Experimental Design advanced

Mr. Bullock is helping Mrs. Julius with a lab. He makes three mixtures of milk and peanut butter. He puts lids on each container and freezes each mixture. Some of his measurements are listed above.

Choose all the statements that describe the patterns in the mixtures.

There are multiple answers to select!

(Choose 3)

• The weights of the mixtures do not change in the freezer.

• Mr. Bullock added the same amount of milk to each container.

• The total weight is the sum of all ingredients for each mixture.

• Mr. Bullock added the same amount of peanut butter to each container.

Tags

NGSS.MS-PS1-2

•Let’s take a look at the data generated from an experiment where blue and green lights were used to grow tomato plants. Which of the following would make the data from this experiment more reliable?

• Grow the plants for more than 20 days

• Use white light as a control group for comparison

• Use more colors of light to see how the effects of each color compares

• Use different types of plants to see the effect different colors of light has on different plant species

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

During an experiment, a student measures the mass of ice and of liquid water and then places the mixture into a freezer for a day. The table shows the data.

What will the student have at the end of the experiment?

(Read the chart carefully)

• 85 grams of ice

• 185 grams of ice

• 125 grams of liquid water

• 150 grams of liquid water

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

If you were creating a graph for this data set, what would be the best scale for this data?

Days Cm

1- 16.5

2- 14.5

3- 22.7

4- 26.0

5- 32.5

• count by fives to 35

• count by three's to 30

• count by ones to 31

• count by twos to 34

Tags

NGSS.MS-PS3-1

Dr. Peterson does an experiment to research the growth rate of mice. He has two groups of mice. He feeds one group a type of food and adds chemical A, which is supposed to increase the growth rate. The other group he feeds the same food without chemical A added. His research shows that chemical A decreases the growth rate by 30%. He does the experiment 4 times and comes up with the same result each time.

Dr. Peterson concludes that chemical A does increase the growth rate of mice. Is Dr. Peterson's conclusion supported by scientific knowledge?

• Yes; any study that involves a percentage is based on scientific knowledge.

• Yes; his conclusion is supported by evidence from his experiment.

• No; science cannot be used to research small animals such as mice.

• No; his conclusion is not supported by the evidence from the experiment because the growth rate decreased.

Tags

NGSS.MS-LS1-5

Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, Smithers counts how many stacks of papers each group has made. GroupA made 1,587 stacks, Group B made 2,113 stacks

• Independent Variable

• Group B

• Control Group

• (Productivity)

  # of Stapled stacks of paper

• Dependent variable

• The task of stapling papers

• Constant

• Group A

• Experimental Group

• Special Juice

An experiment was carried out to determine whether drinking caffeinated soda increases pulse rate. The pulse rates of two groups of people at rest were measured. Group A was then given caffeinated soda and group B was given caffeine-free soda. One hour after drinking the soda, the pulse rates were measured. The participants in the experiment were all the same age, and they were all given the same amount of soda.

• Experimental group

• pulse rate of each group before caffeine

• Dependent Variable

• Caffeinated soda

• Control Group

• Pulse rate

• Independent Variable

• Pulse rate of each group after caffeine

• Constant Variable

• Amount of soda given to the groups

An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil, sunlight, and listens to the same music.

• Dependent Variable

• Type of liquid

• Constant variable

• Group of plants given different types of liquids

• Control group

• Plant growth

• Experimental Group

• Amount of Soil

• Independent Variable

• Group of plants given water

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

Ben makes five paper helicopters with different wing lengths using the same type of paper. He drops them the same way from a height of two meters for five trials each. He records the amount of time it takes for each helicopter to fall to the ground.

• Dependent

• Amount of time it takes the helicopter to hit the floor

• Independent Variable

• Type of paper

• Constant

• Wing Length

Tags

NGSS.MS-PS2-2

A student experimented to test how different antibiotics affect the growth of bacteria. She treated one paper disk with water, and three others with different antibiotics. Each was placed on a dish of the same size and given the same nutrients to feed the bacteria so they will grow.

• Constant Variable

• Group of disks with antibiotics

• Independent Variable

• The type of antibiotic

• Experimental Group

• Group of disks with water

• Control Group

• The amount of bacterial growth

• Dependent

• Nutrients given to the bacteria

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1