Scientific Method and Graphing Review

Base your answers to questions 1 through 3 on the information below and on your knowledge of biology. An experiment was carried out to answer the question "Does the pH of water affect the growth of radish plants?" Two groups of ten radish plants were set up. One group was watered with water having a pH of 3.0, and the other group was watered with water having a pH of 7.0. Both groups of plants received the same amount and intensity of light, the same amount of water, and they were grown in the same type of soil. The heights of the radish plants were measured every 2 days for a period of 2 weeks. 1. Which activity might help to increase the validity of this experiment?

• repeating the experiment several times

• using two different types of radish seeds in each group

• using the same pH for both groups of plants

• placing one set of plants in sunlight and one in darkness

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

An experiment was carried out to answer the question "Does the pH of water affect the growth of radish plants?" Two groups of ten radish plants were set up. One group was watered with water having a pH of 3.0, and the other group was watered with water having a pH of 7.0. Both groups of plants received the same amount and intensity of light, the same amount of water, and they were grown in the same type of soil. The heights of the radish plants were measured every 2 days for a period of 2 weeks. What is the dependent variable in this experiment?

• heights of the plants

• pH of the water

• temperature of the water

• type of soil

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

An experiment was carried out to answer the question "Does the pH of water affect the growth of radish plants?" Two groups of ten radish plants were set up. One group was watered with water having a pH of 3.0, and the other group was watered with water having a pH of 7.0. Both groups of plants received the same amount and intensity of light, the same amount of water, and they were grown in the same type of soil. The heights of the radish plants were measured every 2 days for a period of 2 weeks. Which of the following is a hypothesis for this experiment?

• Does the pH of water affect the growth of radish plants?

• Will the amount of water alter the heights of the radish plants?

• The temperature of the water will affect the heights of the radish plants.

• The pH of the water will affect the heights of the radish plants.

Tags

NGSS.MS-LS1-5

A student conducted an experiment to determine if listening to different types of music would affect pulse rate. She thought that pulse rate would change with different types of music. Each person participating in her experiment listened to seven different selections of music for 30 seconds each. The pulse rates were taken after each 30-second interval of music. Based on her experiment, the student concluded that a person's pulse rate changed when listening to different types of music. The component missing from this experiment is a

• prediction

• hypothesis

• control group

• research plan

Which statement describes the best procedure to determine if a vaccine for a disease in a certain bird species is effective?

• A) Vaccinate 100 birds and expose all 100 to the disease.

• B) Vaccinate 100 birds and expose only 50 of them to the disease.

• C) Vaccinate 50 birds, do not vaccinate 50 other birds, and expose all 100 to the disease.

• D) Vaccinate 50 birds, do not vaccinate 50 other birds, and expose only the vaccinated birds to the disease.

Tags

NGSS.HS-ETS1-3

An investigation was designed to determine the effect of ultraviolet light on mold spore growth. Two groups of mold spores were grown under identical conditions, except one group was exposed only to ultraviolet light, while the other group was grown in total darkness. In this investigation, the group of mold spores grown without receiving any ultraviolet light is known as the

• control

• hypothesis

• dependent variable

• limiting factor

Which measurement would most likely be taken to determine the effect of different mineral salts upon the experimental groups?

• weight of the medium in each pot

• temperature of the 40 pots

• height of the 40 plants

• distance of each plant from the light source

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

What was added to the control group of pots?

• water, only

• nitrogen salts, only

• potassium salts, only

• potassium and phosphorus salts

Tags

NGSS.MS-LS1-5

In an experiment, what should be the relationship between the control group and the experimental group?

• They should be different in size

• They should resemble each other in at least two respects

• They should not be similar in any respect

• They should be identical in all respects except one

In a scientific investigation, after the question is defined, the next step is most likely

• formulating a hypothesis

• identifying needed equipment

• designing the experiment

• collecting the data