Lab 8

Question 1

A common feature to all scientific experiments is the employment of experimental . . .

Answer 1

controls

Question 2

In a controlled experiemnt, all of the variables are kept the same in order to be consistent. There is only one variable that is changed for these kinds of studies, and it is known as the . . . variable

Answer 2

independent variable

Question 3

In experimental design, researchers often (but not always) will include 2 types of controls. These are known as the . . . . and . . . controls, which show constiutive affirmative and negating result respectively.

Answer 3

positive/negative

Question 4

A researcher is studying the effects of different bacterial nutrient solutions on the growth rate of E coli. The researcher knows that for a culture of E coli to grow well, it requires warmer than room temperature heat, semi-aqueous media, and nutrient solutions. If the researcher is primarily interested in the effects of different nutrients on bacterial growth rates, what variables will they want to keep consistent across all study E coli cultures?

Answer 4

The temperature and media the cultures are grown in, and the amount of time the cultures are allowed to grow

Question 5

True or False: A hypothesis is often stated in such a way as to assess the cause and efect relationship between the alteration of a variable of interst and an associated observable phenomenon (namely, stating a hypothesis in a manner such as “if . . . . is done, then we would expect . . . to result”)

Answer 5

True

Question 6

What are two major poducts of yeast fermentatin?

Answer 6

Ethanol and CO2

Question 7

What is a positve control?

Answer 7

A group in an experiement that receives a treatment with a known result, and therefore should show a particular change during the experiment

Question 8

What is a negative control?

Answer 8

A group in an experiment that does not receive any type of treatment and, therefore, should not show any change during the experiement

Question 9

Steps of Scientific Method (6)

Answer 9

1) Observation; 2) Research; 3) Hypothesis; 4) Experiment; 5) Conclusion; 6) Share results

Question 10

Observation

Answer 10

All that can be observed with the five senses (smell, sight, taste touch, hearing)

Question 11

Research method

Answer 11

Use reliable sources to learn background information

Question 12

Hypothesis

Answer 12

Prediction of what you believe will occure (if, then, and be specific)

Question 13

Types of experiental data collected (2)

Answer 13

1) Qualitative; 2) quantitative

Question 14

Qualitative data

Answer 14

Relies on descriptions

Question 15

Quantitative data

Answer 15

Relies on numbers

Question 16

Types of variables used in experiment (2)

Answer 16

1) Independent; 2) dependent

Question 17

Independent varable

Answer 17

The thing you change

Question 18

Dependent variable

Answer 18

The thing you measure

Question 19

Experimental group

Answer 19

The group where the independent variable is altered

Question 20

Control group

Answer 20

Other “normal” or unaltered group used to compare against experimental group

Question 21

Types of groups used in an experiemnt (2)

Answer 21

1) Experimental group; 2) control group