BIO 2H - Valid Conclusions

Which is the MOST valid conclusion based on this graph?

• Enzymes are not affected greatly by temperature.

• Enzymes work most effectively at low temperatures.

• Raising the temperature always makes an enzyme work better.

• Enzyme function decreases after a certain favorable temperature.

Ten frogs were placed in a large container with three sections. Each section had equal amounts of light, shelter, food, and water. Each section was painted a different color: red, green, or blue. Daily observations were made of the frogs’ locations for six weeks. These data were compiled to produce the following frog location frequencies.

• Six frogs out of ten preferred the blue area.

• The frogs randomly moved into the colored areas.

• Only two frogs entered the red area.

• Frogs tended to move to the green area most often.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Ten samples of a new culture media were each inoculated with a different strain of bacteria and incubated at the same temperature. Nine of the cultures grew.

Which of these conclusions can be drawn from this information?

• The culture media used in the experiment was not capable of sustaining bacterial growth.

• The temperature varied greatly during the experiment.

• Only the culture that failed to grow bacteria was inoculated properly.

• One of the bacteria samples needed nutrients not present in the new culture media.

Students compared the germination rates of seeds that had been exposed to radiation with that of normal non-irradiated seeds. Their results are shown in the graph above. Which of the following should the students conclude from this graph?

• Irradiation has no effect on germination rate.

• Irradiated seeds germinate more quickly than non-irradiated seeds.

• Irradiated seeds germinate at a slower rate than non-irradiated seeds.

• If given enough time, all seeds will germinate even if they have been irradiated.

Tags

NGSS.MS-LS1-5

Students in a biology class used black construction paper to cover both sides of a geranium leaf on a living plant. They covered another geranium leaf on the plant with red cellophane and a third geranium leaf on the plant with green cellophane. They put the geranium plant in bright sunlight and left it for two days. They then removed the experimental leaves and extracted the chlorophyll from them. They tested each leaf for the presence of starch by covering it with iodine. The chart below shows their results.

Based on the data in the table, which of the following is the best conclusion?

• Geraniums absorb green light better than red light.

• Green plants produce starch in the presence of any color of light.

• Iodine turns red in the presence of starch produced by photosynthesis.

• Geraniums carry out photosynthesis in the presence of white or red light.

Tags

NGSS.MS-LS1-5

NGSS.MS-LS1-6

Students in a biology class used a procedure called paper chromatography to separate the pigments in a green leaf. They added drops of extracted leaf juice to the bottom of a strip of filter paper and suspended the paper in a test tube with a small amount of solvent in the bottom. In this type of experiment, leaf pigments separate as they move up the paper, carried by the solvent. The procedure is summarized in the following drawings.

From these results, the students should conclude that the –

• leaves in this experiment contain four different pigments

• pigments in some leaves are not chlorophyll

• leaf juice did not dissolve in the solvent

• leaf pigments traveled at the same speed up the paper

Students in a biology class measured the rate of metabolism of sugar by yeast. They compared the rates of metabolism with three different kinds of sugars by counting the number of bubbles produced per minute. Based on their data, the students' best conclusion would be that the rate of metabolism of yeast is –

• the same for all types of sugars

• independent of the food source

• lowest when galactose is the food source

• identical for the food sources sucrose and fructose

Tags

NGSS.MS-LS2-1

Plant cells were put into sucrose solutions, each of which had a different concentration. Scientists then measured the rate at which the plant cells absorbed the sucrose at each of the concentrations. Their results are shown in the above graph. Which is the best conclusion that the scientists could draw based on their data?

• The rate of absorption of sucrose does not continue to increase with all concentrations of sucrose.

• The rate of absorption of sucrose by plant cells is not affected by the concentration of sucrose.

• As the concentration of sucrose decreases, the rate at which plant cells absorb sucrose always increases.

• As the concentration of sucrose increases, the rate at which plant cells absorb sucrose always increases.

Scientists wanted to determine the best temperatures for growing fish in a hatchery. They measured the growth of two kinds of fish and calculated the percentage of fish that reached maximum size at various temperatures. The results of their experiment are shown in the above graph. Which conclusion are the scientists most likely to reach?

• Under no conditions will brook trout reach their maximum size.

• Carp and brook trout should be grown under the same conditions.

• A water temperature of 15 oC is best for carp, and 27 oC is best for brook trout.

• At the optimal temperature for carp, no brook trout would reach its maximum size.

Tags

NGSS.MS-LS1-5

Students in a biology class recorded the number of stomata on the top and bottom sides of different plant leaves. The table below shows some of the data collected by one team of students.

The students plan to graph their data. Which of the following would be most appropriate to show the results of their experiment?

• circle graph

• double bar graph

• flow chart

• line graph