biolgy chapter 2

in a well designed experiment, ___ independent variables change

1

which of the following is an accurate description of a testable question?

a question that can be answered using an experiment

which of the following is an accurate description of a testable question?

a question that can be answered using test or experiments

which of the following problems could be solved following the steps of the scientific method?

all of the above

ming is having trouble sleeping and decides to participate in a study to determine whether a certain medication helps people sleep. there are 30 volunteers each of whom is assigned to 1 of 2 groups. volunteers in group 1 are given the medication and volunteers in group 2 are given a placebo (pill w no meds). which step is important in order to ensure scientifically valid results?

assigning the subjects to group at random

which of the following should be included when making a general question table ?

both the cause and effect of the change that is being tested

which of the following should be included when making a general question testable?

both the cause and effect of the change that is being tested

several students in a biology lab tested mealworms preference for damp or dry conditions. the students placed 50 mealworms one by one in the middle of a layer of paper towels with a damp area and a dry area. the mealworms were allowed to move freely over the paper towel for 10 min. after 10 minuites the students noted the location of each mealworm.... which of the following would provide the most accurate results for an experiment?

compare a large sample size from multiple trials

the part of the experiment that is established to dtermine what happens under normal conitions

control

in an experiment, one group that is tested does not experience any change in variables that are being studied. what is that group called

control group

which of the following is an example of a dependent variable?

counting the number of seeds that sprout in 10 different containers that recieved different types of fertilizer

the part of the experiment that is measured to determine the effects of the experiment

dependent variable

which of the following is an example of a testable question?

does increasing the tempature of water cause salt to dissolve at a faster rate?

which of the following is an example of a testable question?

does increasing the tempature of water cause salt to dissolve faster?

a testable question states a general observation of nature

false

all questions in science are testable

false

all questions in science are testable.

false

does adding fertilizer have an affect on the growth rate of a plant? what is the dependent variable in this question?

growth rate

a scientist wanted to learn more about population growth in baceteria. the scientist wanted to know "does storing bacterial cultures at a lower tempature affect the growth rate of the bacterial populations?" in this scenario what is the dependent variable?"

growth rate of the population

which of the following questions would basic research be used to answer?

how do dragon flies reproduce?

the part of the experiment that the scientist changes in order to test the effects

independent variable

what is a hypothesis?

it is a statemnt of what the researcher thinks will happen in an experiment

the independent variable is the variable ___

manipulated by the scientist running the experiment

several students in a biology lab tested mealworms preference for damp or dry conditions. the students placed 50 mealworms one by one in the middle of a layer of paper towels with a damp area and a dry area. the mealworms were allowed to move freely over the paper towel for 10 min. after 10 minuites the students noted the location of each mealworm.... which conclusion best supports the data collected in both experiments?

mealworms are more strongly influenced by food than damp or dry coditions

why should you preform multiple trials of experiments ?

multiple trials provide more results in order to eliminate inconsistencies due to human error

if a researcher makes an experimental observation that is contrary to well established scientific understanding, what should the next step be?

re-evaluating the procedure and replicating the experiment

the part of the experiment that is analyzed in order to form a conclusion.

results

which of the following describes a controlled experiment

set up 10 plants with the same seeds, sunlight and water and vary the types of fertilizer

what is the first step of the scientific method?

state the problem

which experimental design would provide scientist with the best data for investing which type of feed yields the greatest gain in lean muscle mass in cattle?

test 5 similar groups of cows with 5 different feed mixtures and measure their weight gain at the end of a 6 week trial

applied science involves research____

that is necessitated by the problems resulting from some current issue

does adding fertilizer have an affect on the growth rate of a plant? in this question, what is the independent variable?

the fertilizer

which should be included in a testable question?

the indepentent and dependent variables

a scientist wanted to learn more about population growth in baceteria. the scientist wanted to know "does storing bacterial cultures at a lower tempature affect the growth rate of the bacterial populations?" in this scenario what is the independent variable?"

the tempature

variables in an experiment are...

things that can affect the outcome

what is the purpose of performing a controlled experiment?

to provide consistent results that can be repeated

it is important to run an experiment many, many times to get valid results

true

dr. hansen performs an experiment testing the effectivness of different cough syrups. identify the indepentent variable in the experiment

type of cough syrup

which of the following is an example of an independent variable ?

using different brands of fertilizers on 10 different containers of plants

___ are things that can affect the outcome of an experiment

variables

why do plants grow is a general question? which of the following demonstrates a testable question for plant growth??

will adding fertilizer to a plant increase the plant height after 3 weeks?

why do plants grow? is a general question. Which of the following demonstrates a testable question for plant growth?

will adding fertilizer to a plant increase the plant height after 3 weeks?