Scientific Investigation and Validity Quiz

During an experiment, readings for blood pressure in a person's body were found to be constant. However, when measured by a different blood pressure cuff, the readings differed by 15 points for each reading. This difference indicates that the results are ______ but not ______.

• independent, reliable

• reliable, valid

• dependent, reliable

• valid, independent

Which question cannot be tested with a scientific investigation?

• Do people who drink tea have a higher risk of brain illnesses than non-tea drinkers?

• Do people who drink tea stay more alert than non-tea drinkers?

• Are people who drink tea happier than people who don't drink tea?

• Are people who drink tea more likely to exercise than non-tea drinkers?

Jordan's grandmother uses the juice from squeezed lemons to remove stains from his shirt. He hypothesizes that the juice is the only part of the lemon that is effective at removing the stains, because it's an acid. Which two steps would help Jordan determine whether his hypothesis is scientifically supported?

• He should test the acidity of different parts of the lemon, including the juice, pulp, and skin.

• He should conduct an opinion poll of residents to see if they agree with his hypothesis.

• He should make identical stains on T-shirts and see whether different parts of the lemon will remove the stain.

• He should find literature on housekeeping websites that support the use of lemon juice at removing stains.

• He should compare lemon juice with other acidic juices to see if they all remove stains.

Sarah performs an experiment to determine the effect of nitrogen on plants. She studies the effect of nitrogen on the growth of the root hair, height of the plants, and nodule formation. Which factor is an independent variable?

• amount of nitrogen

• growth of root hair

• nodule formation

• height of the plants

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NGSS.MS-LS1-5

NGSS.MS-LS2-1

Which two hypotheses can be supported with quantitative data?

• People who eat low-protein diets are more likely to have less muscle mass.

• It’s ethical to eat a vegetarian diet.

• People are happier during the summer than during the winter.

• Eating an organic diet makes people feel better.

• Eating less salt lowers blood pressure over time.

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NGSS.HS-LS4-3

An element has an atomic mass number of 16 and an atomic number of 7. The element has [7, 8, 9] protons and [7, 8, 9] neutrons.

• 8 protons, 9 neutrons

• 7 protons, 8 neutrons

• 9 protons, 7 neutrons

• 8 protons, 8 neutrons

• 7 protons, 9 neutrons

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NGSS.MS-PS1-1

Select the correct answer. Dorothy works as a medicinal chemist in a pharmaceutical company. What could one of her assignments be?

• to test new X-ray equipment

• to develop new surgical techniques

• to design new software that helps in the research of new molecules

• to research molecules in spider venom for new pain medication

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NGSS.HS-LS1-6

Select the correct answer. The periodic table houses noble gas elements in group 18. These elements are highly stable and rarely react with any other elements. What is one possible reason for the stability of the noble gas elements?

• They easily form covalent bonds.

• The compounds that they form with other elements are very unstable.

• Their outermost shell has the maximum number of electrons that it can hold.

• They require less activation energy.

Select the correct answer. Which of these elements is rarely found in organic molecules?

• hydrogen

• oxygen

• barium

• carbon

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NGSS.MS-PS1-1

Select the correct answer. What was Anton van Leeuwenhoek's contribution in the development of cell theory?

• He built the first compound microscope.

• He was the first to observe live cells in a sample of pond water.

• He concluded that cells exist in liquids.

• He stated that all living things are made of cells.

Tags

NGSS.MS-LS1-1