LS 15 PHELAN UCLA EXAM QUESTIONS AND ANSWERS (VERIFIED
LS15 MIDTERM - UCLA Phelan
AND WELL DETAILED ANSWERS) LATEST UPDATE 2025/2026
Study online at https://quizlet.com/_5hvxy8
1. 1. Scientific think-
ing, what is it for?
and be able to
use it
2. scientific think- - empirical (based on observations and experiences not solely logic)
ing - self correcting
- observation
- hypotheses
- predictions
- experiments
- conclusions (modify hypotheses, and continue the process)
3. scientific method - organized
- empirical
- methodical
- structured way of finding information about observable events in nature
- lets us reject hypotheses about how the world works
4. steps of the sci- 1. make observations
entific method 2. formulate hypotheses - is it testable? refutable?
3. make a prediction
4. conduct an experiment - control all variables BUT one, randomized, double
blind
5. analyze results, draw a conclusion (if evidence disproves hypothesis, construct
a new hypothesis)
6. report results
5. is the scientific yes! it doesn't have to be step by step
method flexible?
6. put a hypothesis to the test, the results can decisively determine whether a
hypothesis is correct
, LS15 MIDTERM - UCLA Phelan
Study online at https://quizlet.com/_5hvxy8
what does a "crit-
ical experiment"
do
7. class examples of - does it rain more on weekends?
scientific method - real vs artificial vanilla
- "maze bright" vs "maze dull" rats
8. class example: - find average Monday and Saturday rainfall; rains 22% more on Saturdays
does it rain more - hypothesis: particular matter from car exhaust builds up during the week leading
on weekends? to cloud formation and then rain on the weekends
- experiment: collect data from somewhere with no cars (ocean)
- results: there is equal rainfall on each day in the ocean, PROVING that car exhaust
affects the trend of more rain on weekends
9. class example: - Phelan baked batches of cookies with real vanilla and with artificial vanilla
real vs artificial - asked wife which one tasted better
vanilla in choco- - concluded that there was no difference in taste between the types of vanilla used
late chip cookies
10. class example: - have "maze dull" and "maze bright" mice
is maze running - with each generation, test all mice for maze learning ability and breed only the
genetic in mice? top 20% and bottom 20%
- observe new generations
- conclusion: over time, the extremes got more and more exaggerated
- maze running is not genetic but the allele for fear is in mice; less fear = solve
maze quicker, more fear = solve maze slower
11. how to in- - randomize subjects
crease experi- - control your study
ment's power - use a double-blind design
R.C.D. - rat's cause diseases
, LS15 MIDTERM - UCLA Phelan
Study online at https://quizlet.com/_5hvxy8
12. what is it's a poorer model of the situation of interest
the cost-bene-
fit analysis of
having a more
controlled exper-
iment?
13. 2. How does a - a prediction only offers a guess of what will happen in the future
hypothesis differ - a theory is a widely accepted idea that has serious evidence behind it, backing
from a theory or it up; ex: theory of evolution
prediction? - a hypothesis is a proposed explanation for observed phenomena
- a hypothesis must generate testable predictions
- theories are generally broader than hypotheses
14. null hypothesis - a hypothesis that states a lack of relationship between 2 factors
- easy to disprove
ex: Echinacea has NO effect on the likelihood of catching the common cold or the
duration of the symptoms of a cold
15. is it possible to no it's impossible
prove a hypoth-
esis is absolutely
and permanently
true?
16. 3. What does it - make sure there are no underlying differenced between the experimental
mean to control groups
an experiment? - change only ONE variable at a time
- treat all subject the same except for the one deviation which would not get the
treatment and be the control group
17. treatments an experimental condition applied to research subjects
LS15 MIDTERM - UCLA Phelan
AND WELL DETAILED ANSWERS) LATEST UPDATE 2025/2026
Study online at https://quizlet.com/_5hvxy8
1. 1. Scientific think-
ing, what is it for?
and be able to
use it
2. scientific think- - empirical (based on observations and experiences not solely logic)
ing - self correcting
- observation
- hypotheses
- predictions
- experiments
- conclusions (modify hypotheses, and continue the process)
3. scientific method - organized
- empirical
- methodical
- structured way of finding information about observable events in nature
- lets us reject hypotheses about how the world works
4. steps of the sci- 1. make observations
entific method 2. formulate hypotheses - is it testable? refutable?
3. make a prediction
4. conduct an experiment - control all variables BUT one, randomized, double
blind
5. analyze results, draw a conclusion (if evidence disproves hypothesis, construct
a new hypothesis)
6. report results
5. is the scientific yes! it doesn't have to be step by step
method flexible?
6. put a hypothesis to the test, the results can decisively determine whether a
hypothesis is correct
, LS15 MIDTERM - UCLA Phelan
Study online at https://quizlet.com/_5hvxy8
what does a "crit-
ical experiment"
do
7. class examples of - does it rain more on weekends?
scientific method - real vs artificial vanilla
- "maze bright" vs "maze dull" rats
8. class example: - find average Monday and Saturday rainfall; rains 22% more on Saturdays
does it rain more - hypothesis: particular matter from car exhaust builds up during the week leading
on weekends? to cloud formation and then rain on the weekends
- experiment: collect data from somewhere with no cars (ocean)
- results: there is equal rainfall on each day in the ocean, PROVING that car exhaust
affects the trend of more rain on weekends
9. class example: - Phelan baked batches of cookies with real vanilla and with artificial vanilla
real vs artificial - asked wife which one tasted better
vanilla in choco- - concluded that there was no difference in taste between the types of vanilla used
late chip cookies
10. class example: - have "maze dull" and "maze bright" mice
is maze running - with each generation, test all mice for maze learning ability and breed only the
genetic in mice? top 20% and bottom 20%
- observe new generations
- conclusion: over time, the extremes got more and more exaggerated
- maze running is not genetic but the allele for fear is in mice; less fear = solve
maze quicker, more fear = solve maze slower
11. how to in- - randomize subjects
crease experi- - control your study
ment's power - use a double-blind design
R.C.D. - rat's cause diseases
, LS15 MIDTERM - UCLA Phelan
Study online at https://quizlet.com/_5hvxy8
12. what is it's a poorer model of the situation of interest
the cost-bene-
fit analysis of
having a more
controlled exper-
iment?
13. 2. How does a - a prediction only offers a guess of what will happen in the future
hypothesis differ - a theory is a widely accepted idea that has serious evidence behind it, backing
from a theory or it up; ex: theory of evolution
prediction? - a hypothesis is a proposed explanation for observed phenomena
- a hypothesis must generate testable predictions
- theories are generally broader than hypotheses
14. null hypothesis - a hypothesis that states a lack of relationship between 2 factors
- easy to disprove
ex: Echinacea has NO effect on the likelihood of catching the common cold or the
duration of the symptoms of a cold
15. is it possible to no it's impossible
prove a hypoth-
esis is absolutely
and permanently
true?
16. 3. What does it - make sure there are no underlying differenced between the experimental
mean to control groups
an experiment? - change only ONE variable at a time
- treat all subject the same except for the one deviation which would not get the
treatment and be the control group
17. treatments an experimental condition applied to research subjects
