry about dogs cites multiple research papers done by scientists at veterinary schools. According to the article, Labrador retrievers come in two specific breeds: English and American. The English breed is described as stocky and heavy, while the American breed is described as tall and lanky. The article describes current scientific research as showing that males of both breeds usually weigh about 29-41 kg (65-90 lb), and females weigh 25-32 kg (55-70 lb). Coat colors for both breeds come in solid black, yellow, or chocolate. All labs have strong tails and webbed feet, which help them swim. Devon would like to use this information to determine if his new dog is an English or American Labrador retriever. Which best describes the reliability of the information?

Studying the folding patterns of protein molecules can help microbiologists better understand cellular processes as well as some diseases, such as Alzheimer’s, that are caused by proteins that have misfolded. The folding of these complicated molecules can be simulated on computers, but it takes a lot of processor power and time for even expensive supercomputers to do this. A group of researchers at Stanford University developed software that can be used to distribute the processing of data to anyone who is willing to donate time on their idle personal computers. As a result, the researchers have been able to achieve protein-folding simulations that are far better than those other computing methods have done. Which statement best describes the work of these researchers?

Which statement best explains why the development of a new area of science can lead to changes in a theory?

A scientist wants to prove that certain chemicals in cosmetics are likely to cause harm to developing fetuses, when used by a pregnant woman. What is the most likely limitation she will face in her scientific design?

Why have improvements in microscopes over time resulted in revisions in the cell theory?

Jake and Aisha conducted an experiment together to test the effects of fertilizer runoff on the amount of dissolved oxygen in a lake. They each created a graph from the results. Graph 1: Jake’s Graph Graph 2: Aisha’s GraphJake concluded that the runoff had little effect on the dissolved oxygen levels, and Aisha concluded that the runoff had a major effect on dissolved oxygen levels. What is the most likely reason that Jake and Aisha formed different conclusions?

Asher notices mold on all twenty pea plants in his garden. He wonders what factors are contributing to the mold growth. He hypothesizes that he is giving the plants too much water, which is causing the mold to grow.Asher carries out an investigation in which he waters ten of the plants the same amount as before and gives the other ten plants half as much water per day. Each week, he photographs and records the number of leaves that contain mold. After a month, he observes his data and concludes that there has been little to no change in mold growth. What change to this experiment would be most effective in helping Asher continue to investigate what is causing mold growth?

In late spring, a student began conducting an investigation about the flower preferences of bees. She counted the number of wildflowers in a small plot and created the following table.Plant SpeciesNumber of PlantsDandelion13Indian paintbrush8Queen Anne’s lace20Thistle29She planned to observe the flowers for the next five days for an hour at the same time each afternoon. Then she would plot the data in a multiple line graph to compare the number of bees that visited each flower. Which statement best describes the data in this investigation?

A student does an experiment for a science fair to study whether temperature affects the timing of a cricket’s chirps. The student keeps a cricket in an enclosed box that is heated to different temperatures each day for twelve days. The student records the cricket’s chirps by using a sound-activated microphone so that the timing of the chirps can be measured. The student records the results of the experiment in the table below.Day123456789101112Temperature (ºC)212223242526272829303132Average time between chirps (sec)2.52.62.22.32.01.81.91.81.41.21.51.1Which generalization can be made from the data in the table?

Density is mass per unit of volume. Which pair of lab instruments would a student use to measure the density of seawater?

The excerpt is from an article that Roberto read for science class called “Using the Scientific Method to Study Tomatoes.” The student performed an experiment to test his hypothesis about sunlight and plant height using two plants. He kept everything the same between two tomato plants except he exposed them to different amounts of sunlight. He also used a third plant as a control group, or a group in which no variables are manipulated to confirm the results.Roberto critiqued the work. Which problem did Roberto most likely identify?

Read the passage below. It summarizes survey information.The Global Youth Tobacco Survey asks youth to fill in the answers to several questions about their tobacco use. In this survey conducted between 2000 and 2007, it was found that in youth ages 13-15, 12 percent of boys and 7 percent of girls reported smoking cigarettes. This information was shared and reported on the American Cancer Society website. The information was then used by several industries in the fields of health care, insurance, and education.What is a reason that these data may be unreliable?